M-250

Rev. G
P.D. Oscillating Piston Flowmeters:
2″ Type 4-MT and MTSC Petroleum
2″ Type 4D-MT LP Gas

Operating and Maintenance Manual for

Petroleum and LPG Truck Meters
2″ Type 4D-MT for LP-Gas 2″ Type 4-MT and MTSC for Refined Fuels
 WARNING!!
To ensure compliance with
U.L. Listing, use only
Genuine Neptune®
Replacement Parts.
 TABLE OF CONTENTS

DESCRIPTION PAGE
I. General Information .........................................................................................1

II. Installation ........................................................................................................2

A. LP-Gas Installation—Type 4D-MT.................................................................2
B. Petroleum Installation—Type 4-MT and Type 4-MTSC.................................4

III. Operation ..........................................................................................................7

A. LP-Gas Operation.........................................................................................7
B. Petroleum Operation.....................................................................................7

IV. Calibration and Adjustment ............................................................................8

A. 800 Series Register.......................................................................................8
B. Calibration (LP-Gas)......................................................................................9
C. Calibration (Petroleum)................................................................................11

V.Maintenance ...................................................................................................16
A. Meter Maintenance (General)......................................................................16
B. Register Maintenance (General)..................................................................18
C. Measuring Chamber Maintenance (General)..............................................19
D. Gear Train Maintenance (General)...............................................................21
E. Temperature Compensator Maintenance....................................................22
F. Petroleum Meter Maintenance....................................................................23
1. Double Trip Valve....................................................................................23
2. Operating Shaft Maintenance................................................................24
3. Air Release Maintenance........................................................................24
G. LP-Gas Meter Maintenance........................................................................25
1. Differential Valve Maintenance...............................................................25
H. Diaphragm...................................................................................................26

VI. Troubleshooting ..............................................................................................27

A. LP-Gas Meters............................................................................................27
B. Petroleum Meters........................................................................................27

VII. Appendices.....................................................................................................29
A. Bolt Torque Requirements...........................................................................29
B. Anti Seize Compounds...............................................................................29
C. 2” Type 4D-MT Dimensional Information....................................................30
D. 2” Type 4-MT Dimensional Information.......................................................31
E. 2” Type 4-MTSC Dimensional Information..................................................32
F. Meter Mounting Template...........................................................................33
G. 2” Type 4-MT No Differential Valve Dimensional Information......................35
 2″ LP-GAS (TYPE 4D-MT) AND PETROLEUM (TYPE 4-MT, MTSC) TRUCK FLOWMETERS

SECTION I — GENERAL INFORMATION

NOTE: This manual covers the installation, calibration and mainte- GENERAL INFORMATION
nance procedures for the 2 ″ 4D-MT LPG Flowmeter and the 2 ″ Type 4-MT
and MTSC Petroleum Flowmeter (See cover photograph of meters).

The instructions are, for the most part, applicable to both the 2 ″ Type
4-MT and MTSC Petroleum and the 2 ″ Type 4D-MT LP-Gas meters. How-
ever there are some procedures and routines specific to each meter; in
these cases, individual sections will be devoted to each meter.

The 2″ Type 4D-MT and Type 4-MT, MTSC meters are very similar in
construction and share many of the same parts. Common to both meters are
the main case and measuring chamber, the body of the air/vapor release, and
the register/gear train and optional temperature compensation assembly. The
LPG version uses a differential control valve at the outlet to maintain backpres-
sure on the meter, which ensures that vapor is not measured. The Petroleum
version uses a shutoff or optional preset valve (connected to the register) and
incorporates an extension on the top of the air release for better elimination
of entrained air and measurement of heavy oils.

Both units include a stainless steel strainer, housed in the air/vapor release,
which is a fine mesh filter in a double sleeve.

A Temperature Compensator is used in most LPG meters and some

petroleum meters. The way in which it operates is the same for both units.
By sensing product temperature, the Temperature Compensator controls the LP-GAS METER
readout drive ratio to provide a registration compensated to 60°F. The Tem-
perature Compensator is located in a housing between the top of the meter
maincase and the bottom of the register and adds approximately seven (7)
inches to the overall meter height.

The following components are unique to the 2″ Type 4D-MT LPG Meter:

— The Vapor Release Assembly, which prevents entrapped vapor from

passing through the flowmeter, has a hydraulic-assisted main valve with a float-
operated pilot valve. When vapor collects in the Vapor Release, the vent valve
opens venting vapor to the supply tank establishing pump pressure to close
the Differential Valve. A hydrostatic pressure relief valve is incorporated into the
cover to protect the meter from excessive pressure and possible rupture. This
valve provides controlled venting of product vapor through the vapor return
line back to the storage tank to relieve pressure inside the meter.

— The Differential Valve is diaphragm-actuated and opens when at least

15-psi pump pressure is established at the inlet of the flowmeter. This valve
serves three functions to assure system measurement accuracy by requiring:
(1) pump operation for delivery, (2) adequate back pressure to prevent prod-
uct vaporation during measurement, and (3) blockage of flow when the Vapor
Release valve opens.

Page 1
 SECTION II — INSTALLATION
A. LP-GAS INSTALLATION — TYPE 4D-MT
CAUTION LP-GAS METER
Always install the flowmeter according to local Safety Codes for LPGas INSTALLATION
equipment. The flowmeter shall be installed outdoors, away from build-
ings and sources of ignition. External examination is recommended every
2 years and a pressure test at the maximum working pressure (24 bar)
every 10 years. LPGas meters should be adequately grounded to eliminate
hazard due to static electrical discharge.

1. Installation Planning. Plan the installation for maximum rate of delivery, sizing
the supply tank outlet, piping and valve for free gravity flow to the pump suction.
To accomplish this, locate the pump as close as possible to the supply tank and
use short inlet connections with few restrictions. Keep the number of elbows to a
minimum, and use large radius elbows, wherever possible. To reduce the likelihood
of causing vapor in the pump suction line, install a pump bypass valve in a return
line to the supply tank as shown in the installation drawing. (See Figure 2).

2. Flowmeter Location. Locate the flowmeter at any convenient place in the pump
discharge line. If the flowmeter is to be operated under extremes of environment (dirt,
water, physical damage, etc.) an enclosure or other protection should be provided.
Allow sufficient clearances for removal of the register, strainer and vapor release. Do
not install any bypass around the flowmeter; the valve in such a line might eventually
leak, work open, or be left open causing improper measurement.

3. Configuration. The meter and vapor release assembly may be rotated 90

degrees for better fit on board the truck. To conform with Weights and Measures
requirements, install flowmeter (right- or left-hand assembly) so that flowmeter
nameplate is visible. BOLT TORQUES AND
ANTI-SEIZE COMPOUNDS
4. Cleaning. All piping on the inlet side of the flowmeter should be very thor-
oughly cleaned out. Flush out all lines thoroughly before installing the flowmeter.
While the installation is still new, the strainer should be cleaned very frequently. COMPANION FLANGES
After the system has been thoroughly flushed of foreign material, only periodic
cleaning is required. IMPORTANT: Refer to Page 17 for maintenance interval
requirements.

5. Piping and Bolting Considerations. The meter is supplied with a ductile iron
inlet check valve tapped for 2″ NPT and a ductile iron companion flange tapped for
2″ NPT on the outlet. Secure the connecting piping to prevent strain on the flow-
meter. Use pipe compound sparingly or suitable pipe tapes on male threads only.
IMPORTANT: Refer to the chart on page 28 for bolt torques and anti-seize
compound information.

FIGURE 1 2″ Type 4D-MT (Cutaway View)

with Automatic Temperature Compensator

Page 2
 6. Vapor Release. Provide the installation with means for pressure relief as VENT LINE LP-GAS
outlined the National Fire Protection Association Pamphlet 58. The vent line
from the flowmeter’s vapor vent to the vapor space of the supply tank
should be 3⁄8-inch OD tubing or equivalent pipe size. The vent line check
valve functions as a shut-off valve when disconnected and permits removal of
the strainer for cleaning or when other service is performed on the flowmeter.
The Vapor Release vent line must be returned to the vapor space of the supply
tank and normally should not be made a common connection with other vapor
lines or pump bypass lines. When properly installed, this line must permit free
flow in either direction. If the valve in the vent line is closed, the flowmeter will
not function. Also, if the valve in the vent line is closed, the hydrostatic relief
valve in vapor release cannot relieve pressure inside meter. Therefore, an ad-
ditional hydrostatic relief valve must be installed in the vent line between the
meter and the valve. These instructions must be followed in order to maintain
proper function of the differential valve.
NOTE: A vapor equalizing line should not be used from supply tank to tank
being filled as such connection would cause confusion as to the amount de-
livered as a result of possible passage of vapor in either direction.
1. Register
2. Check Valve
3. Pressure Bypass and Vent Valve
4. Vapor Release and Strainer
5. Inlet Check Valve (at rear)
6. Thermometer Well
(uncompensated flowmeter)
7. Strainer Cover
8. Manual Valve
9. External Pump Bypass Valve
10. Pump
11. Internal Control Valve
12. Flowmeter
13. Differential Valve
14. Thermometer Well
15. Temperature Compensator
FIGURE 2
7. Startup Procedures INSTALLATION ARRANGEMENT LP-GAS
• Pressurize the system slowly by allowing vapor flow through the vent line. STARTUP PROCEDURE
Check for system leaks. Then pass sufficient liquid through the system to clear
the lines of air and vapor.
• After starting pump, slowly open outlet valve downstream of the flowmeter.
Check the rate of flow after the system is filled; it should not exceed rated
maximum flow of flowmeter.
• Adjust the external pump bypass to deliver the maximum practical rate of
flow for the least amount of pump pressure.
• NOTE: The pump relief valve (normally built into the pump assembly) should
relieve at a pressure above which the external bypass has been set.
• Maximum working pressure on the system must not exceed 350 psi.
Avoid the use of a small diameter hose or pipe and resultant need for exces-
sive pressures to achieve the desired flow rates; these may result in leakage,
undue wear on pump and unsafe operation.
• All flowmeters are carefully calibrated and tested at the factory and no
changes should be necessary.
• While the installation is still new, clean the strainer frequently. After
the system has been in service, only periodic cleaning is necessary. DO NOT
OPERATE THE METER WITHOUT THE STRAINER!

Page 3
B. PETROLEUM INSTALLATION — TYPE 4-MT And TYPE 4-MTSC

CAUTION
Containers employed to collect vapor or liquid discharged from the
meter vapor release should be of sufficient size to prevent any liquid es-
cape during normal operation, and should have a suitable flame arrestor
vent. All vent lines and fittings should be of metal construction, and all
valves should be designed so that normal vibration does not cause ac-
cidental opening.

1. Installation Planning. For Pumped Systems, plan the installation for maxi- PETROLEUM METER
mum rate of delivery, sizing the supply tank outlet, piping and valve for free ­INSTALLATION
gravity flow to the pump suction. To accomplish this, locate the pump as close
as possible to the supply tank and use short inlet connections with few restric-
tions. Keep the number of elbows to a minimum, and use large radius or sweep
elbows wherever possible.

On Gravity Systems, piping should be pitched uniformly down from the

compartment to the flowmeter to prevent the accumulation of air at high points.
The point to which the discharge line from the flowmeter will drain should be
at least 6″ above the center of the flowmeter spuds but below the bottom of
the compartments.

2. Flowmeter Location. The flowmeter may be located at any convenient

point on the discharge line from the pump. The piping on the outlet side of the
flowmeter should be so arranged as to eliminate the possibility of draining the
measuring chamber. All piping connected to the flowmeter must be firmly se-
cured to prevent strain on the flowmeter casing. The use of flexible connections
to the pump or tank is recommended. Mount the unit securely to the chassis
of the truck to prevent strains due to vibration. It is also advisable to enclose
the flowmeter if possible to protect it from damage.

Be sure to allow headroom for the removal of the strainer basket, register,
and air release mechanism. There must be no by-pass connection around the
flowmeter. Experience has shown that the valve in this line will eventually leak,
work open or be accidentally left open.

The meter and air release assembly may be rotated 90 degrees for better
fit on board the truck. To conform with Weights and Measures requirements,
install flowmeter (right- or left-hand assembly) so that flowmeter nameplate is
visible. Instructions on changing the assembly from right hand to left hand and
left hand to right hand are covered on Page 12 of this manual.

3. Piping Considerations. The meter is supplied with a 2″ NPT threaded BOLT TORQUES AND
ductile iron companion flange on the inlet and a 2″ 150 lb. flat face ANSI Type ­COMPANION FLANGES
flange on the outlet. Use pipe thread cement on the male threads only. IM-
PORTANT: Refer to the information on Page 28 for bolt torques and anti-seize
compound recommendations.

4. Blowing the Hose. As it is impossible to blow all the liquid from the hose, the
amount of liquid left in the lines on the discharge side of the flowmeter will not
be the same before and after every delivery. It is therefore recommended that
provision be made to keep the hose and outlet piping full of liquid at all times.
For this purpose a hose nozzle with a check valve should be used.

Page 4
 FIGURE 3
TRUCK INSTALLATION —PETROLEUM

5. Pumping Out Underground Tanks. In making provisions for pumping out

underground tanks, DO NOT provide any connection between the outlet of
the flowmeter and the compartments or manifold. A valve in this line which is
leaky or carelessly left open will allow part of the metered liquid to be diverted.

6. Vent Pipe. The vent pipe from the air release should be 1″ pipe or equivalent.
Care should be taken to prevent any possible obstruction to the free flow of
air through this line. Do not exceed torque recommendation for vent pipe or
vapor release cover may be damaged.

— On Pump Systems it should either be connected to the top of one of the

compartments or run into a container of about 5 gallons capacity to collect
any liquid discharged with the air.

— On Gravity Systems it should be connected to the outlet side of the flow-

meter, running the line as high as possible to prevent any slight leakage of the
valve from bypassing the flowmeter.

— On Combination Pump and Gravity Systems, run the vent lines as for
pump operation and install a check valve as close as possible to the air vent
connection to prevent the possibility of drawing in air at this point. In addition
a second line should be connected from the air release to the discharge side
of the flowmeter with a check valve installed to prevent flow of liquid back
through vent line during pump operation.

If the valve of an empty compartment or auxiliary suction connection is

open even slightly, while another compartment is being emptied, air drawn in
through, this valve will be churned up with the liquid to such an extent by the
pump that it may be carried through the air release and cause over-registration.
The volume of the air release of the Type 4-MT AND MTSC has been greatly
increased so that this is less of a problem than with earlier designs; however
careful planning of the installation combined with this new feature will eliminate
this over-registration situation.

Page 5
 INTERLOCKING OF
COMPARTMENT
OR MANIFOLD VALVES

FIGURE 4
MANIFOLD VALVE INTERLOCKING

7. Valves and Interlocks. Either the compartment or the manifold valves should
be interlocked so that delivery can be made from only one compartment at
a time. Compartment valves are ordinarily interlocked by means of a selector
lever in the can box.
Manifold valves may be of the 2 way-3 port lubricated pug type so arranged
as to achieve the same purpose. (See illustration).
On Gravity or Pump and Gravity Systems, the back pressure valve in the
bottom of the air release unit must be removed (see Page 24).

8. Installation and Startup Procedures

— Inlets and outlets are clearly marked; do not install backwards. INSTALLATION AND
— All piping on the inlet side of the flowmeter should be very thoroughly cleaned STARTUP PROCEDURES
out. Flush out all lines thoroughly before installing the flowmeter. PETROLEUM
— Pass sufficient liquid through to clear the line of air.
— Check the rate of flow. It should not exceed the maximum rate of flow for
the meter.
— The by-pass on the pump should be so regulated as to deliver the maximum
practical rate of flow for the least amount of static pressure. Pressure on the
flowmeter should not exceed 150 psi. Do not try to increase the rate of flow
through undersized pipes and fittings by means of excessive pressures which
will cause leaking gaskets and collapsed air release floats.
— Temperature of the liquid should not exceed 140°F.
— Test the flowmeter in a prover of not less than 100 gallons. All flowmeters
are carefully calibrated and tested at the factory and no changes should be
necessary.
— If the registration is inaccurate, refer to section on calibration.

Page 6
 SECTION III — OPERATION

A. LP-GAS OPERATION LP-GAS FLOWMETER

OPERATION
1. If it has not been done so already, pressurize the system slowly by allowing
vapor flow through the vent line. Then pass sufficient liquid through the system
to clear the lines of air and vapor.

2. Reset the 800 series register to zero by turning operating knob to the rear
stop. On Printer models, first insert ticket. To insert a ticket, be sure that the
reset knob is turned forward to a stop. Then depress the dust bar above the
ticket and insert ticket either “face down, bottom end first” or “face up, top
end first” as noted on the instruction plate. Turn reset knob backward to stop.
This resets the visible wheels to zero, locks ticket in place, and prints the initial
reading on the ticket. The ticket now cannot be removed without tearing it.

3. Start the Pump. Slowly open the outlet valve downstream of the flowmeter.

4. Open hose valve and make delivery.

5. After completion of delivery on Printer models, stamp final reading on ticket

by turning reset knob forward to the front stop. This prints the final reading and
releases the ticket. The cumulative totalizer is visible through the mask at the
upper right-hand corner of register; this total may be manually written on the
ticket or in a log if desired.
TOTALIZER
DUST BAR DUST BAR OPERATING KNOB

RESET KNOB
800 SERIES REGISTER
DIAGRAMS

CLAMP EMERGENCY
SCREW PRESET BUTTONS STOP BUTTON
TRIP ADJUSTING TRIP ADJUSTING
SCREW COVER SCREW COVER

FIGURE 5 FIGURE 6
STANDARD 800 SERIES PRESET 800 SERIES
PRINTER REGISTER PRINTER REGISTER
(PETROLEUM ONLY)
B. PETROLEUM OPERATION

1. Reset the 800 series register to zero by turning operating knob to the rear
stop. On Printer models, first insert ticket. To insert a ticket be sure that the
operating knob is turned forward to a stop. Then depress the dust bar above
the ticket slot and insert the ticket either “face down bottom end first” for
“face up top end first” as noted on the instruction plate. Turn the operating
knob backward to the stop. This resets the visible wheels to zero, locks the
ticket in place and prints the initial reading on the ticket. It is now impossible
to remove the ticket without tearing it.

Page 7
2. On Preset models, set the Preset wheels to the desired quantity using the
push buttons on the lower face of the register. Pushing the red emergency stop
button will trip the valve. After it has been used the mechanism may be set for
a new Figure or the delivery may be completed automatically as originally set
by re-opening the valve except if the flow has been stopped with 8 gallons or
less remaining. In this case the delivery can be completed by manually holding
the valve partially open.

3. Start pump and open the valve (manual or preset).

4. Open hose nozzle and make delivery. When the preset volume is reached,
the valve will close on Preset models.

5. After completion of delivery on Printer models, stamp final reading on ticket

by turning operating knob forward to the front stop. This operation prints the
final reading and releases the ticket.

SECTION IV — CALIBRATION AND ADJUSTMENT

A. 800 SERIES REGISTER ADJUSTMENT

800 Series printer registers are shipped from factory with the ticket guides
properly adjusted. If it is necessary to reposition ticket, proceed as follows:

1. Remove register top cover. ADJUSTING TICKET

POSITION
2. Insert a ticket into the printer. Loosen the clamp screws on the rear of the
ticket guides. Move the guides to the right or left as required. Tighten clamp
screw. The ticket must slide freely between the guides. If the ticket binds at the
forward end of the guide, remove the guide, and rebend the tail of the guide.
3. To raise or lower printing, push the two stop pins to the front or rear with
end of a screwdriver.
4. Replace the top cover and reseal. STOP PINS

To change the letters that are printed ADJUSTING PRINT

on the ticket, follow this procedure to LETTERS
change the position of the letter wheels.

1. With top cover removed, the “letter”

wheels are visible.
2. Using a screwdriver or similar tool, turn
wheels until desired letters are in position
to print. The letters appearing at top are
in position to print.

CLAMP SCREWS LETTER WHEELS

FIGURE 7
PRINT UNIT ADJUSTMENTS

Page 8
B. CALIBRATION (LP-GAS)

Test the flowmeter using a volumetric prover large enough to permit the
flowmeter to operate for at least one minute at maximum flow rate. Slip tube
and rotary gauge readings are not sufficiently accurate for proving flowmeters.
A detailed description of LP-Gas test procedure may be found in the NCWM
Course 305, “Liquefied Petroleum Gas Liquid Measuring Devices.” Specifica-
tions and tolerances are contained in NIST Handbook H-44.

A thermometer well is provided for taking temperature readings while

calibrating. It is located in the compensator on compensated flowmeters. On
uncompensated flowmeters, it will be found in the strainer cover. It is covered
by a snap plug to keep dirt from entering the well. The well should be filled with
permanent type anti-freeze, if available, or with a light oil when temperature
readings are to be obtained.

If a gravimetric test is used, the conversion to gallons must be on the basis

of: (1) specific gravity determined at the time of test (not an assumed value),
at (2) the temperature of the product as it passed through the flowmeter.

Slip tube and rotary gauge readings are not sufficiently accurate for use
as flowmeter checks and will produce erratic results.

Erratic Registration
Erratic registration may be an indication of vapor or dirt in the measur- Erratic Registration
ing chamber. It cannot be corrected by recalibration. Clean the strainer and if
necessary the flowmeter as directed under MAINTENANCE. For proper opera-
tion the installation must be in accordance with the descriptions in Section II
of this manual.

Consistent Over or Under Registration

When the flowmeter registers consistently either more or less than is Consistent Over or
delivered, the calibration may be corrected in the following manner: Under Registration

Procedure for Uncompensated Flowmeters

Uncompensated Flowmeters
Test the flowmeter to determine any error in registration. If there is an error
Error <0.309%
less than 0.309%, proceed as follows:
1. Remove the register top cover.
2. Lift and turn change gear shifter (see Figure 8) in the direction indicated on
the top of the shifter.
3. There is a series of holes in the plate into which the guide pin enters at
different settings. Altering the setting by one hole changes the calibration ap-
proximately 34 cubic inches in 100 gallons, or .15%.

Example: Suppose that the flowmeter consistently gives 68 cubic inches

too much when it registers 100 gallons. After removing the cover plate move
the gear shifter 2 spaces to the right (from position E to position C) to decrease
the delivery about 68 cubic inches in 100 gallons.

Page 9
 After changing the calibration always replace the top cover, making sure Uncompensated Flowmeter
that the sheet steel housing on the sides and back fits into the groove in the Error >0.309%
bottom edge of cover. Run a small amount of liquid through the flowmeter
before testing. In order to prevent tampering, always reseal after calibration is
completed. If there is an error greater than 0.309% (approx. 68 cu. in. in 100
gals.), proceed as follows:

1. Remove the register. (Refer to REGISTER MAINTENANCE.)

2. Looking into the bottom of the register determine the number of teeth on
the “R” and “S” change gears. (See Figure 9).
3. Refer to CHANGE GEAR CHART (Figure 10) and select the proper gears.
4. Install new gears being sure to put change gear “R” on the “R” spindle and
change gear “S” on the proper spindle.
5. Replace register and tighten two screws.

Procedure for Compensated Flowmeters Compensated Flowmeters

1. Remove the two seal screws and cover from the temperature compensator.
(See Figure 11). Do not remove sealing wax at top of lever arm.
2. Move anchor pin from “Compensated Anchor” to “Uncompensated Anchor.”
(Flowmeter readings will now be uncompensated.) (See Figure 11).
3. Perform same LP-Gas flowmeter test procedure as outlined for uncompen-
sated flowmeters.
4. If necessary to change flowmeter calibration, refer to PROCEDURE FOR
UNCOMPENSATED FLOWMETERS, steps 1 to 5.
5. Move anchor pin to “compensated Anchor” and operate flowmeter for at
least 50 gallons before proceeding with calibration tests. (Flowmeter readings
will now be temperature compensated.)
6. Perform same flowmeter test procedure used for uncompensated flowme-
ter. Temperature readings must be taken at the prover only. (Temperature at
flowmeter is assumed to be 60°F.)
7. If necessary to adjust compensated registration, turn calibration dial located
at the lower end of the Lever Arm (to turn adjustment, use wrench on hex hub
of dial.) Turn clockwise “To Give More” or counterclockwise “To Give Less.”
Each dial graduation will change compensated delivery approximately 0.15%;
that is, 34 cubic inches per 100 gallons.

“REV.” SPINDLE
FOR CHANGE GEAR “S”
STOP PINS

CHANGE GEAR “R” CHANGE GEAR “S”

(ON “STD” SPINDLE)

FIGURE 8 FIGURE 9
GEAR SHIFTER CHANGE GEAR
ADJUSTMENTS ARRANGEMENT

Page 10
 UNCOMPENSATED
ANCHOR

ANCHOR
PIN
COMPENSATED
DIAL
CALIBRATION THERMOMETER
DIAL WELL

FIGURE 10 FIGURE 11
REGISTER “CHANGE GEARS” FOR REMOVING ANCHOR PIN
2″ FLOWMETERS (US GALLONS) FOR CALIBRATION

C. CALIBRATION (PETROLEUM) PETROLEUM CALIBRATION

NOTE: For temperature corrected petroleum meters you may follow

procedure for calibrating LP-Gas meters (see Page 10).

1. Test all flowmeters with 100-gallon or larger test measures. Do not base
calibration upon truck compartments.

2. Preset flowmeters should first be tested and adjusted without the Preset
(set the register for more than the test quantity), then tested with the Preset.

3. If the Preset mechanism does not trip correctly, see instructions on Page
14 “To Adjust the Tripping Point.” Rerun the test, and then if the delivery is not
correct, a service man should be called.

Erratic Registration Erratic Registration

Erratic registration is an indication of trouble in the system, commonly
caused by air or dirt in the measuring chamber. Do not try to correct this by
recalibration of the flowmeter immediately; first check over the piping for air
leaks, clean the strainer and then, if the trouble has not been found, clean the
flowmeter as directed on pages 16, 17, 18 and 19. If this does not correct the
trouble, check for faulty installation.

Over-registration is an indication of air; under-registration is generally

caused by dirt or pipe scale in the measuring chamber or the liquid by-passing
the flowmeter in some manner.

Page 11
 When the flowmeter registers consistently either more or less than is de-
livered, the calibration may be corrected in the following manner:

1. Remove four screws holding top cover and remove cover.

2. Lift and turn the gear shifter (see Figure 8 on Page 10) in the direction indi-
cated on the top of the shifter.
3. There is a series of holes in the plate into which the guide pin enters at
different settings. Altering the setting by one hold changes the calibration ap-
proximately 34 cubic inches in 100 gallons.
After changing the calibration always replace top cover, making sure that
the sheet steel housing on the sides and back fits into the groove in the bot-
tom edge of cover. Run a small amount of liquid through the flowmeter before
testing. To prevent tampering, always reseal after calibration is completed.

Changing Meter from Left Hand to Right Hand Assembly CHANGING CONFIGURATION
When the flowmeter is assembled as a Left Hand assembly and it is desired OF THE METER
to change it to a Right Hand assembly, or vice versa, proceed as follows: (Right hand to left hand
1. Remove clevis pin (E) from valve linkage. and vice versa)
2. Unscrew the outside register link lock nut (P) and remove connecting rod
(G) and clevis (F) as a unit.
3. Remove register link (N), rotate 1/2 turn and reassemble onto register as
described in appropriate valve adjustment instructions.
4. Loosen two clamp screws on lower front of register, lift register up and turn
register 180 degrees.
5. Remove operating shaft cap screw (C) on both sides.
6. Interchange connecting rod arm (H) and valve operating handle (A). The
connecting rod arm must be assembled with notches (J and K) in specific
relationship. (See item 3 of valve linkage adjustment instructions for details
regarding position of notches).
7. Reassemble operating shaft cap screws (C).
8. Remove valve handle stop set screws (B) and screw into hold on opposite
side of valve.
9. If the inlet is moved to opposite side, be sure to rotate the air release cover
assembly 180°.

FIGURE 12
RIGHT HAND PRESET VALVE ASSEMBLY

Page 12
 FIGURE 13
LEFT-HAND ASSEMBLY

After completing the above instructions, the valve linkage must be adjusted
in accordance with the following procedure ADJUSTMENT OF PRESET VALVE. PRESET VALVE ADJUSTMENT
To adjust valve linkage
ADJUSTMENT OF PRESET VALVE (PETROLEUM ONLY)
Note: Before any adjustment of the Preset Valve is made, be sure that
the Preset setting wheels indicate a quantity, other than zero, to insure that
the trip mechanism of the register is in proper position.
1. Depress the emergency stop button on the register and turn the shaft (O)
clockwise.
2. Assemble register arm (N) on knurled knot in position as shown for specific
assembly. (See illustration). Arm should move an equal distance each side of
vertical center line (M) (Angle x=x).
3. Assemble valve arm (H) as shown for specific assembly. On the right hand
assembly there must be one notch between the cast mark (K) on the valve arm
and the cast mark (J) on the stop plate (J above K). On the left hand assembly
these cast marks must be in line.
4. Assemble one nut (P) on connecting rod (G) and assemble clevis to the
other end of the connecting rod a distance of 1″.
5. Insert end of connecting rod through the register arm link and assemble
clevis (F) to valve arm (H) using upper hold (Figure 13). Insert clevis pin (E).
6. Open valve all the way. The opening of the valve is stopped by the set screw
(B) which should project approximately 1/8” below the lug holding it. Turn shaft
(O) clounterclockwise to latch mechanism. With valve held open, tighten nut
(P) against register arm link. The assemble and tighten second nut at (P).
7. Depress the emergency stop button and allow the valve to close. At this
point the linkage between the valve and the register must be free. If it is not,
the above adjustments must be rechecked.
8. Set the register to deliver the minimum quantity and open valve to run
product through the flowmeter.
9. After the initial trip occurs the valve should close to the intermediate flow
position. This rate should be approximately 20 to 25 gpm. If the valve closes
too far, or all the way, unscrew clevis (F) on rod (G) to hold valve open further. If
the rate of flow is too fast during the intermediate position, turn the clevis onto
the rod to allow the valve to close further. It should not be necessary to turn more

Page 13
than one turn in either direction.
10. It is sometimes necessary to change the position of set screw (B) if the clevis
has been readjusted. If the register mechanism will not latch up, unscrew the
set screw to allow the valve to open further. If the connecting rod (G) is under
compression, when the valve is held all the way open, turn the set screw down
to relieve the pressure on the register.
11. The preset trip adjusting screw should be near its mid-position. If a small
adjustment of this screw will not permit the register to shut off “on the mark” it
is usually possible to correct this by a slight adjustment of the clevis (F). This
will move the main valve nearer to or further away from its seat during the in-
termediate flow and thereby change the amount of time needed for the valve
to fully close at the last trip. (Also see “To Adjust the Tripping Point”)

Note: If it is difficult to obtain proper rate of flow during intermediate trip posi-
tion and still have register latch up fully, check Preset valve to insure that it is
opening all the way. Check valve by removing set screw (B) and clevis (F) from
valve arm; open valve as far as possible. The distance between lug on arm and
on stop plate must not be more than 1⁄4″.

To Adjust the Tripping Point

Registers are shipped from the factory with the Preset mechanism adjusted
to trip correctly at the normal rate of flow.

If a change in the valve closing speed of closing or some other reason

causes the Preset not to trip at the correct point, the trip point may be adjusted
as follows:

If the valve is closing “off the mark,” either late (over delivery) or early (under
delivery), adjust the clevis (see illustrations, “E” on Pages 12 and 13) in half-turn
increments to bring the trip point to the zero mark. Turn the clevis to lengthen
the connecting rod when the trip point is early, or turn to shorten the rod when
the trip point is late. Continue this procedure until the final trip is on or close to
the zero mark. The set screw (B) must also be readjusted as described in “To
Adjust Valve Linkage.” The intermediate flow rate will be satisfactory when the
final trip is adjusted as described.
DUST BAR OPERATING KNOB
Further adjustment of the trip point
is possible, but is not recommended
for normal applications. The following
procedure should be used only when
very exact setting of the final trip is
necessary.
Adjust the clevis, as described
above, and proceed as follows:
Remove the trip adjusting screw
cover located in the lower right corner CLAMP
of the register front housing (see il- SCREW PRESET BUTTONS EMERGENCY
STOP BUTTON
lustration). Insert a narrow blade (3⁄16″) TRIP ADJUSTING
SCREW COVER
screwdriver until it engages the slotted
FIGURE 14
head of the adjusting screw. One turn of
800 SERIES REGISTER
this screw will change the tripping point
DIAGRAM

Page 14
about one-quarter of one-tenth gallon.
If the Preset trips before reaching the zero mark (early), turn the adjusting
screw clockwise.
If the Preset trips after reaching the zero mark (late), turn counterclock-
wise.
Do not turn the adjusting screw more than 11⁄2 turns. If the trip point is
not on zero after 11⁄2 turns, return the adjusting screw to its original position
and turn the clevis a half turn in the appropriate direction. Then repeat the trip
screw adjustment procedure.

Page 15
 SECTION V — MAINTENANCE

A. METER MAINTENANCE (General) GENERAL MAINTENANCE

For sustained accuracy of Actaris LP-Gas and Petroleum Flowmeters, little
maintenance is required other than to see that the proper conditions of operation
are preserved. Once the flowmeter has been installed correctly, these conditions
consist merely in guarding against foreign matter, such as vapor, air, sediment
or water entering the measuring chamber. However, should any malfunction
develop do not dismantle the flowmeter until the cause of the trouble has first
been determined. Refer to suggestions in “TROUBLESHOOTING.”

The liquid passing through the measuring chamber must be free of grit and SEDIMENT
other forms of sediment to prevent unnecessary friction and to eliminate scoring
of the piston and chamber walls. Evidence of trouble from this source will be
found in under registration of the flowmeter. Periodic cleaning and inspection
of the flowmeter strainer will help to insure maximum flow rate and to prevent
possible damage of the flowmeter if clogged strainer ruptures.

Being an instrument that measures by volume, a flowmeter will record VAPOR/AIR

the passage of vapor or air as well as the liquid being measured, resulting
in over-registration. In LP-Gas, this will not occur with proper Vapor Release
and Differential Valve function and installation. For petroleum products, over-
registration will be prevented through the proper use of the air release valve,
which vents air before it passes through the measuring chamber.

Incidental water will cause no damage to the flowmeter. Trouble from this WATER
source may be expected only when water is allowed to stand in and around
the flowmeter for a considerable period of time.

When washing trucks, care should be taken to cover the register. Water in
the register will cause trouble particularly in cold weather when ice may form
and cause sticking.

While the installation is still new, the strainer should be cleaned very fre- CLEANING
quently. After the system has been thoroughly flushed of foreign material, only
periodic cleaning is recommended.
Before a flowmeter is put in storage, the measuring chamber must be flushed STORAGE
with a light lubricating oil of the best quality to prevent injury from condensation.

CAUTION
Before opening any part of the flowmeter, close valve between sup-
ply tank and flowmeter. Disconnect coupling vent line at vapor release
cover. Perform the following outdoors, away from building or sources of
ignition:
Open valve slowly at end of delivery hose or other outlet piping. After
pressure is dissipated unscrew Vent Valve (hex. nut) slowly (maximum 3
turns) on top of Vapor Release to depressurize product in flowmeter.

NOTE: The main components of the 2 ″ Type 4-MT and 4D-MT meters
are made of cast aluminum. The bolts themselves are plated steel, and may
damage the aluminum meter components if overtorqued. To avoid problems
associated with overtorquing of the bolts, refer to Page 28 of this manual
for exact torque requirements and recommended anti-seize compounds.

Page 16
To Clean the Strainer
Remove the strainer cover and strainer. Clean strainer with compressed
air. Inspect strainer for any breaks or other defects and replace if necessary.
Reinstall strainer and strainer cover.

To Inspect Air/Vapor Release Unit.

Trouble with this unit may arise from: (1) Collapsed ball float allowing vent
to remain open; (2) dirty or worn valve disk; or (3) binds in float linkage.
1. Uncouple the vent connection (See Caution).
2. Remove the cap screws on the air/vapor release cover and lift out the
mechanism.
3. If the float is damaged, remove by taking out the hinge pins and replace
with a new one.

SLEEVE MAIN VALVE

FLOAT

MOUNTING COVER SCREWS

PISTON SEAL LOWER VALVE HOUSING

FIGURE 15
VAPOR/AIR RELEASE COMPONENTS

4. If the valve is leaky.

a. Remove the air/vapor release unit from the underside of the cover (by
unscrewing three small screws).
b.  Take off the sleeve (for petroleum, the sleeve with piston seal).
c. Move the ball in the direction of the valve housing as far as possible
and remove valve disc assembly.
d. The valve disc assembly should be taken apart to inspect for dirt or
defective pilot valve seat. Replace valve if seats are defective.
e. For Petroleum, replace piston seal, if defective.
f.  When reassembling, make sure that the valve disc assembly moves
freely in sleeve and for petroleum meters that piston seat is properly
positioned.

Faulty operation of this unit may be caused by defective valve seat or

torn diaphragm.

For more information on parts and components see form P250.

Adjustable Air Release

The current Type 4-MT and MTSC air release cover assembly includes a
fully adjustable float linkage for fine tuning the air release for various conditions.
The float can be raised or lowered to increase the sensitivity of the unit.

Page 17
 For those conditions where spitting is not an
issue, but improved air elimination is required, the
linkage can be shortened by removing the cotter pin
and adjusting the linkage in. Using gentle hand pres-
sure to lift the float to the top position, there should LINKAGE
5/16″
be a minimum of 5⁄16″ between the arms and the float (MIN.) REMOVE PIN
FOR ADJUST-
after adjustment. MENT

To reduce spitting, but also slightly reduce air 1/16″

(MIN.)
elimination, the linkage can be lengthened in a like
manner. Remove the cotter pin and adjust the link- DIRECTION OF FLOW

age out to lower the float. With the float in the down FIGURE 16.
position, the float should clear the inner wall of the air 2″ ADJUSTABLE
AIR RELEASE
release body by a minimum of 1⁄16″. When reinstalling
the cover assembly, be sure the float is oriented so
the incoming flow assists in raising the float. REGISTER MAINTENANCE

B. REGISTER MAINTENANCE
B. (GENERAL)
Register parts are such that
only minor field repairs are advis-
able. When a register is in need of
repair or service other than that for
which instruction is given here, it
CHANGE GEAR “R”
should be returned to the nearest CHANGE GEAR “S”
Actaris distributor. (ON “STD” SPINDLE)

FIGURE 17.
Register Removal 800 SERIES REGISTER — LOWER VIEW

Disconnect valve linkage at valve end (petroleum only — cotter pin, washer,
and clevis pin must be removed before hand). Loosen the two clamp screws
on lower front of register. Lift register off flowmeter.

When one register is removed and another substituted, (1) Check the number
of teeth on the change gears (see illustration). They must be the same as the gears
on the old register and on the same respective spindles. The number of teeth is
stamped on each gear. To remove these gears, close the split end of the spindle
slightly. (2) Make sure that the position of the change gear shifter is the same on
the new register as the old one. Each hole is lettered for convenience.
Cleaning Register Masks
Cleaning Register Masks

Register masks are made of plastic and require special treatment instruc-
tions for cleaning. If the mask becomes soiled with grease and oil, solvents for
these substances, such as kerosene or naphtha, may be used to remove dirt.
However, sprays that are commonly employed in cleaning glass windshields
must not be used as cleaners, since they may contain solvents.

A water solution of non-abrasive soap is recommended for washing grease,

oil, or dirt from the mask. It is then cleaned by rubbing gently with a soft cloth,
in a manner similar to cleaning window glass, rinsing the plastic in clean water,
and finally drying.

Page 18
 Scouring cleanser and similar material must not be used in cleaning the
mask, since they contain abrasives that scratch the surface.

The use of solvents, such as acetone, ethyl acetate, benzene, and eth-
ylene dichloride, to brighten the surface is never recommended since these
substances soften the surface of the plastic.

C. MEASURING CHAMBER MAINTENANCE (General) MEASURING CHAMBER

MAINTENANCE­
CAUTION
Before opening any part of the flowmeter, close valve between sup-
ply tank and flowmeter. Disconnect coupling in vent line at vapor release
cover. Disconnect coupling in vent line at vapor release cover. Perform
the following outdoors, away from buildings or source of ignition:
Open valve slowly at end of delivery hose or other outlet piping. After
pressure is dissipated, unscrew Vent Valve (hex. nut) slowly (maximum 3
turns) on top of Vapor release to depressurize product in flowmeter.

The Actaris 2″ Type 4-MT, MTSC and Type 4D-MT use the same measuring
chamber. In both new meters and replacement parts, each chamber contains
a matched piston and housing that have been calibrated together to achieve
the accuracy necessary for custody transfer. Pistons from one chamber may
NOT be placed into another chamber for use; the meter will not meet W&M
accuracy specifications.

The piston is covered with a special coating that increases the lubricity
and makes the surface more impervious to damage by contaminants. Because
it is hard, the coating is also brittle. Take care in the handling of the piston to
avoid chipping the coating.

To Remove and Disassemble Measuring Chamber

This operation is not difficult and may be performed by any competent Removal and Disassembly
mechanic. No special tools are required. No trouble need be expected. If these
few simple, but important, directions are followed. Do not open the flowmeter until
you have checked over all other possible causes of erratic registration.

1. Prepare a clean surface on which to place the parts as they are removed.
The parts are machined to close tolerances and should be handled with care.
Have a replacement gasket ready before opening the flowmeter.
2. Loosen the two clamp screws on the lower front of the register. Lift the
register off. On Preset models the valve linkage must first be disconnected.
(Remove cotter pin and washer at valve end.)
3. Remove the flowmeter cover taking care not to injure the gasket.
4. Lift the measuring chamber from the flowmeter casing.
5. Remove the upper cylinder head by removing the screws and then tapping
on the lugs protruding at the sides. Be careful not to scratch or nick any part
of the chamber.
6. Lift out the piston by its spindle. If care is taken to draw it straight, it should
come out easily. Do not force it.
7. Remove the control roller, seal pin, and diaphragm from the lower cylinder
head.

Page 19
To Clean the Measuring Chamber Measuring Chamber
The parts may be easily cleaned of scale, etc., by means of a good, coarse, Cleaning and Inspection
stiff bristle (not wire) brush and a petroleum solvent. All foreign matter, except
deeply embedded chips or heavy corrosion due to water, may be removed in
this manner. Do not use abrasives, such as emery cloth or sand paper. When the
piston is badly corroded, the whole chamber should be replaced.
The parts of the measuring chamber which may show wear after long
periods of service are the diaphragm and control roller. These parts will not
require replacement until the accuracy begins to fall off at low rates of flow. To
change these parts, merely substitute the new for the old, when the flowmeter
has been taken down for cleaning. Experience has shown that the sliding sur-
faces between the chamber and piston wear little if any.

SEAL
PISTON PIN DIAPHRAGM

ROLLER

SCREWS
UPPER CYLINDER HEAD
CYLINDER RING AND HEAD

FIGURE 18
MEASURING CHAMBER ASSEMBLY

FIGURE 19
CHECKING THE PISTON MOVEMENT

To Reassemble the Chamber in the Flowmeter To Reassemble the Chamber

Before reassembling the flowmeter, rinse all parts in a petroleum solvent. in the Flowmeter
If possible, flush out the flowmeter body. Assemble the parts carefully; they
should slide together easily without hammering or forcing. It is essential that
all contact surfaces between the upper and lower cylinder heads and the cyl-
inder, or between the measuring chamber and its seat in the casing, be clean
and free from nicks.
1. Assemble the diaphragm to the lower cylinder head.
2. Replace the seal pin. Place the control roller on its pin and see that it will
rotate freely.
3. Replace the piston and oscillate it carefully by hand; it should move easily
without binding. If it sticks, do not force it, but remove and locate the cause.
Do not file down the roller as this will impair the accuracy of the flowmeter.

Page 20
4. Replace the upper cylinder head and again oscillate the piston to make
sure that it is free.
5. When replacing the measuring chamber in the casing, be sure that the
seat is clean and free from nicks. Make sure that dowel pin in the main casing
enters the slot in the bottom cylinder head properly and allows the chamber
to rest on its seat.
6. Before replacing the cover, first be sure the chamber is properly seated and
inspect the gasket. Then set the arm of the gear train so that it will not come
down on the piston spindle.
7. Make sure that the cover is down on its seat before tightening the bolts.

D. GEAR TRAIN MAINTENANCE

D. (General) GEAR TRAIN MAINTENANCE
To Repair Leaking “U” Cup
The Actaris 2” Type 4-MT, MTSC and Type Seal Stuffing Box
4D-MT have the same gear train design and met-
allurgy. The procedures for repair and replace-
ment of these gear trains are exactly the same.

To Repair Leaking “U” Cup

Seal Stuffing Box

Keep dirt out of register and avoid injury

to gasket.

Remove the register. If tightening the stuff-

ing box nut with the fingers does not stop this
leak, replace “U” cup shaft seal. It may also be
necessary to replace “U” cup shaft seal and to
replace the gear train.

1. Remove the register. On flowmeters with

compensator, disassemble to compensator. On
flowmeters without compensator, remove the
register and the flowmeter cover.
2. Remove the star connection (1), using a No. 8
(5/64) Allen wrench.
3. Unscrew the stuffing box nut (2). FIGURE 20
4. Remove shaft seal (3). Inspect upper end of GEAR TRAIN ASSEMBLY
spindle to be sure it is free of nicks or burrs which
might damage the new shaft seal when it is placed on spindle. Remove the
clamp nut (6); gear train assembly can be removed from underside of flowmeter
cover or compensator.
5. Replace shaft seal with new part. Be sure expander (4) and spring (5) are
in position before inserting new seal.
6. Assemble nut and tighten down all the way.

To Replace Gear Train To Replace Gear Train

1. Remove the register.
2. Remove the star connection (1), using a No. 8 (5/64) Allen wrench.
3. Remove the flowmeter cover, with gear train assembly attached. Keep dirt
out of flowmeter and avoid injury to the cover gasket.
4. Unscrew the stuffing box nut.
5. Remove clamp nut (6); gear train assembly can be removed from u­ nderside
of flowmeter cover.

Page 21
E. TEMPERATURE COMPENSATOR MAINTENANCE (General) TEMPERATURE COMPENSATOR
Most 2″ Type 4D-MT LP-Gas meters are purchased with temperature MAINTENANCE
compensation devices, also called at ATC. Some 2″ Type 4-MT petroleum
meters are also being purchased with ATC, mostly in areas where the local
W&M ­authority permits the temperature compensated delivery of petroleum
products. The information following may be used for maintenance of ATCs on
either type of meter.

The Compensator is designed to give long and dependable service when To Repair Compensator
properly installed. The unit has been thoroughly performance-tested prior to
shipment, and in normal service requires no further lubrication.

Maintenance of the compensator should be limited to those operations

outlined below. If it becomes apparent that the unit is in need of repair, the com-
pensator should be returned to the nearest authorized Actaris distributor.

To Remove Compensator To Remove Compensator

1. Remove the register.
2. Remove cover bolts at the base of the compensator and lift the unit off,
taking care not to damage the gasket.

To Replace Compensator To Replace Compensator

1. Mount the compensator with the cover toward the front of the flowmeter.
Care should be exercised to set arm of compensator gear train so that it will
not come down on top of the piston spindle.
2. Make sure that compensator is down on gasket before tightening bolts.
3. Tighten all bolts (NOTE: See Torque Requirements and anti-seize compound
recommendations on Page 29).

To assemble a compensator on uncompensated flowmeters follow above

steps after first removing main case cover and replacing gasket, if necessary.
Re-use bolts taken from main case cover.

To Remove Compensating Mechanism To Remove Compensating

1. Remove two seal screws and take off “Neptune” cover. Mechanism
2. Withdraw anchor pin after removing cotter pin.
3. Remove three screws and take off lever arm plate.
4. Remove four screws around top edge of
compensator and lift off upper housing.

FIGURE 21
AUTOMATIC TEMPERATURE
COMPENSATOR COMPONENTS

Page 22
To Replace Thermostat To Replace Thermostat
1. Perform Steps 1–3 found under “To Remove Compensating Mechanism.”

CAUTION
Before opening any part of the flowmeter, close valve between sup-
ply tank and flowmeter. Disconnect coupling vent line at vapor release
cover. Perform the following outdoors, away from building or sources of
ignition:
Open valve slowly at end of delivery hose or other outlet piping. After
pressure is dissipated unscrew Vent Valve (hex. nut) slowly (maximum 3
turns) on top of Vapor Release to depressurize product in flowmeter.

2. Remove four screws and lift off thermostat cover.

3. Lift out thermostat being careful not to damage thermostat gasket.

F. PETROLEUM METER MAINTENANCE

1. DOUBLE TRIP MAINTENANCE (PETROLEUM METERS) DOUBLE TRIP MAINTENANCE

To Disassemble and Assemble Double Trip Valve To Dissassemble and

Assemble Double Trip Valve
1. Remove valve from flowmeter.
2. Remove two screws (A) holding retaining ring (B) at inlet of valve. (Cau-
tion: End plate should be held by hand when removing screws because of
spring tension beneath the plate.) All internal parts of the valve can now be
removed with the exception of the operating shaft mechanism. The removal of
the internal parts from the valve body may be assisted by operating the valve
handle as when operating the valve.
3. Disassemble piston and throttling ring assembly (items F to K). Inspect
valve seats, “O” ring gaskets, piston ring (D), and cylinder (C) for damaged
surfaces. Replace all defective parts with new parts.
4. Reassemble piston
and throttling ring assem-
bly. Apply Loctite Black
Max 380 to bond the disc
(G) to the piston (F), and
allow 24 hours to cure
before placing in service.
Apply Loctite Thread-
locker 242 under heads
of three piston assembly
screws (H).
5. Assemble pilot valve (E)
on pilot valve rod (J). Place FIGURE 22
assembly into valve body. VALVE ASSEMBLY
6. Place one end of spring
over pilot valve boss.
7. Place other end of spring over boss in cylinder (C) and press cylinder down
over piston (F). Back of cylinders should be below flange face for proper assembly.
8. Hold cylinder in place, place “O” ring in body recess and attach retaining
ring (B) with two screws (A).
9. Open valve as far as possible — make sure that valve is not being stopped
by set screw (L).

Page 23
2. OPERATING SHAFT MAINTENANCE (PETROLEUM METERS) OPERATING SHAFT
MAINTENANCE
To Inspect Operating Shaft Seals of Preset Valve
To Inspect Operating Shaft Seals
The following steps should be followed if it becomes necessary to disas- of Preset Valves
semble the operating shafts because of leakage. Shaft seal cannot be corrected
by tightening of the bearing bracket screws. In this case new “O” rings are
usually required. (See parts list for 2” Type 1A Double Trip Preset Valve.)

1. Remove valve handle (A), con-

necting rod arm, (I), two stop plates
(B) and (H) and two roll pins (C).
Remove eight screws and pry off
two shaft bearing brackets (D). Do
not damage gaskets (G).
2. The two “O” ring seals (E) can be
inspected for damaged surfaces.
Replace any defecting “O” rings.
3. To remove the operating shaft
(J) and two shaft bearings (D), first
remove the two screws in the valve
operating cam (K). Inspect the
shaft for score marks and replace
if necessary. New “O” ring seals FIGURE 23
are worthless if used with a badly SHAFT ASSEMBLY
scored shaft.
4. Remove retainer (F), replace “O” rings (G) and reinstall shaft bearings (D).
5. Reassemble the operating shaft and cam.
6. Replace rings, flat gaskets, two roll pins, two stop plates, connecting rod
arm and valve handle.

3. AIR RELEASE MAINTENANCE (PETROLEUM METERS) AIR RELEASE MAINTENANCE

General Note — “O” Ring Gaskets General Note — “O” Ring
Gaskets
1. The groove in which the “O” ring is located must be free of dirt.
2. The flat face against which the “O” ring seats must be clean and free of nicks
or dents which will allow pressure to leak between the gasket and the metal.

Optional Adjustable Back Pressure Valve

The 2″ Type 4-MT back pressure valve is designed as an adjustable two
position valve. The valve is factory set at 7.5 psi cracking pressure for most
applications including gasoline, fuel oil, and other light oils. It is recommended
that this lower setting be used to reduce strain on the system. For special ap-
plications, such as lube oils or other heavy oils, it can be easily adjusted in the
field to 15 psi cracking pressure by compressing a spring and inserting a cotter
pin at the pre-defined location. It is important to note that the higher cracking
pressure will significantly reduce the flow rate.
This compact valve adds only 1⁄4″ to the height of the meter, without add-
ing to lay length or requiring additional connections. It is designed to add back
pressure to the meter to increase air elimination during split compartment test-
ing. In some applications, however, the increase in back pressure may increase
spitting, so special consideration of individual conditions should be used before
installing this valve.­

Page 24
To Install Adjustable Back Pressure Valve To Install Adjustable
1. Remove existing socket head cap Back Pressure Valve
screws (1) and (2).
2. Carefully separate the top half of the
meter from the 2″ connector as shown
in illustration.
3. After properly setting the back
pressure valve to the desired cracking
pressure, (see Fig. 25 for adjustment
instructions), insert O-ring into groove
on under side of back pressure valve as
shown in illustration and then align back
pressure valve onto the 2″ connector.
4. Insert second O-ring into groove on
under side of maincase and carefully
set maincase onto back pressure valve
plate, aligning holes properly so that
new socket head cap screws can be
reinstalled. FIGURE 24
BACK PRESSURE VALVE
Adjusting the Adjustable Adjusting the Adjustable
Back Pressure Valve Back Pressure Valve
1. As shown in drawing, the valve is set at 7.5
psi (cracking pressure). This is done by turn-
ing the slotted hex nut which compresses the
spring until the end hole position is located and
secured with the cotter pin.
2. The valve may also be set at 15 psi (cracking
pressure) by turning the slotted hex nut which FIGURE 25
BACK PRESSURE VALVE
compresses the spring until the second hole po-
sition is located and secured with the cotter pin.

To Remove Standard Back Pressure Valve To Remove Standard

The back pressure valve is located at the bottom of the air release and Back Pressure Valve
strainer unit. To remove it:
1. Remove air release and strainer unit from the line by unbolting at inlet and
outlet flanges.
2. Remove both strainer sleeves and air release valve.
3. Hold block of wood (25⁄16″ diam.;) against back pressure valve by inserting
it through the top of the housing and knock the valve out.

G. LP-GAS METER MAINTENANCE

1. DIFFERENTIAL VALVE MAINTENANCE (LP-GAS METERS) DIFFERENTIAL VALVE

MAINTENANCE
CAUTION
Before opening any part of the flowmeter, close valve between supply
tank and flowmeter. Disconnect coupling vent line at vapor release cover.
Perform the following outdoors, away from building or sources of ignition:
Open valve slowly at end of delivery hose or other outlet piping. After
pressure is dissipated unscrew Vent Valve (hex. nut) slowly (maximum
3 turns) on top of Vapor Release to depressurize product in flowmeter.

Page 25
To Disassemble To Disassemble
1. Remove connecting tube at top of unit. Differential Valve
2. Remove 10 of the 12 cover bolts leaving 2 screws on opposite sides in
place.
3. Slowly remove last 2 screws while holding cover down to oppose internal
spring.
4. Disassemble diaphragm assembly as necessary to replace parts.

FIGURE 26 FIGURE 27
DIFFERENTIAL VALVE DIFFERENTIAL VALVE COMPONENTS

To Reassemble To Reassemble
1. Assemble diaphragm assembly. Differential Valve
2. Insert spring and diaphragm assembly into cover.
3. Align bolt holes in diaphragm with those in cover using 2 screws on opposite
sides, and engage threads of screws.
4. Mount cover assembly on valve body and assemble and tighten 12 screws
evenly.; Do not exceed 18 ft-lbs. torque, using a star tightening pattern. Then
retighten torque specification in a circular pattern.
5. Install connecting tube to elbow fitting.
Diaphragm Installation of Diaphragm

Page 26
 VI. TROUBLESHOOTING
A. LP-GAS METERS
1. Register Not Working When Liquid is Flowing
Bypass around flowmeter not shut off.
Ice inside register.
Loose register or worn gear train.
Register in need of repair.
Sheared key on Change Gear — caused by ice in register or mechanically
tight mechanism.
2. Leakage at the Stuffing Box
Worn shaft seal or spindle.
3. Chronic Leakage at the Main Case Gaskets
Dirty or defective seat or excessive shock pressure.
Defective gasket or loose bolts.
4. Unsatisfactory Flow Rate or Complete Stoppage of Flow
Obstruction in vapor vent line between differential pressure valve and vapor
space in tank.
Pump too small or inefficient.
Note: The pump must have sufficient capacity and efficiency to pump
against higher heads than are normally found in gasoline or fuel oil instal-
lations. This is especially true when the delivery nears completion.

Pump vapor bound due to improper installation of bypass relief valve or

restriction in suction line.
Pump bypass stuck open or spring weak.
High loss of head. (This is caused by too many valves and elbows and the
length, diameter and condition of the delivery hose.)
Pressure build up in tank being filled. Condition becomes worse as delivery
nears completion unless vapor return line (not recommended) is used or
vapor space type filling is used.
Blocked strainer, or piston in flowmeter stuck. Clean strainer and/or mea-
suring chamber.
Open valve in piping allowing liquid to circulate around pump.
Worn pump.
Vapor release valve fails to close.
Pressure build-up on vent line.
5. Under-Registration — Erratic
Dirt in the measuring chamber.
Badly worn control roller or diaphragm.
Main casing damaged.
Dirt under seat of measuring chamber (after cleaning).
6. Over-Registration — Erratic
Diaphragm in differential pressure valve ruptured.
Vapor release valve remaining closed, allowing vapor to pass through flow-
meter.
7. Consistent Over- or Under-Registration
Flowmeter in need of calibration.
8. Printing Not Clear in Cold Weather
Ticket carbon not suitable for cold weather use.

B. PETROLEUM METERS
1. Register Not Working When Liquid is Flowing
Bypass around flowmeter not shut off.
Ice inside register.

Page 27
 Loose register driving arm.
Register in need of repair.
Sheared key on Change Gear — caused by ice in register.
2. Leakage at the Stuffing Box
Worn shaft seal or spindle.
3. Chronic Leakage at the Main Case Gaskets
Excessive line or shock pressure.
Defective gasket or loose bolts.
4. Reduction in the Rate or Complete Stoppage of Flow
Pump bypass stuck open.
Air release valve fails to close allowing liquid to escape through the air vent.
An open valve in piping allowing liquid to circulate around pump.
Worn pump.
Blocked strainer due to sediment or frost.
Piston in flowmeter stuck, caused by dirt. Check strainer and clean mea-
suring chamber.
On gravity operation back pressure valve not removed from air release unit.
5. Under-Registration — Erratic
Dirt in the measuring chamber.
Badly worn control roller or diaphragm.
Flowmeter casing distorted or damaged.
Dirt under seat of measuring chamber at the outlet port (after cleaning).
Leakage around the flowmeter due to partly open valve.
On gravity systems leakage around the flowmeter throughout the air vent line.
6. Over-Registration — Erratic
Leaking valve in empty compartment causing an emulsion of air and liquid.
Air release valve jamming, allowing air to pass through the flowmeter.
Vent line from the air release valve plugged causing air to pass through the
flowmeter.
Leaks in the suction line such as at valve stems, pump packing or flange gaskets.
Air pockets in closed-end piping in the suction line.
Manifold or compartment valves only partly open causing excessive suction.
Suction piping too small causing excessive suction.
7. Consistent Over- or Under Registration
Flowmeter in need of calibration.
8. Liquid Leaking Out of the Air Release Vent
Improper operation.
Worn, damaged or defective valve unit.
9. Printing Not Clear in Cold Weather
Ticket carbon not suitable for cold weather use.
10. Valve Will Not Latch Open
Adjust valve connecting link.
11. Cut Off is Not Accurate/Preset Valve Closes Too Soon
Adjust the tripping point.
Adjust valve linkage.
12. Preset Valve Fails to Close
Dirt in valve piston.
Improper linkage.

Page 28
Torque Requirements Torque Requirements for Bolts
The 2″ Type 4-MT, MTSC and 4D-MT primary components (maincase, air/ Used in 2″ Type 4-MT and Type
vapor release and valves) are made of cast aluminum alloy. The bolts used to 4D-MT Aluminum Meters
assemble these components are made of steel, with a special zinc plating to
help resist corrosion. Aluminum is lightweight and durable for this truck delivery
application; however aluminum is sensitive to bolt and component overtorqu-
ing and overtightening. To avoid problems associated with these conditions,
follow the guidelines given below for all bolt tightening for these two meters:

BOLT SIZE AND TORQUE

THREADS PER INCH IN .–LBS. FT.–LBS.
7/16–14 264-336 22-28
3/8–16 264-336 22-28
5/16–18 144-192 12-16
1/4–20 96–144 8–12
Recommended
Aluminum itself is relatively impervious to corrosion, much more so than cast Anti-Seize Compound
iron or non-stainless steel alloys. To prevent possible seizing of the bolts,
Loctite® Anti-Seize Thread Compound No. 767 is applied to bolts during the
factory assembly of the meter.
Make sure that this or equivalent anti-seize compound is used when the meter
parts are reassembled after service to prevent bolt seizing.
NOTE: Vent line check valve should be assembled with loctite 567 thread
sealant or equivalent at a torque of 25–35 ft.-lbs.

Page 29
 2″ TYPE 4D-MT LP-GAS METER
DIMENSIONAL INFORMATION

DIRECTION OF FLOW/METER OUTLET

Accuracy of all Actaris Type 4D Custody Transfer Meters for use with LP-Gas and Butane meets or exceeds U.S. Depart-
ment of Commerce Standards Division Handbook 44 Parameters.

Page 30
 2″ TYPE 4-MT PETROLEUM METER
DIMENSIONAL INFORMATION

DIRECTION OF FLOW/METER OUTLET

Accuracy of all Actaris Type 4 Custody Transfer Meters for use with Petroleum Products meets or exceeds U.S. Depart-
ment of Commerce Standards Division handbook 44 Parameters.

Page 31
 2″ TYPE 4-MTSC PETROLEUM METER
DIMENSIONAL INFORMATION

Page 32
 METER MOUNTING TEMPLATE

DIRECTION OF FLOW/METER OUTLET

SCALE 1:1

Page 33
Page 34
 2″ TYPE 4-MT PETROLEUM METER
WITH NO DIFFERENTIAL VALVE DRAWING

Page 35
U.S.A./International
1310 Emerald Road
Greenwood, SC 29646-9558
Tel.: Toll-Free (800) 833-3357
(864) 223-1212
Fax: (864) 223-0341
© 2013 Red Seal Measurement   500   01/13

Specifications subject to change without prior notification.