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To Adjust Rate of
Closing of Valve
To Inspect Operating
Shaft Seals of Preset
Valves
MEASURING CHAMBER
MAINTENANCE
To Remove And
Disassemble
Page 10
To Adjust Rate of Closing Of Valve
Variations in the viscosity of the liquids being measured will cause changes in the rate of closing
of the valve from its full open position to its intermediate position. (Valve should reach its intermedi-
ate position with approximately 4 gallons remaining on Preset setting wheels.)
Setting of orifice plate is indicated on tag attached to valve.
The rate of closing can be adjusted by changing the position of orifice plate which is readily
accessible through inlet of valve. (Valve does not have to be disassembled.)
(Figure 10) View of valve inlet showing position of orifice
plate for gasoline and other low viscosity liquids. Note that ori-
fice opening is completely covered. (Photo shows 1
1
⁄
2
″
valve.)
The normal position of orifice plate in valve to be used with
gasoline or other low viscosity liquids will be set with orifice open-
ing covered. If valve closes too slowly with this setting, turn plate
counterclockwise to expose either small, medium or large hole
as required.
To Inspect Operating Shaft Seals of Preset Valve
The following steps should be followed if it becomes neces-
sary to disassemble 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 the valve handle (A), connecting
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 defec-
tive “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). In-
spect the shaft for score marks and replace
if necessary. New “O” ring seals are worth-
less if used with a badly 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.
MEASURING CHAMBER MAINTENANCE
To Remove and Disassemble
This operation is not difficult and may be performed by any competent 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.
FIGURE 11
SHAFT ASSEMBLY
FIGURE 10
VALVE ORIFICE PLATE