TM 5-3810-289-34
indicated that this continued pressure is necessary to
make certain the entering flat face of the governor barrel
maintains contact with the housing when both the
housing and barrel have cooled. There is a tendency for
the governor barrel to "pop out" approximately 0.010-
0.030 inch out of the heated housing.
(7) Select a new Class 2 (green color code)
plunger and attempt to fit it in barrel, if plunger enters, try
a Class 3 (yellow). Keep trying larger sizes until one will
not enter barrel, then select one two sizes smaller for
use. Plunger must drop into bore of its own weight.
Lapping may be required to obtain desired plunger fit.
Use caution and clean thoroughly if lapped. See table 2-
(8) Brush plunger lightly with crocus cloth to
remove any lubrite crystals.
Figure 3-68. Center line being scribed on governor
(9) Check plunger fit with a new fuel pump
barrel.
assembly as a fit comparison.
(10) If lapping is necessary, see steps 2 and
7 above.
(11) Install spring dowel into bottom of
barrel with ST-853 Driver with slot of pin to front of
housing, figure 3-71.
Figure 3-69. Center line being scribed on fuel pump
housing.
c. Installation.
(1) To locate a new governor barrel in the
housing, scribe a center line on barrel and housing, lining
up the fuel passages so fuel now will not be restricted,
Figure 3-70. Current PT (type G) governor plunger.
(2) Heat housing in oven to 300 F.
3-11. Fuel Pump Filter Screen
(3) Cool barrel in dry ice or other method.
a. Removal Refer to paragraph 3-2 c (10).
(4) Coat new governor barrel with high
b.
Disassembly.
There are two screen
pressure lubricant.
assemblies. The top screen cannot be disassembled,
(5) Drop spring pack housing in place.
but the bottom one can, figure 3-65.
(6) Place governor barrel in housing bore
c. Cleaning and Inspection.
with chamfered end first and location pin hole on bottom
(1)
Clean upper and lower screen
side, lining up scribe marks, then press barrel in housing
assemblies and retainers in fuel oil and dry with
with arbor press until it bottoms against spring pack
compressed air.
housing. This is important to aline barrel retaining pin
(2) Inspect screens for breaks or holes in
holes. Scribe marks must aline within 0.040 inch to
mesh or other damage.
assure indexing of the vent holes.
(3) Replace worn or damaged parts.
Note. When installing the governor barrel into the
d. Assembly and Installation.
heated housing, the pressure applied to governor barrel
should not be released for 15-20 seconds after the
governor barrel is pressed into the housing. Tests have
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