TM 5-3895-346-14
ENGINE OVERHAUL
SHOP NOTES
If more than a 2% variation from the masters is noted, consult the calibrator manufacturer for possible causes.
The calibrated masters should only be used to qualify injector output calibration test equipment.
REFINISHING INJECTOR FOLLOWER FACE
When refinishing the face of an injector follower, it is extremely important that the distance between the
follower face and the plunger slot is not less than 1.645 inches minimum as shown in Fig. 5. If this distance is
less than specified, the height of the injector follower in relation to the injector body will be altered and proper
injector timing cannot be realized.
Figure 5. Injector Follower
FUEL LINES
Flexible fuel lines are used to facilitate connection of lines leading to and from the fuel tank, and to minimize
the effects of any vibration in the installation.
Be sure a restricted fitting of the proper size is used to connect the fuel return line to the fuel return manifold.
Do not use restricted fittings anywhere else in the fuel system.
When installing fuel lines, it is recommended that connections be tightened only sufficiently to prevent leakage
of fuel; thus flared ends of the fuel lines will not become twisted or fractured because of excessive tightening.
After all fuel lines are installed, run the engine long enough to determine whether or not all connections are
sufficiently tight. If any leaks occur, tighten the connections only enough to stop the leak. Also check the filter
cover bolts for tightness.
LOCATING AIR LEAKS IN FUEL LINES
Air drawn into the fuel system may result in uneven running of the engine, stalling when idling, or a loss of
power. Poor engine operation is particularly noticeable at the lower engine speeds. An opening in the fuel
suction lines may be too small for fuel to pass through but may allow appreciable quantities of air to enter.
Check for loose or faulty connections. Also check for improper fuel line connections such as a fuel pump
suction line connected to the short fuel return line in the fuel tank which would cause the pump to draw air.
Presence of an air leak may be detected by observing the fuel filter contents
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