DETROIT DIESEL 53
FUEL INJECTOR TIMING
INJECTOR TIMING GAGE CHART
Fig. 1 - Timing Fuel Injector
To time an injector properly, the injector follower must be adjusted to a definite height in relation to the injector body.
All of the injectors can be timed in firing order sequence during one full revolution of the crankshaft. Refer to the General
Specifications at the front of the manual for the engine firing order.
Time Fuel Injector
After the exhaust valve clearance has been adjusted (Section 14.1), time the fuel injectors as follows:
I. Place the governor speed control lever in the idle speed position. If a stop lever is provided, secure it in the stop
2. Rotate the crankshaft, manually or with the starting motor, until the exhaust valves are fully depressed on the
particular cylinder to be timed.
If a wrench is used on the crankshaft bolt at the front of the engine, do not turn
the crankshaft in a left-hand direction of rotation or the bolt may be loosened.
3. Place the small end of the injector timing gage (refer to the chart for the correct timing gage) in the hole
provided in the top of the injector body, with the flat of the gage toward the injector follower (Fig. 1).
4. Loosen the injector rocker arm push rod lock nut.
5. Turn the push rod and adjust the injector rocker arm until the extended part of the gage will just pass over the
top of the injector follower.
6. Hold the push rod and tighten the lock nut. Check the adjustment and, if necessary, readjust the push rod.
7. Time the remaining injectors in the same manner as outlined above.
8. If no further engine tune-up is required, install the valve rocker cover, using a new gasket.