Saturday, January 29, 2011

Cummins Diesel Engine Fuel Injection Pump Installation

The Cummins Diesel [Engine Model 'C'] fuel injection pump has been repaired, but there are still a few steps to take.

The fuel injection pump MUST be timed by removing threaded hex cap located on the throttle shaft side of the housing. Remove timing pin from access hole and rotate the pump by hand until the timing tooth inside pump housing lines up with the middle of the access hole.
Engage slotted timing pin as the picture above shows. Install threaded cap hand tight until after injection pump is installed. The injection pump is now in the proper timed position.

When a repair has been made on these pumps they must be pre-lubed with engine oil. Remove top plug from the governor housing with an Allen wrench. This particular model requires .71 Litres [24 oz.] . Failure to do this could cause damage during start-up.

The next step is to time the engine by rotating clockwise [viewed from the front] while pushing on timing pin until it engages into the camshaft gear. Engine is now properly timed, the fuel injection pump is ready to INSTALL.

After the 4 mounting bolts are tightened, torque accessory drive gear retaining nut to 106 in. lbs. then DISENGAGE BOTH TIMING PINS. The injection pump timing pin just pulls out, flips around and stays installed on the pump for next time. The engine timing pin just pulls back and stays put.

Now it's time for the final torque 144 ft. lbs. NOTE: torque specs will vary depending on the injection pump model. Now it probably makes sense to you why it's important to disengage both timing pins. They will sheer off very easily being made out of plastic and debris will get into the injection pump housing or engine timing gear housing.

Once the lines, linkages and accessories have been assembled it's time to bleed the system. Loosen bleeder plug located on the engine side of the injection pump. Operate transfer pump by hand until all air has been bled out of bleeder plug. Tighten bleeder plug.
Crack as many injector lines as you can at each cylinder and crank over engine until there is evidence of fuel at each injector. Stop cranking and tighten injector lines, start cranking engine once again and before you know it you'll have a smokin' diesel engine!


Anonymous said...

Hi, as a 2nd year diesel tech student, I'm rebuilding a isb engine. It has a hole in the head at the #5 valves, that has a plug and comes out on top. No one knows what it is or does, do you?


J. E. Whelan said...

I'm not familiar with that plug. It sounds like a coolant or oil gallery. The factory might have put that there for cleaning out or flushing the head properly? That's a wild guess....

Anonymous said...

Hi, me again, I took it to Cummins Northwest and they said that it is not a cummins thing but an oem that cummins built those engines for. Also that it's a qsb engine that is made for industrial equipment. So I geuss we learn a little bit every day.

Anonymous said...

I new in diesel class.
we have to tune-up Cummins diesel engines a, B C M-11 L-10
Detroit Series 92,60, 50, 50 CNG
3406 6 cylinder engine.
Need to have specs for these models and can find and the information. What does a tune-up from a gas engine to a disel. thanks if you can help!

HELP said...


Can you call or email me? I need an expert opinion on removing a fuel tank.



Quality Used Acura parts said...

well! i have no idea about engine repairing but now i understand is very informative post for me.
Thanks for sharing.