Timberman

I think I may have run my 4b cummins out of fuel. I filled the tank and pumped the hand primer about 1000 times. I cracked both 8mm bleeder bolts on the IP and get fuel out of each. I cracked the first two injector lines at the injectors, and I'm not getting any fuel from them while hand pumping, and very very little while cranking the engine.

Can someone please tell me the correct method for bleeding the system?

Also, how do you diagnose an IP failure on this motor?

Thanks

bigwheels94

Crack all 4 inj. lines, & crank it over. I'm assuming it is a late model with a rotary pump. Knowing the model would help.

Timberman

The plate on the engine block says its a model 4B-3.9. Has a mfg date 10/24/87. The IP is made by Delphi and was replaced just a couple months ago, before I bought the jeep.

bigwheels94

Without a ser # I don't know exactly what you have, but look for these things.
In addition to the throttle arm there may be another short lever on the pump. This is a shut off lever. Make sure it is free, & in the run position.
There may be a small plunger solonoid on the bottom of the inj pump with a wire going to it.(it may be on top too) This is the run solonoid. It can either be energise to run, or energise to stop. With the key on if there is voltage there it should be an energise to run, & may be stuck, or the plunger dammaged. Unscrew it from the pump. it should have a small plunger made of rubber. It should have no tears, etc.