Zexel Inline on cummins 3.3/3.9
 

The buys on the earthmoving side of the house have a 4 cylinder cummins in a Komatsu dozer. The engine started to haze badly, so they pulled the pump and nozzles to have them gone through.

The tech is trying to spill port time the pump according to the Cummins installation procedure, and the fuel stream never stops. I was asked to help out, and I have made 4 complete revolutions of the engine trying to be certain that the pump isn't out of phase, and it never stopped flowing fuel.

What would be the cause of this? I want to be certain we aren't missing something before the pump is pulled back off.

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Pump shop said to crack the throttle just slightly

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I thought that most or likely all Cummins inline injection pump applications used the inj pump lock pin ?

Do you have the ESN ?

Are you rotating Engine or pump? Is it possible that pump gear isn't fully seated and pump isn't turning

I didn't have the chance to go back to this. The gear cover was off and the pump was rotating.

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Fuel shut off On?

It was in the run position (key on)

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Is this a pump that bolts on from the top with for bolts? If it is during installation you can get the throttle/rack arm positioned all the way forward and everything looks perfect until you go to start it.

No, it's not a cartridge. I've done several of those. This a Zexel that looks similar to the body of an A Bosch or Delphi inline. It has screw in delivery valve holders like a Bosch. But no studs/nuts on top. I will try and get more info on Monday if I have time.

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Pull the side cover off of the pump and make sure the rack is moving when you turn the key on. Most "ag" type governors use a spring to pull them into a starting fuel position. Usually timing is done in full start position, with some exceptions. If the rack isn't moving either the spring is broken or the rack is sticking. If the rack is in a shut off position the fuel won't cut off. Also make sure if you pulled the center out of the delivery valve that the holder is torqued back down. If its not or the whole valve is pulled out then galley pressure will come out of the holder and it won't cut.