M939 NHC240 Fuel Delivery Issue

My 5-ton has not run well for awhile, sometimes seeming to starve for fuel or losing prime. A couple of days ago, it stalled and woudn't restart. Yesterday, cleaned fuel lines, removed fuel filter and can blow fuel from tank to injector pump. Reconnected everything and still won't run, except on ether. Jumped solenoid on injector pump while turning over and will fire and try to run. I'm thinking I want to replace that solenoid. Is it 24v or 12v? Any experience with this solenoid failing? Thank you very much!!! Frank

Mine is still bad on the 816 and I just ran the thumb screw in for now and use the emergency shut down cable. If I remember 24 volt and you could check to see if your getting full voltage to it and good ground.

Probably the fuel line in between the filter and the injection pump. Will not show leaks or wet spots. Will lose prime, not start, and finally won't run. The line dry rots, has very small cracks, which allows air to enter and the system won't stay primed.

Replace the line.

Great tips you two! Will do both. Thanks!!!

Easy with the starting smelling salts, it likes to loosen carbon and stick rings.

Floridianson, I hope to try your fix/bypass tomorrow. I don't have much experience with the emergency shut down cable. Do you have to open the hood to reset it for every restart? Thanks.

As configured, yes. Install another cable lock on the other side and you can turn it into a push / pull arrangement.

Copy that...thanks again!

Well I installed two cable locks fore and aft and have been adjusting. If the objective is to move the injector pump lever through the full range, i.e. 45 degree towards front and 45 degrees to the rear then I have a problem. I can pull the emergency stop lever in the cab to obtain the 45 degrees towards the rear, but can only push the injector pump lever to almost vertical before the cable bows without pushing the lever to the 45 degrees to the front. I am considering bolting in an 8" piece of bar stock to tie the floppy, shielded cable end to, to stabilize the cable thus curing the bowing. Thoughts? Thank you!

A spring to pull the emergency shut down back to the run position when you push the shut down cable back in.

Floridianson said:

A spring to pull the emergency shut down back to the run position when you push the shut down cable back in.

Click to expand...

If you don't have another cable lock, a zip-tie also works to make it a push-pull deal in a pinch.