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Topic: Cant Start Motor (Read 944 times) previous topic - next topic

Cant Start Motor

Hey folks,

I think i know why my u270 Cummins 8.3 wont start.  The O rings on the fuel filter were not replaced when I did an oil change a month ago.  I ran the unit for 400 miles post oil change but since that trip the unit has sat now for a month.  I will replace the rings on Racor Winn filter however I am not able to find the low pressure air screw to start the air purge.  Also is it necessary to purge the high pressure system..I want to make sure I get this primed properly. Never had this issue before.  Suggestions?

Chris

Re: Cant Start Motor

Reply #1 –

We don't change fuel filters at each oil change. About every other year is fine with me. It reduces start-up problems that can happen with each fuel filter change.
I don't see why not changing O-rings would give you this problem.

Priming is done on our coach by continuous pushing a rubber covered pump on the lift pump located on the curb side of the engine. I have used a flat board to help push from inside the lifted-up bed. After a while the pump gets harder indicating less air in line. Air gets pushed out of injector pump into fuel return line.

Is your fuel shut-off solenoid fully opening when you crank engine? This solenoid is on curb side upper rear side of engine and has linkage that rotates open on crank and stay open on ignition.
This solenoid is the only thing that stops a running engine when ignition key is turned off.
Engine will not start if solenoid does not lift to allow fuel flow.

Re: Cant Start Motor

Reply #2 –
Berry,

Great advice..thank you. Is the linkage easily seen when the engine is being cranked?  Is the part easily  replaceable and how does that part go bad....just curious.  thanks again.

Chris

Re: Cant Start Motor

Reply #3 –

Easy to see fuel shutoff on curb side. It can manually stroked open when engine is off.
Goes bad:
With un-lubricated linkage that keeps solenoid from lifting. From a failed solenoid that does not lift when ignition key is in starter position.
When a missing cotter pin allows the horizontal shaft to jam at an angle in the solenoid connector, which prevents the fuel valve to fully open, which causes the engine to only put out low power due to restricted fuel flow.