MEP 003A: No Oil Pressure

[rosie]

Guys, I know this subject has been beaten to death--but I have a unit with 42 hours on the meter that was running perfectly in an emergency situation running the pumps for the entire water system for a private school. It ran about 3 hours then shut down abruptly. First check--oil was honey gold and there was plenty of it. It re-cranked instantly, started, but still had no oil pressure. Reading all the posts it appears it could be the oil pump or oil pressure relief valve. Short of having to pull the motor, has anyone else experienced a similar situation and can give possible ideas to try before tearing the whole machine down?

Many thanks.

 

[m-35tom]

have you checked it with a known good gauge? a mechanical one right on the engine?

 

[glcaines]

Rosie, the 003A has a mechanical oil pressure gauge. Before you do anything else, I would confirm that the unit actually doen't have oil pressure. If you don't have a spare gauge, go to any auto parts store and purchase the cheapest pressure gauge you can find that you can attach the hose to. Don't start the unit, just turn it over and watch the gauge. If you show pressure, then replace the oil pressure gauge. If not, you already have an idea of what to check next. By all means, don't start the generator again until you confirm that you have oil pressure. If there is no oil pressure, it sounds like you may have gotten lucky and not locked up the engine. Could still be damage though.

 

[cuad4u]

I assume that "no oil pressure" means the low oil pressure switch shut the engine down AND the oil pressure gauge read zero. If the engine just shut down it could be a defective low oil pressure switch. If the mechanical gauge shows zero pressure it could be a defective gauge. If your generator shut down because the low oil pressure switch opened AND the gauge showed zero, you definitely have an oil pressure problem. If only one of the two things happened, I would look for either a defective gauge or a defective low oil pressure switch.

 

[m-35tom]

or they could both be bad, we are talking about old units here.

 

[Rapracing]

I had a wire loose on my pressure switch one time that caused the same thing. Clean and tighten wires/connections as well

 

[Jimc]

yes definitely listen to these guys and check the gauge and pressure switch first. both the oil pump and the relief valve are a real pia. the relief valve is behind the flywheel so you need to pull the gen off the motor.

 

[rosie]

Continuing with no oil presure problem

Guys, thank you so much for your input(s). I will definitely check everything especially the electrical connections. I feel that at the moment I will take the oil pressure gauge off, and crank it over; if oil comes out I'll know the pump is doing its thing.

Unfortunately I feel I may have problems given that it was running, stopped, and is more than willing to want to run, but low oil pressure is keeping it from doing so. Really hate to think of pulling the thing apart. All help is greatly appreciated.

For some reason my replies to the thread have not been showing up on the site, and I wanted to let you all know that I have read your suggestions and will be trying them out this weekend. Keep your fingers crossed for me!