Farymann genset oil pressure problem

[Restitution]

Our Farymann genny will run for 30 minutes, the shut down. It is not temperature related, but oil pressure. Engine starts well. Oil pressure is at 40psi. Gradually over a half an hour, oil pressure dips below 20psi. Once down to 14 psi, the oil pressure safety switch engages and rightfully, the engine shuts down. I tried 50 weight oil in lieu of prescribed 15w40. Same thing happens. Oil level on dipstick is between full and low mark. I’ve read where near full oil quantity may cause foam and low oil pressure. My next step is to reduce oil to low mark and see what happens. Oddly, the instructions say that engine runs best if oil is not topped off to full. Using high zinc oil. Do any of you men have some insight into this problem?

Thanks

Sam Nigro

[bayview]

Try blowing out the oil passages with the gauge out while cranking the engine..

[diver dave]

is the genset fairly level?
how does the oil on the dipstick look, foamy?
Is this a new problem?
Is the dipstick original?
Has a new oil filter been tried?

If all that looks good, then we might have to consider a plugged oil pump screen.

[bayview]

Sometimes there is a pressure control spring that is accessible without dropping the pan. cleaning or replacing that might help. Changing the filter is a good idea.

[kchace]

First thing is to verify that the oil pressure is in fact falling that low. It could be a sensor problem. Install a mechanical oil pressure gauge ON the generator and see if it agrees.

[timb]

I have one like that I think there is an oil strainer do you have a MANUAL . I have not ran mine much the surveyor said it didn't have any oil in it .I may have a pdf of the shop manual .I going to try to bring mine home next weekend .is yours on a dynamica gen set

[Ski in NC]

Shoot lower part of engine crankcase with an IR gun. See how hot oil is getting. I don't know what is normal for that thing, would not expect it to go over 180F.

Look in the manual for what is normal oil pressure. Some little engines lower oil pressure is normal.

[timb]

3. Oil pressure check The oil pressure depends mostly on the wearing conditions of the bearings. Before checking the oil pressure make sure that the oil level is topped and oil with correct viscosity is used. Remove the oil channel plug screw and connect oil pressure gauge with adaptor. Oil pressure values, hot engine ): Idle speed => min press. 0,5 bar ( 7 PSI ) Nominal speed => min press. 1,8 bar ( 23 PSI ) If oil pressure is to low first check the pressure relief valve before starting further dismantling of the engine.
15/18W – engines : Plug screw located on crankcase side.

[BruceK]

Oil pressure can be high while the oil is cold and thick and reduce as the
oil heats and thins. It could be a worn engine. Is it using oil?

[Restitution]

All good questions. Crankcase temp is 145. I’ve cleaned the screen strainer, to no avail. It is most certainly a decreasing oil pressure issue. Water is well within tolerance at manifold, head and antifreeze holding tank. Upon start, 40psi. Gradually drops below 15 psi over the course of 30 minutes. No oil filter on this engine and oil is NOT foamy on dipstick when run. The low oil cut off sending unit is working properly.

For an experiment, I tried straight 50 weight, thinking heavier viscosity would prevent the low oil pressure. It made no difference.

I would agree perhaps worn out bearings is the problem except for the fact that the disparity between high pressure and low pressure is 25psi?

I am hoping that the pressure relief valve/spring may be faulty? Or perhaps the oil pump?

Any additional thoughts?

Last year I had cranked the engine too long before it started and sucked fresh water into crankcase. I did clean that mess up and flushed new oil through several times back then. Perhaps some of the gummy residue put pressure releif out of commission? Never really ran genny last year after that.

I’m thinking of emptying crank case once again and flushing with diesel?

[Restitution]

Engine is not burning oil and seems pretty tight. It does have 800 hours on it.

[DavidM]

If oil pressure is 40 psi at startup and drops to 15 psi after running 30 minutes and 50 weight oil doesn't make any difference and you are not using oil, that sounds like an oil pressure relief valve problem, not the oil pump, the bearings or anything else discussed.

Don't know if that engine even has an oil pressure relief valve or how to get to it, but that is where I would focus.

David

[Restitution]

I am in agreement that the pressure relief valve is my next thing to check. Im wondering if perhaps the relief valve is 'clogged' from last years episode with sucking in water? Sure would save quite a bit of time and work to simply flush the crankcase with diesel. Either way, I am leaning toward the valve as the problem.

[timb]

let us know what you find I'm going to try to get mine out the bring it home this weekend . there is a access plate on the bottom you can pull the rod cap if it goes that far .

[timb]

[timb]

I got mine out do you have a parts source? I think it's where the oil smell was coming from.

[Restitution]

Yep. I ended up putting the genny project on hold for several weeks due to busy schedule and weather. Will pick back up on it in three weeks and let you know what I come up with. I plan to run some diesel oil in the crankcase in lieu of oil for a very short period of time to wash out. Then refill with Delo400 14w40. If problem persists, I will take out some oil to the low line on the dipstick as too much oil may be causing foaming. One way or another, I'll chase the problem down. Good luck with yours!

[Xsbank]

If you had water in the crankcase and then it sat the relief valve may be rusty. Try and take it out for a look.

[Restitution]

Exactly!!! I was thinking that diesel in the crankcase might unclog or free the relief valve up? Perhaps I should go directly to the source. Do you know where the relief valve is on the ferryman?

[Restitution]

Does anyone know where the pressure relief valve is on these Ferrymans?