Oil pressure very low; Pull the engine?

[geekeasy]

It's an electrical gauge.

I trust it somewhat.

And if there is an accumulation of foreign matter in there, which there very well may be, any suggestions on cleaning it out?

Thanks again for your help everyone. I've spent the last few years learning how to maintain and repair my boat, and this is the first time that I'm really delving into the engine -- I've got a lot to learn.

[hanleyclifford]

One thing I have learned about cleaning out such passages is that the gun store is our friend. I keep an assortment of bore cleaning brushes in my tool kit for this kind of cleaning. In fact the bore cleaning solvent itself is surprisingly effective.

[geekeasy]

One more question - is it worth trying to reinstall the original old style valve - with the new gasket and spring to see if I get different, and better results?

[hanleyclifford]

One more question - is it worth trying to reinstall the original old style valve - with the new gasket and spring to see if I get different, and better results?

In post #13 you mentioned that you have already installed an old style valve (cone type).

[geekeasy]

In post #13 you mentioned that you have already installed an old style valve (cone type).

Sorry about that.

I meant would it be worthwhile trying to reinstall the original ball bearing type valve, along with the replacement spring and gasket to see if I get different/better results?

[hanleyclifford]

Sorry about that.

I meant would it be worthwhile trying to reinstall the original ball bearing type valve, along with the replacement spring and gasket to see if I get different/better results?

No harm, but while it's out you could try to do a clean out with whatever tools you have at hand. Note that Moyer Marine sells a kit for cleaning up the seat. Most members report better results with early cone style, however.

[geekeasy]

Oil Pressure too high when cold; too low when warm

I did not replace the gauge with the ball bearing valve, but I just took the boat out on a 45 minute motor test run.

New symptoms:

When cold, the oil pressure gauge reads too high: 75.

When warm, the oil pressure gauge is too low. It gradually drops from 20 down to almost nothing.

However... the engine temperature stayed at an constant 160 degrees.

With those symptoms, it seems likely to me that the gauge malfunctioning. Do you agree?

And if so, is there any way to easily check if the problem is with the sender, the gauge, or even the wire?

Thanks for all the help!

[Marian Claire]

When you removed the adjustment spring and ball did you dress the seat as suggested in post 21? Dan S/V Marian Claire

[geekeasy]

When you removed the adjustment spring and ball did you dress the seat as suggested in post 21? Dan S/V Marian Claire

I did not. But it seems that if the oil pressure really is dropping to almost nothing, then at minimum the engine would heat up, right?

I just ruled out the wire as the problem. I replaced it, and am still getting the same results.

I also double checked the oil and the oil level; both looked fine.

[Marian Claire]

I can only say that every time I have had an falling oil pressure issue dressing the seat cured it. More than once for no apparent reason the OP would start to drop. I can adjust mine on the fly and have been able nurse it thru the day. Only after removing the adjustment and dressing the seat did the OP stabilize. Note: I have the early style cone type. Have you tried adjusting while the engine is running? If so what happened? As others have said it could just be the gauge. Dan S/V Marian Claire

[geekeasy]

Woo Hoo!

Thanks for your help everyone.

I _think_ I fixed it. Based on Marian's comments that it's likely a seating issue, I did go back to the original ball bearing valve. It, along with a new gasket and new spring, seems to be giving consistent readings at 40.

I won't know for sure until I try it out tomorrow, starting it completely cold and motoring it for a while, but it's definitely looking much better.

[geekeasy]

Nope, not fixed.

Nope, not fixed.

Unless anyone else has any other suggestions, I guess I'll try the seat dressing tool next.

[hanleyclifford]

After re-reading the thread I'm still not sure you are getting accurate oil pressure readings. You need direct pressure gauges tapped right into the holes provided in the block. Electric gauges, especially old ones, are for tourists. The question to be resolved is this: does your oil pump deliver sufficient pressure to operate the engine? In connection with this, can you tell us how many turns out from seat you are running the oil pressure regulator valve?

[joe_db]

+1
I redid my fuel system end-to-end TWICE to find out I was having a gauge issue
First step is to get a good mechanical gauge.

After re-reading the thread I'm still not sure you are getting accurate oil pressure readings. You need direct pressure gauges tapped right into the holes provided in the block. Electric gauges, especially old ones, are for tourists. The question to be resolved is this: does your oil pump deliver sufficient pressure to operate the engine? In connection with this, can you tell us how many turns out from seat you are running the oil pressure regulator valve?

[geekeasy]

+1
I redid my fuel system end-to-end TWICE to find out I was having a gauge issue
First step is to get a good mechanical gauge.

There's now one in the mail. I'll let you guys know what I find out after I plug it in.