The last time I ran my boat, I noticed the oil pressure guage reading somewhat lower than normal. I have an electric guage on the dash, however, I have a mechanical guage mounted on the engine, both read identical. The engine is a 540 with 70 hours of hard running. My oil pressure used to be about 30 psi at idle after a hard run and about 70 psi while running. Now, it seems to have droppped 10 psi across the rpm range. 20 psi at idle after a hard run and 60 psi while running. I use Mobil 1 Gold Cap synthetic, have a real good oiling system and cooler. I also have an ESP Pre-Luber. The engine sounds fine, no noises. Today, I changed the oil and filter, same results while running. I just cut the filter open and found this. It is about .010" thick, it sticks to a magnet. I have never seen something like this in a filter. Any ideas? There was nothing else abnormal was found in the filter.

could that be a piece of oil pump gear tooth?

Had to come from between the oil pump screen and filter,no way that would fit through the pickup screen

Drop the pan and check the pump. Put the piece on the gear to match it. If nothing else missing your OK. If there are other parts missing, tear it down.

Hopefully just a bad pump. Smart to check the filter. I do at every oil change. Even if you have to tear it down, its only a thousand $$. Blow a motor and it could be 5 - 6K

I think the metal is too thin to be part of the oil pump gears. Doesnt seem to have peeled off the gears. I agree, something that big could never pass through the oil pump pick up screen. Nor could it pass through the mains of the block. But, remember, I have an ESP Pre-Luber which picks up oil from the bottom of the pan, no screen. The Pre-Luber sends the oil directly into the filter. I dont think that big a peice can pass through the tiny gears in the Pre-Luber either. If it did, I would think it wouldnt build any pressure on the Pre-Luber. When you have this piece in your hand, it looks like a piece of tin from the inner lip of the timing chain cover. But how the hell can that come off? I doubt that is the case. Also, what about the 10 psi drop of oil pressure I am noticing? If this piece went through my Pre-Luber and simply got trapped in the filter, the oil pressure should not have changed. If I had no change in oil pressure, I would swear this piece was in the filter before I screwed it on.
Hey, i just thought of something.... I have a check valve between the Pre-Luber and my filter head. Maybe it came from there?? That would explain the sudden drop in oil pressure. When the engine is running, the job of the check valve is to keep the oil and oil pressure in the filter head. If the check valve is coming apart, it will be leaking or bleeding oil back through the Pre-Luber and into the oil pan.
I know what I will be checking first thing tomorrow.

How did a pencil get in your filter??

Vinny,
How about a picture of that thing from a different angle ? Sure looks like a pc of gear to me, but its hard to tell from the picture. Is it magnetic ? Could it be part of a the distributor gear ?

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

Looks like a tooth from a bronze distributer gear to me, but that would not explain your oil pressure drop

That was my thought. At least it looks bronze in the pic.


Darrell.

I don't think bronze is magnetic. That is what it looks like though.