Full Force

iTrader: (5)

Wonder how many guys don't check thrust or spin cam with just cam sprocket to make sure all is well...??

Boatally Insane

iTrader: (1)

So, Just a refresher..I've run it a bit and the oil pressure is really consistent regardless of filter or oil used..
65 psi at 4000 RPM. 50 psi at 5500 RPM. then back up to 65 psi once I drop the RPM's back to 4000 RPM


FINALLY got the engine out of the boat and pulled the pan.
Measured the oil pump pickup. looks like 1/2" on one side and 1/4" on the other.. so, while not ideal, not the worst...

HOWEVER, looking at the screen they used on the Summit pickup, looks like I may have found the problem...

Pictured next to a stock pickup...

Smitty

iTrader: (1)

I did not read the whole thread. I had what I would say is a very close story to yours. It was the check valve/bypass in the filter pad in block that was stuck halfway open. Had 75 psi cold start. Hot running of 65, then on roll back to idle speed,i t would drop to 20 and slowly come back up to 60 hot. My other motor was fine, so before I found it, I knew the oil was OK. So the end result was that since it was partly open, it bypassed the filter and cooler. $ 15.00 valve replaced and good to go. See if you have on pressed into the block.

Boatally Insane

iTrader: (1)

Thanks for the idea Smitty, but It's a Mark IV Dart block.. doesn't relief valves in the block. They would normally be in the filter adapter on a Mark IV block, however, I'm running the Hardin Marine "extreme" block adapter, and it doesn't have a bypass or relief of any sort. Only bypass I have is what ever is in the oil filter itself and the relief in the oil pump..

Baja Rooster

iTrader: (1)

I'm no engine builder, so what am I looking at in these pics?

Boatally Insane

iTrader: (1)

That is the oil pump pickup screen.. The square one is the Summit Racing brand installed on my engine. The round one is off a stock engine...

bobl

I'm a bit skeptical that would be your problem. There are still far more holes than the area of the 3/4 inch pickup tube it's feeding. I guess it's possible the size of the holes could be restrictive, but there are over 1000 of them! I notice there is a broken out piece on the far left of the pickup. Wonder where that piece of wire ended up? I was just looking at the pickup that came with a Hardin 502 pan I have. The holes in the screen are more like the original in size, but the pickup is only 2" in diameter. What are the dimensions on that pickup? Also, if that were the cause you would expect a lighter weight or hotter oil to improve the oil pressure since it would flow much easier.