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502 oil pressure

I've got a 502 in my boat. When I fire it up my oil pressure gauge is on 80 pounds. Right now I'm not running the boat on the water bc I have some parts to replace . But the engine is running. I'm just wondering if any of yalls 502 engines are at 80 at start up. I'm assuming when i actually get on the water and run it, that my pressure will drop after it comes to running temp? I have a new oil pressure sending unit, as my gauges are electric.
I'm going to replace that too. Bc I put all new gauges from jegs. Anyhow any input would be appreciated.
sender has to be matched to the gauge or it will read wrong, could try a mechanical oil pressure gauge connected where the sender is. A good mechanic should have one or you can buy one for like 40 bucks. checks your sender gauge combo to make sure its reading right.

Could be a relief valve stuck on the pump... 80 is quite a bit what weight oil are you running?
I believe it should be 5w20 if you’re running a zz502. Also sender must match ohms for particular gauge you are using. Just went through this getting a friend of mines boat dialed in. Brand new zz502 on his. It’s a hill climber now !! Zz is roller motor and calls for synthetic oil as well after break in period. Oil pressure drops after warm up
Just an observation here,,, 5W20 is recommended for fuel mileage in a car or truck,,,, you are virtually running an engine to it's full potential 75% of the time, I would suggest 15w40 Rotella or sae 40
I’m a bit confused. Is this a brand new engine or one that has time on it?

Oil pressure on a fresh build will be higher usually because of tighter clearances. As an engine wears the clearances open and oil bleeds out lowering the pressure.

With Chevy there are numerous pump options from stock to high volume. They also offer high pressure pumps. A fresh engine with a high pressure pump getting 80 would not shock me. An old engine with a standard pump using 5w-30 and that would make me think something’s not correct.
Its not brand new. It has about 50 hrs on it. I think the problem may have been bc I didn't install the the sender that came with the new gauge. (I went through installing new gauges. Oil pressure, water temp, & voltmeter.but I didn't put the new senders in for oil pressure & water temp. I did install those yesterday tho, so they are in now. And I did drain the conventional oil & put a new filter & filled it up with 5w30 synthetic.
Any time someone has an issue or concern with an oil pressure situation I suggest running out to Advance and picking up a mechanical gauge and giving the engine and electric gauge a reference point.

I personally only use a mechanical gauge plumbed with copper line.