new engine oil pressure going down

[betayv]

hello guys 1987 mercruiser 350, was rebuild, when start the engine oil pressure is about 40, when engine warm up pressure go down to 20 and bellow, If I accelerate the engine pressure goes to 50 -60, engine oil weigh is 25w40, new oil filter, any advice thanks.

 

[Alumarine]

Your oil pressure will go down when the oil gets hot. It gets thinner.
7-10 lbs per 1000 rpm is fine.

 

[achris]

hello guys 1987 mercruiser 350, was rebuild, when start the engine oil pressure is about 40, when engine warm up pressure go down to 20 and bellow, If I accelerate the engine pressure goes to 50 -60, engine oil weigh is 25w40, new oil filter, any advice thanks.

Sounds normal to me....

BTW, the oil pressure spec is 4psi (minimum) at idle, 30-60psi at 2000rpm.

 

[flipbro]

My new 5.7 runs 20 at idle at operating temp and a tad over 60 at wot

 

[biggjimm]

A lot of (most) guys get all wound up about oil pressure & hi volume pumps. Granted, not having pressure is definitely a bad thing but it doesn't need to be 80 psi at idle. In fact I have seen a couple instances where too high of oil pressure has actually blown cam bearings out. If you're main & rod bearings are in good shape or if the correct ones have been put in a rebuild, then a standard oil pump is more than sufficient. Your oil pressure sounds good. Enjoy that boat, summer is almost over, at least here in the midwest.

 

[achris]

A lot of (most) guys get all wound up about oil pressure & hi volume pumps. Granted, not having pressure is definitely a bad thing but it doesn't need to be 80 psi at idle. In fact I have seen a couple instances where too high of oil pressure has actually blown cam bearings out. If you're main & rod bearings are in good shape or if the correct ones have been put in a rebuild, then a standard oil pump is more than sufficient. Your oil pressure sounds good. Enjoy that boat, summer is almost over, at least here in the midwest.

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