High oil pressure

[cruzman]

I have a 2003 Volvo Penta 5.7. The engine runs fine but the oil pressure follows the throttle. At idle the oil press is 35. As the throttle is increased the oil press increases up to 80. Oil level is good and it looks fine.What regulates the pressure?

 

[RicardoMarine]

The SBC oil pump is a dual gear Positive Displacement type pump.
It is capable of pressures up to 1k +/- if the relief valve would allow it.

This same relief valve controls pressure to a nominal 45-70ish range when the oil is cold (depending on oil viscosity).
As the oil viscosity changes with operating temperature, it should be more like 45-50ish max.
Some of the experts suggest that any pressure greater is unnecessary and not recommended for our SBC marine engines.

Years ago Bill Jenkins wrote a great article on SBC oil pressure and cavitation.
While it mainly pertained to high performance engines, the theory could be used for any SBC.

......

Wish that I could find that article.

I'd be willing to bet that either your gauge or sender is faulty.

 

[cruzman]

Thanks. I will start with the sender. Where does this regulator live?

 

[RicardoMarine]

Where does this regulator live?

The pump's pressure relief is part of the actual pump.
It cannot be accessed without oil pan and pump removal.

 

[cruzman]

Thanks.