Chev Oil Pressure

[Jakevr4]

Hey guys,

My rodeo has started having hot oil pressure problems. When it is cold it has 80+psi of oil pressure, when it is hot the pressure is fine when cruising under 80kph, bump it up to 100 (3300rpm) and the pressure gauge flickers around. If I hold it pinned it drops to 0 and doesn't recover until I lift.

Engine is a fairly worked 350ci small block chev, just want to get some ideas on where to start.

 

[trotty]

Could it be a weak relief valve spring in oil pump. ?

It's very odd to drop pressure like that without it bypassing somewhere.

 

[Jakevr4]

hmm hadn't thought of that, this is all of a sudden as well, if the spring has broken the pressure would be high when the oil is cold/thicker ?

I have to pull the motor out for access anyway just trying to get an action plan for when it is out.

 

[6A13TT TYPE S]

You can take the dizzy on on a small block and use a cut off screwdriver in a drill to spin the oil pump. Doing that may indicate if theres a fault with the pump or releif valve.
But sounds like a faulty sender to me.