Quote Originally Posted by tiorunder View Post
Got a 350 Malibu 1980. Motor was rebuilt with all new parts that fell within specifications. Oil clearances were where they were supposed to be (plastigauge). Motor runs very strong, but oil pressure drops to around 25 psi at idle when fully warmed up. Initial start pressure is right at around 60 psi. Along with the pressure drop I am getting valve train noise from BOTH banks and it is really pissing me off! Sounds like an oil pressure problem to me. Running a Fram filter and Castrol gtx 10-30. Looking for advice. Thank you in advance.

John from NC
Hi,
Your oil pressures are O.K. Does the motor knock in the first few
seconds after starting then cuts out? Has your engine block have a
removable blind plug alongside of the water pump area left hand side
facing the engine that generally would have a square head on it?
If so you can remove the plug and start the motor for a few seconds
and see what oil volume comes out.It should be a great powerful squirt.
With my Motor Oil--
I forgot to mention that the Valvoline was 20/50 was high detergent.
When Valvoline filters became scarce I tried a few others and then
changed to K&N which have done the job well. I change the oil about
5000 miles and It could go a lot further but I like to keep everything
nice and clean and lower the maintenance costs.You say the motor
runs strong- How strong and how often?? I Would like to see this
problem solved before it solves itself the hard way..Good Luck S/King.
P.S. I rarely push my ZZ4 past 4000RPM as there are no wide open
spaces in my local area...