Oil pressure fluctuating at idle
 

The oil pressure on a chevy 350 is fluctuating at idle. It does not matter if the engine is warm or cold. I always have oil pressure. Engine sounds like a sewing machine. Maybe a bad lifter. Thoughts?

Re: Oil pressure fluctuating at idle
 

Bad lifters and several flat cam lobes!
Pop off the valve covers and check movement of the rockers.

Re: Oil pressure fluctuating at idle
 

How would I check movement of the rockers with the valve cover off? Should I have the engine running? What should I be looking for?

Re: Oil pressure fluctuating at idle
 

Easiest is valve cover off and engine running. It WILL be messy! Do one side at a time. Check for all rocker tips moving about the same amount. If one isn't moving much, that is your suspect.

Might cut open your oil filter and check for metal bits. Not definitive as a bad lifter doesn't normally make many metal bits and a worn cam lobe might have failed before your last change. If you find a bunch of metal, something is failing.

What is your idle speed? A stock SBC will often idle smoothly well below the recommended idle speed. Too slow can show some oil pressure variations.

Re: Oil pressure fluctuating at idle
 

There is fast idle and curb idle. Curb idle is at 700 rpm. Fasts idle is at 950rpm until the engine warms up and I kick down the idle cam.

The fluctuating engine oil pressure happens consistently. At either idle and when the vehicle is running at speed. Also the engine has sat for about 10 years with little use.

Re: Oil pressure fluctuating at idle
 

Is this an electric gauge?

Re: Oil pressure fluctuating at idle
 

Yes

Re: Oil pressure fluctuating at idle
 

What oil filter is on the truck? and sometimes fluctuation can mean the oil level is low

Re: Oil pressure fluctuating at idle
 

Wix 51061

Re: Oil pressure fluctuating at idle
 

I pulled the oil filter and examined the internals. I don't see any metal debris. There is carbon like chunks in the pleats. It has about 30 miles of driving time with the engine oil. I also used an additive to the engine oil.

Re: Oil pressure fluctuating at idle
 

Carbon like chunks doesn't sound good. Any pics of them. Also,.... unbolt the small aluminum adapter that the oil filter screws onto and see if the spring loaded check valve is not messed up or has one of those 'chunks' stuck in it