Ok heres my situation bought a 1997 z28 6sp and was supposed to have a bad opti ..took off the opti cap to find a burnet rotor so replaced it and car started right up BUT had little if no oil presser at idle when reved would go to 15 to 20 max .So drove the car and power was fin no knocks but the drivers side up valve train was ticking ..Pulled the cover to find little or no oil getting pumped up through the pushrods ...So i pull the pan and theres a brand new hv oil pump on the motor ...so now im thinking the drive gear is stripped pull the intake and drive gear is fine ..OK so now i pull the oil filter cut it open to find aluminum looking metal flakes throught it ..and never pulled a cap when i have the pan off cause finding the hv pump on a stock oil pan motor but the pump was brand new .so i put a m155 with the high pressure spring in it ..Well in stumped if i had a spun bearing would'nt i hear it ..Now i did find a bad hermonic balancer that had wooble enough to scare the opti cap ..So my question is with no bottem end noise rattleing or knocking but no oil pressure could it be a bad cam bearing maybe due to the woobeling balancer ...

 

Did you check to make sure the pickup was picking up the oil properly in the pan??

Maybe you got some clogged oil passages for some reason.

I put a high flow pump on mine tanked, new bearings LT1 and I got damn near 80 pds pressure at start up and 65 to 70 at idle when warm.

 

Yes i put a new pump and tack welded the pickup .Just wierd thougt a spun bearing would make low bottem end noise.Or could all the bearing be shot but not spun there causing no oil pressure or a cam bearing maybe could a bad cam bearing cause no oil pressure at idle

 

A spun rod bearing make a knock like a small hammer on a heavy vice. A main bearing knock is like a sledge hammer on the same vice..a heavy think. They both increase and decrease with engine rpm.

The balancer is on the end of the crank. I don't see how that can ruin the cam bearings. What's wobbling..the outter ring or the whole thing. Just the outer ring and you just replace the dampr and it goes away, the whole thing and something else is wrong....

Oil pressure is basically governed by the cam bearings clearance. As those clearances increase the oil 'leaks' out of the bearing. Here's the thing...sometimes you don't hear the bad cam bearings because the reciprocating forces are much smaller than those on the crank.

Sorry, but I think you have a big problem. Low, but not no, oil pressure says the pump is still functional. .....

Good luck!

 

I was thinking cam bearing cause theres no knock or rattle and theres little or no oil pressure and no copper just aluminum looking metal..

 

did ya check it with a manual gauge yet????????i have seen a few pressure sensors go and only read at higher rpm,s.....and if ya had no oil pressure ya would hear the car knockin like a trick or treater

 

well never let the gage stay at bottem .just keep it at high idle wial running it at about 10 to 15 lbs of pressure 20 max wial reving it up ..when you let off the peddle it drops to 0 but as i said never let it run more than a sec at 0 pressure..and the bottem end is totely silent no noise drove the car power is fine just no oil pressure ..and to lose all pressure at idle will be pulling timming cover this next weekend..hope its just a cam bearing ..the motor has 81000 on it and the cyl walls look like it was just assembled crosshatches look just done ...no wear at all...

 

You should check it with a manual gauge before you start tearing stuff apart.

To have 0 pressure and run fine and no knocks sends red flags on the gauge to me.

 

But theres no oil gettingto the top end of motor nothing through the pushrods on the drivers side very little on passenger side..

 

15-20psi is nowhere near adequate pressure at higher rpm. You should have just shut it down at that point and not driven it. At least not without checking the pressure with a mechanical gauge. I doubt you're going to find any different results with the mechanical gauge though. Sounds like time for a rebuild.

 

yea thats what i was thinking ..Well i least i will know what i have then ..Thanks to all who have responded ..Updates comeing soon..

 

When mine kicked the bucket the top end driver side was "ticking" heavily, could hear it and feel it from inside the car.

 

bombebomb what went a main or a rod or the cam bearings..?