Looking for some input from you smart guys.

My 2001 has a built engine (I popped the piston on the first one with a supercharger a while ago).

Car ran fine with the new motor, albeit noisy with a quirk or two for about 2-3 years. Got off the highway after running it hard one day, and the oil pressure seemed unusually low. It’s often lower than usual when you stop at the end of the off ramp, ‘cause the motors good and hot, but this was unusually low for what I was used to seeing at idle. Say maybe 25 psi. I have never seen it drop below 35-40 that I can recall.

Over the next several weeks, the oil pressure when hot and idling seemed to decline steadily. Just before winter, the lowest I saw it hit was 19 psi. Since it was winter, I brought it in to the builder for a good check-up.

Other than a few mechanical issues, like a noisy supercharger pulley, they couldn’t find any deal breakers. The day I was going to pick it up, the shop foreman said it sounded funny that morning, and he wanted to pull the heads.

One of the roller lifters died and grooved one lobe of the cam pretty good. New lifters (the kind recommended on here), and a new cam.

Car sounds pretty good now, only it certainly has a new sound. Almost freight train like.

Hopped in and drove it to the office yesterday. Oil pressure hit 15 psi at idle, and I wasn’t running it on the expressway yet!

So now I’m a little nervous. What could cause these oil pressure issues and be so difficult to detect? What kind of oil pressure do you guys see at the lowest? Engine maybe has 20-40k on it.

Your thoughts please?

 

My stock motor after my cam swap makes around 35-40 warm idle, even after driving for like 1+ hrs. Lowest I have seen is like 30-32.

I did see 19 right after my cam swap, then I pulled the pan off and pulled the pickup tube off and re-aligned it to insure the o-ring wasnt kinked and I get 35-40 now.

I would first check your oil pressure sensor, then change the oil and filter to insure the filter isnt plugged (ive had this happen before)

the pull the pan if all else checked out fine

Does it go up with RPM?

Jay

 

yes, it goes to about 40 psi with rpm, but there is a significant delay.
35-40 is what I expect to see normally.

I will try changing the oil, and will look into determining if the gauge is shot.

If that seems to check out, I'll aske the shop to pull the pan.

They only share some of my concern at this point.

 

My 98 ls1 had a lifter tray crack causing the lifter to operate at 90 rotation, it led to severe grinding of the roller and after replacing everything including the oil I noticed lower pressure. I used to get 45- 50 psi on startup while cold and now I get 39. Idling hot I used to be at 36 Psi now I'm at 19. I think when these lifters and cams fail all that fine metal wears out all the mains and overall creates greater clearances anywhere the oil goes. Keep me posted on what the shop does because I am very concerned for my engine too and me and you had the similar failures.

 

I think we should stay in touch.

Sound like we have the exact same failure, and issue.

Thanks for the feedback.

The oil pressure is holding, but it sure isn't great.

 

Yeah mine is holding up as well, i left the old cam in there. Its an engine with 170k miles and i wasnt going to go on the mission of replacing the cam. Its amazing how tough the stock cam is. It chewed up half the roller on the lifter yet the cam lobe just lost the shine no major scaring or lobe damage.


[QUOTE=Clay_Assassin;1577619713]I think we should stay in touch.

Sound like we have the exact same failure, and issue.

Thanks for the feedback.

The oil pressure is holding, but it sure isn't great.[/QdUOTE]

 

I'm seeing about 19 psi now, hot, idle and summer heat type temps but with over 300k miles on the engine is not bad psi. I did have the top end apart at 274k miles to replace a failed lifter(s). I replaced all of the lifters, springs, rockers, pushrods, seals and had the heads checked out thoroughly. I did not replace the camshaft and the bottom end has not been apart. The minimum is 6 psi for the engine to run.

 

Interesting, what kind of failure did you have with the lifters? Did the roller fail and grind metal or did it collapse intrnally causing a misfine due to lack of actuation. Did you have any bent push rods or rockers that spit out the little internal rollers?

I want to brace myself for whats coming...i have 2 2001 tahoes with double the miles i got on the vette and no issues. From what ive observed its the same valve train.

 

In my case, it was a lifter(s) that was depressurizing when it cooled down therefore starting up, I got tapping that slowly over time, took longer and longer to go away. Then at the last, it tapped loudly...that was it...apart it came. I elected to replace all the things in the top end and valves were fine so there was no need. I did have brass guides put in.