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Discussion Starter · #1 ·
I went out to the garage today to get the Nova out since it's quite nice outside and I was going to give her a bath. Well I started the car up and everything was fine, I was letting her warm up and the oil pressure was right in the 40-60psi range. After it warmed up and I took her for a ride the oil pressure dropped at idle to around 5psi!!!! I checked for leaks and found none. I then took the valve covers off of both heads and everything had oil on it. I'm stumped on this one. I would think that 5psi at idle is way to low or am I wrong?
 

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5 psi at idle is a tad low. You should have about 10+ psi minimum. If you have a high mileage engine this is somewhat common, but it doesnt happen overnight. You can try a heavier weight oil- I usually recommend a 20w-50 for high mileage engines. What oil are you using now?
 

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Change the oil and filter, check the gauge for clogged line. Or even a bad gauge.

When you drain the oil cut the filter open look for metal shavings.

At 600 rpm the engine only needs 8 psi.

Is this that new engine???

Have you changed the oil yet?

Al
 

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Discussion Starter · #4 ·
Change the oil and filter, check the gauge for clogged line. Or even a bad gauge.

When you drain the oil cut the filter open look for metal shavings.

At 600 rpm the engine only needs 8 psi.

Is this that new engine???

Have you changed the oil yet?

Al
Yes, this is with the new GM Goodwrench crate motor. When I broke the camshaft in I changed the oil right after the break in. I drove the car for 50 miles, then changed the oil again, now I'm just using Valvoline VR-1 and an AC Delco filter for regular maintenance. the car idles at 750RPM and if I blip the throttle the pressure will go up with the RPM's. If I'm cruising at about 2,500 RPM my pressure is only at about 15-20psi.
 

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If you have a spare gauge try tapping into the block by the oil filter and check oil pressure to see if there is a difference.
 

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Sounds pretty normal to me. It's hard to tell the difference between 5 psi and 7 or 8 psi on my guage. I figure if it's over 0, we're in good shape lol!

Kev
 

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Discussion Starter · #7 ·
I had an extra Autometer oil pressure gauge so I just went out and hooked it up in place of the Autogage oil pressure gauge that was in there and it's a little bit over 5psi so I think I'm safe :D.
 

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that's kinda scary a new goodwrench engine only have 5 psi? I'd be calling the place where you got the engine and start asking questions. Read over your warranty carefully too. IMO hot oil pressure should be minimum 20 psi and cruising 35-50 psi.
 

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Discussion Starter · #9 ·
that's kinda scary a new goodwrench engine only have 5 psi? I'd be calling the place where you got the engine and start asking questions. Read over your warranty carefully too. IMO hot oil pressure should be minimum 20 psi and cruising 35-50 psi.
I already called them, I got the same answer from them, scoggin dickey, summit, and jegs. They all said that 8psi at idle is fine and not to worry.
 

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I already called them, I got the same answer from them, scoggin dickey, summit, and jegs. They all said that 8psi at idle is fine and not to worry.
pull the pan and make sure the pickup tube hasnt seperated from the pump as im sure gm didnt weld the pickup to the pump unless you did it already :yes: i also agree with big al " drain oil and cut open oil filter " just to make sure
 

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Wow, I never knew they were so low. I have a new engine and at idle its at 40 and at a full throttle 60. I would have freaked too looking at below 10psi. Now I know!!! Great place to learn.. JR.
 

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I have a hard time believing that is normal. Will a engine function with only 8 psi at idle... probably... But is that normal for a new crate engine? I have done a few of the GM crates.. I don't remember any of them idling at 5-8 psi when warm (with 10-W-30).
Tg
 

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i think we have a bad pressure valve in the oil pump.

Is till say, change the oil, cut the filter, look for foreign material.

Al
 

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5 psi for every 1000 rpm is what gm says,if the things idleing at 500 rpm with a hydrolic cam in it,i would just change the oil to something thicker and go do some burnouts..... :yes:
 

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Discussion Starter · #16 · (Edited)
Well, I drained the oil and it had a silver sheen to it. Took the filter off, cut it in half and low and behold metal shavings. I had a talk with Frank Pastrick Chevrolet and since my dad is good friends with the dealership owner he said that if I pull the short block out and bring it in he will will exchange the short block no questions. Looks like I have a project for this weekend...... I'll keep you all updated.
 

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if he is running synthetic he will lose pressure but gain lubricity..... i have a roller motor i warmed it up with conventional oil. oil pressure at idle was at 60 psi cold when warm it was at 40 switched to 10 w 30 lucas full synthetic and now when idleing warm its at 20 psi but as sone as i flex my right leg muscle it starts to climb up so long as oil pressure doesnt drop below 10 psi your good. thats why i recomended dropping the pan just to make sure the pickup tube hasnt come off the pick up. also if your using a high volume pump on a stock pan you may be sucking the pan dry which is bad i would recomend a deep sump pan of some type if your running a high volume pump :yes:
 

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if he is running synthetic he will lose pressure but gain lubricity..... i have a roller motor i warmed it up with conventional oil. oil pressure at idle was at 60 psi cold when warm it was at 40 switched to 10 w 30 lucas full synthetic and now when idleing warm its at 20 psi but as sone as i flex my right leg muscle it starts to climb up so long as oil pressure doesnt drop below 10 psi your good. thats why i recomended dropping the pan just to make sure the pickup tube hasnt come off the pick up. also if your using a high volume pump on a stock pan you may be sucking the pan dry which is bad i would recomend a deep sump pan of some type if your running a high volume pump :yes:
My ZZ4 did just the opposite. I held about 15 - 20 lbs running 10-40 conventional and 25 lbs running 10-30 Mobile One. I don't think he can run synthetics with the flat tappet cam though.
 

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My ZZ4 did just the opposite. I held about 15 - 20 lbs running 10-40 conventional and 25 lbs running 10-30 Mobile One. I don't think he can run synthetics with the flat tappet cam though.
yeah after i posted i went back and read his thread ooops flat tappet cams :no:
 

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5 psi for every 1000 rpm is what gm says,if the things idleing at 500 rpm with a hydrolic cam in it,i would just change the oil to something thicker and go do some burnouts..... :yes:
My local GM mechanic told me that 10 psi per 1,000 RPM was acceptable, so I guess its just who you ask.

However, I have purchased several crate motors over the years, and NONE recorded less than 20 psi at idle.
 
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