Oil Pressure on First Start?
Oil Pressure on First Start? Fired up my new motor today for the first time and oil pressure was at 35 psi on the dash gauge. Stayed there for a while til we gave it a small blip in the throttle and went to 40 psi and stayed. Havnt driven it or revved it high any yet because its untuned but is this something I should be worried about?
I used some extra oil I had layin around just for start up to flush it out so it was half rotella and half 5-20 valvoline syn blend. Im going to change it tomorrow. Coolant temp was low obviously but when it warmed up the pressure didnt change. The pressure went to 40 only after throttle was applied but stayed there after. It was warmed up if that matters. Stock bottom end h/c ls1 90k on it.
Im going to try to find a mechanical gauge to put on it and after I change the oil Ill see if it will change any. Just weird that it would go to 40 after a throttle blip and stay but if I cut it off and start it up its mid 30s until throttles touched.
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Yea it's weird that it wouldn't come back down to mid 30's. I was going to ask if there could be anything wrong with the gauge or sender. If you have a mechanical one lying around, I would throw it on just to check. But 35psi hot is where my truck runs so don't think thats low.
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Joined: Aug 2004
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From: Auckland, Nth Is, New Zealand.
He's talking a brand new eng build, with a standed mellings pump for example he should be seeing 60psi cold 40+ hot
It also should'nt be staying a 40 with the blip of throttle and staying there...something 'IS' wrong
OK just read in later post it's a 90k eng...still not right with oil pressure doing what it's doing.
Yea it is. Not sure what pump he said it was replaced during the cam swap and it looked like it was new when I had the pan off so im not sure the brand. I asked if it was the tsp ls6 ported one and he said yea he thought it was. Could just be a oem replacement tho
What filter are you using?
After an initial start up on a re-build, oil & filter should be changed as there is rag lint and assembly lube that often builds up quickly in the filter. Wix/CarQuest, K&N or Hastings filter for a fresh start up, do not use a synth or synth blend for break in. Find a quality dino oil.
Do NOT use the Lucas additive, it's just 90 weight oil with soap-it'll foam up (air in oil) with is never good. This has been discussed everywhere.
If the problem persists or gets worse, I agree with the oil pump o-ring suggestion.
After an initial start up on a re-build, oil & filter should be changed as there is rag lint and assembly lube that often builds up quickly in the filter. Wix/CarQuest, K&N or Hastings filter for a fresh start up, do not use a synth or synth blend for break in. Find a quality dino oil.
Do NOT use the Lucas additive, it's just 90 weight oil with soap-it'll foam up (air in oil) with is never good. This has been discussed everywhere.
If the problem persists or gets worse, I agree with the oil pump o-ring suggestion.
I was using a cheap stp 3506...
Update:
So i hooked the mechanical oil pressure gauge up and the oil pressure was at 40 idle cold and hot and then i changed the oil with Mobil 5-30 and a Ac Delco filter.
Fired it up and it was about 36-40 at cold idle and hot. One thing I did notice was the oil gauge in the car was accurate when the car was at idle but didnt move when I revved it up. On the mechanical gauge when I revved it up it read up to about 60 hot.
So is there still something I should be worried about or should I just let it be and watch it?
Update:
So i hooked the mechanical oil pressure gauge up and the oil pressure was at 40 idle cold and hot and then i changed the oil with Mobil 5-30 and a Ac Delco filter.
Fired it up and it was about 36-40 at cold idle and hot. One thing I did notice was the oil gauge in the car was accurate when the car was at idle but didnt move when I revved it up. On the mechanical gauge when I revved it up it read up to about 60 hot.
So is there still something I should be worried about or should I just let it be and watch it?
Sounds like you're OK. I'd believe the accuracy of a aftermarket mechanical gauge before a stock gauge. Perhaps the stock sending unit needs replacement.
What vehicle are we talking about?
What vehicle are we talking about?