two years ago i replaced the engine in my 99 suburban with a rebuilt jasper classs 1 engine. Since i put it in my oil pressure is low. It sits hot idle at 15 psi and running at 35. i know this is considered good oil pressure but i have owned 4 new chevys and they all idle at 20 to 25 psi when hot. Any idea why this would be. all my trucks have over 180000 miles on them and still have better oil pressure then this "new engine". The class one engine is supposed to have a higher torque cam in it. i have the Diff out now for repair and im replacing the oil cooler lines and was wondering if this pressure problem could have something to do with the oil adapter bypass or something. The engine is supposed to have a new oil pump in it. The old engine also had low oil pressure but it may have been real as i spun a bearing. I have replaced the sending unit and checked it with a mechanical gauge.
new jasper 5.7, low oil pressure
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did you replace the oil cooler, or at least completely clean out the oil cooler when you replaced the engine?
i know with ford if there was any metal damage, we are supposed to replace the cooler and in some cases the intake manifold when replacing the engine due to metal contamination.
Wow! Not replacing the oil cooler was a very bad move. Once metal gets into it you can't remove it but it will slowly work it's way through and contaminate the new engine.
Are you using an accurate oil pressure guage or the stock dash one? The dash guages are very inacurate.
Are you using an accurate oil pressure guage or the stock dash one? The dash guages are very inacurate.
Assuming the oil cooler was clean no problem....if the previous engine had catastrophic failure that is another story.
If the last engine was just worn then you might be OK. But I agree that it still should have been cleaned. Same with automatic transmissions lines.
I should add have you talked to Jasper about your concerns?
If the last engine was just worn then you might be OK. But I agree that it still should have been cleaned. Same with automatic transmissions lines.
I should add have you talked to Jasper about your concerns?
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Well it looks like i blundered with not changing the old oil cooler because the engine did spin a connecting rod bearing so im sure there were some contaminates in the oil. Would it really be enought to cause instant wear like that. Would it benefit me to change the oil cooler now as i have to change the lines becuase they are leaking? I did talk to jasper and they keep going back to GM engines are not out of spec untill 4 psi. Could it just be the different cam that they put in for the higher torque?. Some notes about the truck. I noticed slowly a clunking in the engine when it was cold,then it just kept getting worse and worse. i stopped driving it there as to not have major failure. Once i dropped the oil pan i could feel the slop in the connecting rod. At this time i just ordered an engine. The crank definatly had some wear on it. Wouldnt these particles get caught in the oil filter being it was a slow and steady wear?
Is the oil pressure different after 2 years?
Expect a minor change to lower pressure.
But a GOOD gauge is important.
Who knows what a factory one really is reading?
Expect a minor change to lower pressure.
But a GOOD gauge is important.
Who knows what a factory one really is reading?
1. filter would prevent major chunks left in cooler from harming engine, except for:
2. the new oil pump could be damaged, unless chevy changed their designs since I was last in one, b/c the oil pump is upstream of the filter.
BUT, I don't think this is in reality the/a problem. Biggest question, as previously posted, is "Is the oil pressure different after 2 years?"
M
2. the new oil pump could be damaged, unless chevy changed their designs since I was last in one, b/c the oil pump is upstream of the filter.
BUT, I don't think this is in reality the/a problem. Biggest question, as previously posted, is "Is the oil pressure different after 2 years?"
M
I had a co-worker that bought a new Chevy pick up ('07).
Had a bad oil pump from the factory.
Toasted the motor within 1500 miles.
Got a new motor, then traded it off.
Had a bad oil pump from the factory.
Toasted the motor within 1500 miles.
Got a new motor, then traded it off.
Originally Posted By: jstutz
Guys, the oil pressure has not got worse at all. The truck probably has 15k on in since the engine has been put in. No change at all. Runs exactly as it did from day one.
What is the weight of the oil you are using, and do you know what weight oil they told you too use.
Guys, the oil pressure has not got worse at all. The truck probably has 15k on in since the engine has been put in. No change at all. Runs exactly as it did from day one.
What is the weight of the oil you are using, and do you know what weight oil they told you too use.
If you are worried cut a filter apart the next oil change. I would not worry too much over it. The filter probably caught most of the junk.
Other people with Jasper engines might have the same exact pressure you do......
I would just keep track of the pressure and cut a filter apart every once in awhile.
Other people with Jasper engines might have the same exact pressure you do......
I would just keep track of the pressure and cut a filter apart every once in awhile.
Just a update, took the oil cooler hoses off today to replace them as they are seeping. i blew thou the hose and felt very little restriction if any at all. I did come across another question though. I pulled the oil filter adapter off to replace the seals while it is apart. there are two little pressure spring seals. one is behind the filter and one is beside the filter. What are these for. They are very easy to push in. Are they supposed to be. If not if the spring was weak from being old would it allow oil to pass unrestricted resulting in low OP.
If your adaptor is like mine was, those valve are closed when the oil is cold and they open when the oil gets hot.
Might be??
Might be??
Originally Posted By: jstutz
Well it looks like i blundered with not changing the old oil cooler because the engine did spin a connecting rod bearing
Don't bother with replacing the oil cooler or trying to clean it.
You can't clean them and replacing it is not cost effective. If you ever need to replace the cooler your better off to just buy a complete radiator. That way You get all new stuff and a warranty.
Well it looks like i blundered with not changing the old oil cooler because the engine did spin a connecting rod bearing
Don't bother with replacing the oil cooler or trying to clean it.
You can't clean them and replacing it is not cost effective. If you ever need to replace the cooler your better off to just buy a complete radiator. That way You get all new stuff and a warranty.
Replacing the cooler now is like closing the barn door after the horses got out. According to Jasper the OP is acceptable, hopefully there was no junk in the cooler transfered to the new engine. Other than that I'd say drive it and enjoy it. If you have a problem in the future remember to change the oil cooler if you swing an engine.
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If this pressure is in line with what it was when you installed it ..what's the worry? Even if the cooler was chuck full of garbage, the engine obviously didn't seem to show anything in terms of degradation. I see nothing in your original post about it "getting lower" ..but merely that you didn't like it as it came from Jasper.
If you had true low oil pressure, at least the nasty type, your lifters would be clacking away. If they aren't, then you've got adequate volume at pressure.
If you had true low oil pressure, at least the nasty type, your lifters would be clacking away. If they aren't, then you've got adequate volume at pressure.
yep, pressure is exactly where it was when i installed it. i just thought that for a 2500 dollar rebuild, the oil pressure would be at factory spec level. Engine runs great, no noise. Usually i refer to lower oil pressure with wear. No big deal i guess. I just thought it was odd that my other two trucks with over 200k miles on them have better oil pressure than my new one.
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