low to no oil pressure after rebuild

50

Asked by Mar 25, 2013 at 10:24 AM about the 2001 Chevrolet Camaro

Question type: Maintenance & Repair

rebuilt. bearings /rods/ new oil pump/sensor/lifters/ every thing . starting oil pressure 60psi. after 30 min. warm up low to no pressure.  been back thru 3 times . same thing .. im missing something ..

9 Answers

50

2001 3.8 chevy/ buick k vin sorry

2 of 2 people found this helpful.
109,415

Did you have the block bored?

215

Bearing clearance might be out of spec, possible clog, oil not heavy enough, or there could be an internal oil leak early in the oil system that's temperature sensitive.

1 of 1 people found this helpful.
50

i installed cam bearing as you would a norm motor im thinking from reading others. hole is to big. some redrill smaller..oil is 5 w 30 bearings plastigauge good. oil relieve valve is good not sticking. new pump and gasket.

2 of 2 people found this helpful.
50

didnt bore block all was good no ridge. old bearings looked good for 100k

1 of 1 people found this helpful.
109,415

I take it had good oil pressure before the overhaul, so the problem is like Brian stated that there must be a oil pressure leak early in the oil system possibly one of the new parts goes into failure when it gets warmed up, oil pump could be sucking air on the intake tube or pump seal, that won't show until it reaches operational temp. The reason why I asked if the block had been bored is I had a engine bored out and they bored one cylinder off center ever so slightly and caused a hairline crack in the block, it ran good until it warmed up then the oil pressure went bye bye. Scratch one engine block.

1 of 1 people found this helpful.
104,645

As you probably know, oil pressure is a result of a resistance to oil pump output. The resistance comes from the main journals and the connecting rod bearings. Something has to be going on with them. Nothing else is changing enough when the engine warms up.

17,865

If you are doing another tear down, change the oil pump, and make sure it is one for your engine model. Make sure the bearings are not in backwards or upside down. Sound silly, but it has happened. I lost a 51 MGTD motor because of an incorrect spring rate in the outside oil pump. This is not your problem, but something simple that is overlooked or a wrong part is replaced can cause the issues. As others said, check cylinder pressure, check the bearing size, correctness and placement. To fix it, you may need a complete tear down and I'd rebuild with new bearing all around and oil pump. Air in the system or bearing failure that does not maintain pressure. Also check the sending unit, the line to the pressure gauge, and the gauge itself. I'd get an external reading on the pressure using test equipment before the tear down though and make sure it is not your send/sensing units. Good luck and have fun.

1 of 1 people found this helpful.
185

think its to much bearing clearance..the oil relief valve just lets oil flow thru filter and you can block it if you want all the oil to run thru the filter first but that wouldt explain it.. the engine gets hot and clearances expand ..pressure drops....im sure you set up the pickup... good luck

Your Answer

Camaro

Looking for a Used Camaro in your area?

CarGurus has 31,674 nationwide Camaro listings starting at $3,495.

ZIP:

Chevrolet Camaro Experts

  • #1
    dandyoun
    Reputation
    1,760
  • #2
    carGrrl
    Reputation
    1,220
  • #3
    Tom Demyan
    Reputation
    1,140
View All

Related Models For Sale

Used Ford Mustang
340 Great Deals out of 42,823 listings starting at $1,488
Used Chevrolet Corvette
122 Great Deals out of 16,194 listings starting at $3,995
Used Chevrolet Silverado 1500
2,811 Great Deals out of 158,487 listings starting at $1,000
Used Ford F-150
3,154 Great Deals out of 231,764 listings starting at $1,300
Used BMW 3 Series
1,154 Great Deals out of 34,386 listings starting at $1,000
Used Chevrolet Impala
507 Great Deals out of 32,641 listings starting at $1,000
Used Jeep Grand Cherokee
900 Great Deals out of 71,645 listings starting at $950
Used GMC Sierra 1500
1,176 Great Deals out of 62,310 listings starting at $1,995
Used Honda Accord
858 Great Deals out of 88,771 listings starting at $1,444
Used Jeep Wrangler
387 Great Deals out of 20,605 listings starting at $2,500
Used Pontiac Firebird
9 Great Deals out of 695 listings starting at $2,850

Used Cars For Sale

2018 Chevrolet Camaro For Sale
4 Great Deals out of 11,545 listings starting at $18,194
2017 Chevrolet Camaro For Sale
105 Great Deals out of 8,052 listings starting at $16,865
2016 Chevrolet Camaro For Sale
26 Great Deals out of 1,215 listings starting at $16,499
2015 Chevrolet Camaro For Sale
103 Great Deals out of 2,539 listings starting at $12,577
2014 Chevrolet Camaro For Sale
58 Great Deals out of 2,038 listings starting at $10,999

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.