NEED HELP - Oil pressure issues
NEED HELP - Oil pressure issues NEED HELP - Oil pressure issues
--------------------------------------------------------------------------------
Scenario:
2003 LS6 engine with less than 10,000 miles
At track broke timing chain at 5,000 rpm's
Tore engine apart and found one broken link, no damage to pump or associated front cover parts. Found 6 bent valves which were replaced. No bent pushrods or piston damage (a few small knicks). No material in pan and no discoloration of oil.
Replaced with SLP double roller chain and high volume pump.
Note: Oil pressure previous was approx. 30 lbs at idle and 50 lbs at 5,000 rpm's warm - (Mobil 1 10w30)
Started car after above and idle cold oil pressure was 18 lbs and at 2500 was 22 lbs. (Mobil 1 10w30)
Took car to GM to have them test pressure with special guage at filter - results:
idle - 52 psi
1000 rpm - 62 psi
2000 rpm - 65 psi
3000 rpm - 74 psi
4000 rpm - 83 psi
Based on above I replaced oil pressure sending unit. No change. After warming car up pressure still approx 18-20 lbs and only moved up to 22 lbs at 3500 rpm.
ANY SUGGESTIONS or RECOMMENDATIONS ?
Thanks,
J.R.
--------------------------------------------------------------------------------
Scenario:
2003 LS6 engine with less than 10,000 miles
At track broke timing chain at 5,000 rpm's
Tore engine apart and found one broken link, no damage to pump or associated front cover parts. Found 6 bent valves which were replaced. No bent pushrods or piston damage (a few small knicks). No material in pan and no discoloration of oil.
Replaced with SLP double roller chain and high volume pump.
Note: Oil pressure previous was approx. 30 lbs at idle and 50 lbs at 5,000 rpm's warm - (Mobil 1 10w30)
Started car after above and idle cold oil pressure was 18 lbs and at 2500 was 22 lbs. (Mobil 1 10w30)
Took car to GM to have them test pressure with special guage at filter - results:
idle - 52 psi
1000 rpm - 62 psi
2000 rpm - 65 psi
3000 rpm - 74 psi
4000 rpm - 83 psi
Based on above I replaced oil pressure sending unit. No change. After warming car up pressure still approx 18-20 lbs and only moved up to 22 lbs at 3500 rpm.
ANY SUGGESTIONS or RECOMMENDATIONS ?
Thanks,
J.R.
Did you use a new oil pump o-ring? Granted the car didn't have many miles on it, but I think that's one of the things you replace regardless of mileage. That's my opinion anyways...
If you did, did you make sure it was seated properly when it was installed? Even if it was new, if it was crimped or pinched when installed, it can result in low oil pressure.
Just an idea...
If you did, did you make sure it was seated properly when it was installed? Even if it was new, if it was crimped or pinched when installed, it can result in low oil pressure.
Just an idea...
Oil pressure Re: o ring
The engine (replaced timing chain and pump) was done by owner of engine shop. He said he specifically remembered seating o ring and sliding in pick up tube, then bolting down without issues. These guys have built my 2 previous race engines and I have been more than satisfied. This was a new o ring that came with SLP hi volume pump.
If o ring was not installed properly shouldn't I see less pressure than what GM tested at the filter ?
Would pressure at oil filter be greater than pressure at sending unit (top and rear of block) ?
The engine (replaced timing chain and pump) was done by owner of engine shop. He said he specifically remembered seating o ring and sliding in pick up tube, then bolting down without issues. These guys have built my 2 previous race engines and I have been more than satisfied. This was a new o ring that came with SLP hi volume pump.
If o ring was not installed properly shouldn't I see less pressure than what GM tested at the filter ?
Would pressure at oil filter be greater than pressure at sending unit (top and rear of block) ?
