NEED HELP - Oil pressure issues
Thread Starter
Drifting
Joined: Mar 2002
Posts: 1,298
Likes: 12
From: Salt Lake City UT
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.
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.
Burning Brakes
Joined: Apr 2006
Posts: 976
Likes: 1
From: Lincoln NE
Originally Posted by 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.
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.
if we assume for a moment the tester used was wrong...
and assume your sensors are correct... my question is after you broke the chain and went in looking for broken parts did you remove the oil pump? if so did you check the o-ring or replace it? no o-ring or a bad o-ring will bring your oil pressure way down to about what your describing. I dont' think you will damage anything at the pressure but of course no one wants that low of oil pressure if they can help it. If your able to get up to 83psi i wanna know how...
I have a ported LS6 pump and can't get over 60 when i take it into red. could be my sender but it seems ok.. idk.. this is a weird one.
Thread Starter
Drifting
Joined: Mar 2002
Posts: 1,298
Likes: 12
From: Salt Lake City UT
Oil pressure
The oil pressure checked at filter by GM is probably not the same pressure you would see at location of sender (top and back of block).
The actual owner of the engine shop put my engine together and specifically remembered the o ring and that the pickup tube slid into place properly and then was bolted in place. These guys have built my last 2 race engines and I have nothing but compliments on their work. I would not expect to see those high pressures at the filter if the o ring was misaligned etc.
Maybe a GM mechanic or engineer can tell me what difference in pressure you should see at filter then at location of sending unit.
The actual owner of the engine shop put my engine together and specifically remembered the o ring and that the pickup tube slid into place properly and then was bolted in place. These guys have built my last 2 race engines and I have nothing but compliments on their work. I would not expect to see those high pressures at the filter if the o ring was misaligned etc.
Maybe a GM mechanic or engineer can tell me what difference in pressure you should see at filter then at location of sending unit.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
I wouldn't think the pressure drop would be that great between the filter and the sending unit.
The service manual states that if the oil pressure readong at the filter is within specifications, inspect for an incorrect oil filter and/or malfuntioning oil bypass valve or a malfunctioning oil pressure gauge or sensor. Since the sensor is new that would likely rule that out. What filter are you running? Also, did they use assembly lube with moly in it?
The service manual states that if the oil pressure readong at the filter is within specifications, inspect for an incorrect oil filter and/or malfuntioning oil bypass valve or a malfunctioning oil pressure gauge or sensor. Since the sensor is new that would likely rule that out. What filter are you running? Also, did they use assembly lube with moly in it?
Burning Brakes
Joined: Apr 2006
Posts: 976
Likes: 1
From: Lincoln NE
well if you assume everything was assembled correctly then maybe there is something in the pick up tube causing problems.
when i did my cam swap i left to go pick up some food and let my buddy (who has swapped out oil pumps on ls1's before) install my new pump.. he forgot the o-ring and that gave me the same results your getting...
possibly a bad pump???????????
i'm outta ideas. good luck
when i did my cam swap i left to go pick up some food and let my buddy (who has swapped out oil pumps on ls1's before) install my new pump.. he forgot the o-ring and that gave me the same results your getting...
possibly a bad pump???????????
i'm outta ideas. good luck
Thread Starter
Drifting
Joined: Mar 2002
Posts: 1,298
Likes: 12
From: Salt Lake City UT
Oil Pressure
I thought that might be an issue before I went to GM as I originally had a K & N filter. I switched to a Mobil 1 and got the same results.
As they only replaced the chain and pump with a new SLP double chain and SLP hi Volume/pressure pump there should not have been any assembly lube etc. There was no indication in oil when I pulled the K & N filter of any substance in oil.
As they only replaced the chain and pump with a new SLP double chain and SLP hi Volume/pressure pump there should not have been any assembly lube etc. There was no indication in oil when I pulled the K & N filter of any substance in oil.
