mkivbadger
Probationary Member
- 5
- 0
- Dec 2, 2002
-
Michigan
I'm reposting this here as I did not get any replys in the General Section - it probably should have been here in the first place.....
I searched and found a lot of good info, but nothing that has helped me solve my current DSM problem, so here goes....
My son and I were at the track doing a little test & tune when he discovered a serious oil leak & shut down. While he lost a lot of oil, he said that he still had oil pressure when he shut off. I initially suspected the problem was a blown front main seal, but after disassembly, I found that the oil pump was bad and had seriously galled the bearing surface in the front case (oblong hole).
I replaced the front case & associated seals, oil pump, water pump, etc., and on restart we experienced low oil pressure at idle. Our POS Autometer gauge shows 0 psi at 750-1000 rpm, and then jumps (as if it were sticking) to about 15-20 psi at about 1500 rpm. The oil pressure light comes on at idle (steady) and goes off as the revs increase. Going down the road, the autometer gauge shows oil pressure of approximately 45 psi at 2,500 rpm, and 60 psi at 3,000 rpm. With higher revs, Ive seen oil pressure over 80 psi.
I put in 20W-50 oil, and while better, we still have little to no oil pressure indicated at idle. I replaced the oil pressure switch, but still get the oil light at low rpm. Prior to the track incident, we would routinely see oil pressures > 100 psi on cold startup, and never got the oil light at idle. While the Autometer gauge is not the greatest quality, between the gauge and the oil light both saying the same thing, it seems to me like oil pressure at idle is in fact below the 11 psi stock level.
Questions:
Would changing the oil pump gears/impellers from straight cut (1g) to helical cut (post 93?) be causing this? It seems like oil pressure is OK (but not as high as pre-incident) at higher revs, but not OK at low revs. Do the newer design gears result in different pump characteristics? The helical gears are much quieter with less whine, but I thought that they had similar if not better performance than the straight cut?
While we dont THINK we wiped any bearings at the track, and the car now seems to run fine with no unusual noises or knocks, is it likely that the low oil pressure is in fact a result of a spun bearing(s)? What's the best way to check this? Wouldn't a spun bearing, BS or otherwise create quite a racket?
Any other ideas on things to check? Is it OK to drive?
TIA for your thoughts.
Mods:
95 Talon Tsi AWD, 1g swap, 16G EVO, 3 tb exhaust, manual bc, ACT 2600, DSM link, other stuff. Still have F&R balance shafts - and yes I know removing them would increase oil pressure, but that doesn't seem to directly address my current dilemma.
I searched and found a lot of good info, but nothing that has helped me solve my current DSM problem, so here goes....
My son and I were at the track doing a little test & tune when he discovered a serious oil leak & shut down. While he lost a lot of oil, he said that he still had oil pressure when he shut off. I initially suspected the problem was a blown front main seal, but after disassembly, I found that the oil pump was bad and had seriously galled the bearing surface in the front case (oblong hole).
I replaced the front case & associated seals, oil pump, water pump, etc., and on restart we experienced low oil pressure at idle. Our POS Autometer gauge shows 0 psi at 750-1000 rpm, and then jumps (as if it were sticking) to about 15-20 psi at about 1500 rpm. The oil pressure light comes on at idle (steady) and goes off as the revs increase. Going down the road, the autometer gauge shows oil pressure of approximately 45 psi at 2,500 rpm, and 60 psi at 3,000 rpm. With higher revs, Ive seen oil pressure over 80 psi.
I put in 20W-50 oil, and while better, we still have little to no oil pressure indicated at idle. I replaced the oil pressure switch, but still get the oil light at low rpm. Prior to the track incident, we would routinely see oil pressures > 100 psi on cold startup, and never got the oil light at idle. While the Autometer gauge is not the greatest quality, between the gauge and the oil light both saying the same thing, it seems to me like oil pressure at idle is in fact below the 11 psi stock level.
Questions:
Would changing the oil pump gears/impellers from straight cut (1g) to helical cut (post 93?) be causing this? It seems like oil pressure is OK (but not as high as pre-incident) at higher revs, but not OK at low revs. Do the newer design gears result in different pump characteristics? The helical gears are much quieter with less whine, but I thought that they had similar if not better performance than the straight cut?
While we dont THINK we wiped any bearings at the track, and the car now seems to run fine with no unusual noises or knocks, is it likely that the low oil pressure is in fact a result of a spun bearing(s)? What's the best way to check this? Wouldn't a spun bearing, BS or otherwise create quite a racket?
Any other ideas on things to check? Is it OK to drive?
TIA for your thoughts.
Mods:
95 Talon Tsi AWD, 1g swap, 16G EVO, 3 tb exhaust, manual bc, ACT 2600, DSM link, other stuff. Still have F&R balance shafts - and yes I know removing them would increase oil pressure, but that doesn't seem to directly address my current dilemma.
