Rittmeister
03-24-2009, 05:01 PM
Sigh. Forgive the long post, but I really need help.
Swapping from stock T25 to S15 bb T28, on a red-top S13 SR. Everything was beautiful with the T25 and stock fuel/air system.
Swapped to a T28 a few weeks ago. Sold to me by SPL - Swain-coated exhaust housing, Forge wastegate actuator, and HKS swiveling oil drain.
Installed PowerFC, Tomei 555 injectors, and Z32 MAF, all before the turbo, got it all running right. Everything was still beautiful.
Installed the turbo, with Taka lines, proper restrictor, etc; local tuner came over to do some street tuning. Everything still beautiful.
Went to the dyno to do some proper tuning. I'm pretty conservative; I had plans to set high boost at 15psi, low at 11 psi. Tuner (same guy) fiddled with things for a while, then on the first pull it went lean. Not enough to hurt but more than he wanted. While he made corrections we started to see blue smoke out the tailpipe, which did not cease. Things at this point were not beautiful.
We spend the next couple hours diagnosing. No smoke out the breather; no oil in coolant or coolant in oil; spark plugs look fine; compression is 150+ across the board; engine runs at the proper temp and has no trouble cooling off when the fans come on. We also found NO oil in the intercooler piping or BOV. Therefore we believe the engine to be healthy, and the turbo (used) to be the culprit. We checked shaft play, and one of the guys at the shop with lots of turbo experience pronounced it to be the problem.
I drove home (carefully) and ordered a new turbo. Took the old one off, and checked it out. There was no gooey residue in the exhaust housing which would indicate blown seals and too much oil burnage, and no evidence or rubbing/abrasion inside the housing which might make me think the bearins were gone and the wheel was rubbing the housing.
New turbo arrived yesterday. Brand new from Nismo Shop/West Covina. When comparing the shaft play on new and old, I couldn't tell a difference; my tuner came over and checked it out, and said he felt more on the used turbo.
Since neither was under any warranty (Nismo Shop sells it as a performance part, go figure) I decided to install the new one. I clocked it so the center housing was pointed the right way and the oil drain wouldn't hit the steering column and bolted everything up today. Everything is the same with two exceptions (other than the turbo) - on the advice of the tuner, I removed the breather hose from the intake to the valve cover, stuck a filter on the VC fitting pointing to the front, and capped the fitting on the intake. I also switched from the fancy HKS oil drain to the one from the T25, after slotting the holes to work with the T28. I did this against the chance that it was causing oil to pool and back up in the center section.
Fired it up and initially figured the problem was solved, but when water temp got to about 50*C and oil temps were in the mid 20s, I started to get blue smoke again. Not as much as with the old turbo at idle, but just as much when revving it. I haven't driven it yet.
I'm stumped. I've done a lot of searching here and elsewhere, and talked to a number of people. What could be my problem?
Swapping from stock T25 to S15 bb T28, on a red-top S13 SR. Everything was beautiful with the T25 and stock fuel/air system.
Swapped to a T28 a few weeks ago. Sold to me by SPL - Swain-coated exhaust housing, Forge wastegate actuator, and HKS swiveling oil drain.
Installed PowerFC, Tomei 555 injectors, and Z32 MAF, all before the turbo, got it all running right. Everything was still beautiful.
Installed the turbo, with Taka lines, proper restrictor, etc; local tuner came over to do some street tuning. Everything still beautiful.
Went to the dyno to do some proper tuning. I'm pretty conservative; I had plans to set high boost at 15psi, low at 11 psi. Tuner (same guy) fiddled with things for a while, then on the first pull it went lean. Not enough to hurt but more than he wanted. While he made corrections we started to see blue smoke out the tailpipe, which did not cease. Things at this point were not beautiful.
We spend the next couple hours diagnosing. No smoke out the breather; no oil in coolant or coolant in oil; spark plugs look fine; compression is 150+ across the board; engine runs at the proper temp and has no trouble cooling off when the fans come on. We also found NO oil in the intercooler piping or BOV. Therefore we believe the engine to be healthy, and the turbo (used) to be the culprit. We checked shaft play, and one of the guys at the shop with lots of turbo experience pronounced it to be the problem.
I drove home (carefully) and ordered a new turbo. Took the old one off, and checked it out. There was no gooey residue in the exhaust housing which would indicate blown seals and too much oil burnage, and no evidence or rubbing/abrasion inside the housing which might make me think the bearins were gone and the wheel was rubbing the housing.
New turbo arrived yesterday. Brand new from Nismo Shop/West Covina. When comparing the shaft play on new and old, I couldn't tell a difference; my tuner came over and checked it out, and said he felt more on the used turbo.
Since neither was under any warranty (Nismo Shop sells it as a performance part, go figure) I decided to install the new one. I clocked it so the center housing was pointed the right way and the oil drain wouldn't hit the steering column and bolted everything up today. Everything is the same with two exceptions (other than the turbo) - on the advice of the tuner, I removed the breather hose from the intake to the valve cover, stuck a filter on the VC fitting pointing to the front, and capped the fitting on the intake. I also switched from the fancy HKS oil drain to the one from the T25, after slotting the holes to work with the T28. I did this against the chance that it was causing oil to pool and back up in the center section.
Fired it up and initially figured the problem was solved, but when water temp got to about 50*C and oil temps were in the mid 20s, I started to get blue smoke again. Not as much as with the old turbo at idle, but just as much when revving it. I haven't driven it yet.
I'm stumped. I've done a lot of searching here and elsewhere, and talked to a number of people. What could be my problem?