From Dsmwiki
Turbo DSM owners often wonder about their turbo health. One common test is to check for turbo "shaft play".
The compressor and turbine wheels are connected by a shaft so that the two wheels spin as one unit. This shaft is free to spin via bearings between the shaft and the center section (the center section is the portion of the turbocharger between the turbine and compressor housings with the coolant and oil lines connected to it). If these bearings are worn or otherwise damaged, the shaft will be able to move too much (it will have too much shaft play). This can be tested pretty easily by checking the turbo shaft play.
To check for turbo shaft play, the car must be off, and the compressor must not be too hot (you'll be touching the compressor wheel and housing with your fingers). Remove the intake pipe or snorkel from the compressor inlet (center of the compressor housing) and move it out of the way so that you can reach inside the compressor inlet.
Reach inside the inlet and grab the nut that is at the center of the compressor wheel and make sure it spins freely. Next, try wiggling it and see if it wiggles. Wiggling it up/down (toward/away from the road) and side/side (toward/away from the front of the car) will have some play (the wheel will move in the housing a bit). This shouldn't be very much, but even a brand new turbo will have some play. It shouldn't hit the housing, though. Next, check for in/out (toward the driver's side then toward the passenger side). There should be no in/out shaft play. You won't be able to see what's going on. Go by feel.
If the wheel does not spin freely, or if there is too much side/side or up/down shaft play or any in/out shaft play, your turbo may be on its last leg. If side/side shaft play gets too large, the wheels may start to rub on the inside of the housing which will damage the wheel and the housing. If the bearings fail, the shaft can destroy the center section, the wheels can be destroyed, the housing can be significantly damaged, and the shaft can actually break. If you catch the problem before it gets so bad that you damage the compressor or turbine housings or the center section, you may be able to rebuild the turbo (replace the bearings and seals). Depending on the turbo, this might be cheaper than replacing it.
When you are finished with the test and everything checks out, remember to reattach the intake pipe to the compressor housing and tighten the clamp. If you disconnected anything else to do the test, remember to reconnect it.
Back to index
