How to tell if the turbo is not working

[Petersubaru]

Is there a way to tell if the turbo While still in the car is working properly...is there a way to check if the bearings are OK..if the turbo fails on the road, can it be by-passed some-how...Thanks

[MorganM]

With the engine off and cooled down a bit you can wiggle the prop shaft. Pull off the intake hose that goes to the intake side of your turbo charger. Stick your finger down the aluminum intake housing on the turbo and in the middle you will feel the end of the prop shaft for the turbo props. Giver her a wiggle wiggle !_! If its solid then your bearings are not shot. Also look for oil in there. Might be coming from the bearings. In some really bad cases I've seen where the turbo prop shaft is so loose that the prop rubs on the housing shaving off the prop and housing. Others I've seen just hosed and glazed with oil. Yet a minority of them show no oil leaking and the shaft is solid.

 

Get a real boost guage installed. That will tell you if you are atleast boosting and by how much. If you are boosting its working

 

I'm sure lots more suggestions will follow from more learned turbo folk so Ill just stop here

[archemitis]

yar, if it does break, like shaft in half. you can drive on your low compression motor, all day long, and the turbo will just act like a huge restriction. you can disconnect the little c clip on the wastegate actuator, so the exh. can get out easier.

 

if it just blows oil. your car can eat it but i think it can clog your cat after a while.

boost guages are great.

[subiemech85]

you should become familiar with "turbo whine", even at idle

[Dr. RX]

If the turbo fails, there is enough air and exhaust to flow around the turbine blades to allow the engine to run as a N/A, although at much less power since the engine has lower compression then a normal N/A engine. Oil blow by it cause by a bad seal, not the bearing, but a bad bearing will cause a seal to go bad. There are lots of things that can cause a turbo to not perform as it should, one big one is an exhaust leak before the turbo. This happens a lot on Subarus and is hard to see because most of the exhaust is sheilded. A boost guage is probably the best way to tell if the turbo is working while still on the car and engine is running.

[Dr. RX]

If the turbo fails, there is enough air and exhaust to flow around the turbine blades to allow the engine to run as a N/A, although at much less power since the engine has lower compression then a normal N/A engine. Oil blow by it cause by a bad seal, not the bearing, but a bad bearing will cause a seal to go bad. There are lots of things that can cause a turbo to not perform as it should, one big one is an exhaust leak before the turbo. This happens a lot on Subarus and is hard to see because most of the exhaust is sheilded. A boost guage is probably the best way to tell if the turbo is working while still on the car and engine is running.

[oddcomp]

i have a rx motor in my garage currently...

with almost no side to side wiggle

but yet has almost a half inch of in and out play on the turbo shaft..

and a nice puddle of oil in the bottom of the turbine housing..

 

i would bet its pretty well.. shot.. but it still made boost and only smoked a little