I killed my turbo!

[GandalfS6]

While driving nicely on the highway, the turbo all of a sudden starts whistling loudly (I actually thought it was a police siren at first ). I took the turbo off this weekend and one of the impellers on the turbine wheel is broken off (see picture). I took the turbo to a turbo reconditionining specialist and this morning they phone to tell me that "something came through the engine and hit the turbine wheel".

I have already bought a Garrett T04E roller bearing turbo and I don't want the same to happen it! This probably means i need to open up the engine to see what hit the turbo? I will check the compression tonight but right now I am just depressed

What I want to know is has this happened to anybody else and what caused it? What could have hit the turbo?

[Honahon]

While driving nicely on the highway, the turbo all of a sudden starts whistling loudly (I actually thought it was a police siren at first ). I took the turbo off this weekend and one of the impellers on the turbine wheel is broken off (see picture). I took the turbo to a turbo reconditionining specialist and this morning they phone to tell me that "something came through the engine and hit the turbine wheel".

I have already bought a Garrett T04E roller bearing turbo and I don't want the same to happen it! This probably means i need to open up the engine to see what hit the turbo? I will check the compression tonight but right now I am just depressed

What I want to know is has this happened to anybody else and what caused it? What could have hit the turbo?

Sorry to hear that mate.

[Jay]

do you normally cain the car? if not it could be a piece of carbon???

Did the car run ok apart from the whistle??

Jay

[alg]

I could be wrong but I am not sure what can hit the turbo without some obvious sign.
I was led to believe that wear thru age led to imbalance in spinndle which leads to stress fractures of blades.
That is what it looks like. If something came through the engine it would cause more damage to more blades ???????

[Fat Audi 80]

I could be wrong but I am not sure what can hit the turbo without some obvious sign.
I was led to believe that wear thru age led to imbalance in spinndle which leads to stress fractures of blades.
That is what it looks like. If something came through the engine it would cause more damage to more blades ???????

That would make more sense to me. If that turbine is spinning at 10,000 rpm and some thing came through the Turbo, surely it would trash every blade on there??

Just my 2p's worth....

[GandalfS6]

Yep - all the blades were hurt but only only the one broke off. The bearing also went ( about 1mm of movement )probably as result of the imbalance when the blade went. The turbo had been smoking for a while so the seal was probably going as well.

[SteveH]

Could it be part of the turbo that has broken off and damaged the blades? When I had my RS2 turbo rebuilt it required a new hotside housing, due to cracks and a few large lumps where the casting had started to disintegrate. Perhaps you've had something similar and a piece of the housing has cracked off and gone through the blades.

[GandalfS6]

Could it be part of the turbo that has broken off and damaged the blades? When I had my RS2 turbo rebuilt it required a new hotside housing, due to cracks and a few large lumps where the casting had started to disintegrate. Perhaps you've had something similar and a piece of the housing has cracked off and gone through the blades.

I can check with the remanufacturers but the exhaust housing looked fine to me - there were a few scratches where I guess the broken impeller hit it but it didn't look cracked. If you are right I'll be very happy as the head stays on the car BTW, mine is a RS2 turbo as well.

[GandalfS6]

I just checked the compression and the readings are between 10.3 and 9.9 bar, so it seems fine. The plugs look like the car has been running slightly rich (we were busy remapping her) so no chance of detonation (especially running water injection and 102.6 octane).

I'm stumped as to what happened to the turbo!

[Doug_RS2]

(we were busy remapping her) so no chance of detonation (especially running water injection and 102.6 octane).

I'm stumped as to what happened to the turbo!

What EGTs were you running if you were remapping it at the time - sounds like you have stressed the turbo - either through surging, high EGTs or overspinning.

[GandalfS6]

What EGTs were you running if you were remapping it at the time - sounds like you have stressed the turbo - either through surging, high EGTs or overspinning.

Doug - I didn't check the EGT's but the AFR's were fine. We still needed to fine tune the fueling but Christmas holidays got in the way.

I am starting not to buy the "something hit the turbine wheel" story anymore. Wouldn't an impeller that shears off also hurt the other blades?

[GandalfS6]

Forgot to add - the previous tuner chipped the car with so many things wrong (including valve timing out by 15 degrees) and ran serious boost (1.9 bar). We were just getting all these problems sorted (including a few boost leaks) and running lower boost (1.7 bar). As a matter of fact, the car made 45 KW and 80 Nm more with a decent chip running less boost. But don't worry - we were only at approx 370 Hp which is acceptable for a chipped RS2.

Chances are really good that the turbo overspun with a boost leak running at 1.9 bar Or at least I hope so!

[GandalfS6]

OK I have my new turbo - more about that later!

I took the turbo to Geoff Mortimer, who overhauled the head when the woodruff key on the cam shaft sprocket went. He was the national rally champ in a Quattro!

He is also not sure what happened to the turbine wheel - a new pic below. He did suggest that rather than opening up the engine he get hold of a scope to see what is going on inside - I thought at one stage that the scopes that the orthopaedic surgeons use might work - never knew they acyually used it on cars! I does look like something hit the turbine wheel but maybe one of the impellers sheared off and caused the damage to the others

[GandalfS6]

New Turbo!

Below 2 pics of my new turbo. I use the car mostly for track days - so minimum lag is a priority for me. I would have preffered a Garrett GT3076R but I did not want to change the EM. We have therefore used a KKK K26 #6 (identical to the RS2 Turbo) Exhaust Housing matched with a Turbonetics single roller bearing and a T04E Super 46 trim compressor.

The turbo is good for around 420 hp (can run boost up to 2.5 bar but that will bend the conrods, I think) but should spool up quicker than the KKK RS2 turbo. I don't think turbo choices are quite an exact science, so we will have to see how it goes in real life. We can still make many changes to the compressor side if needed.

Here is the T04E compared to my now reconditioned RS2 turbo:

[GandalfS6]

.... and another one: