CT26 turbo sounds almost like a compressor?! High pitch air flow sound when boosting!

[scotty]

Hey,

Firstly.. done a GE->GTE swap, just been driving a little, never had it going 100%

AFM was bad.. so changed it. With the old AFM it was drivable, and the last time I took it out for a short run the turbo started to make some noise.. no rattle or anything.. it actually sounds like a compressor?? It's got a high pitch air flow sound that gets louder/higher the more it's boosting.. It's a stock CT26.

What can be causing this??

Thanks

 

[MarkIII4Me]

Not sure how much help this is; but I've heard that sound before. I had the same thing happen to the original 7M that came with my car. It was ran with a BHG for years before I purchased it. The first day out I was boosting up an incline on the highway doing around 90mph. I remember distinctly hearing the turbo starting to make a high pitch whining noise that progressively got louder. Before I knew it my engine temp was in the red and there was black smoke billowing out the back of the car. As soon as I came to a stop the engine ceased-up for good. Perhaps the turbo became oil starved and the journal bearing was whining away from all the heat and friction.

Does your turbo have any leaks? Does it smoke? How much shaft play does it have? Do the fins touch the housing?

I'd make sure the oil lines are ran correctly to the turbo and it is recieving adequate pressure. An oil starved turbo is a dead one.

 

[Heavy D]

i get a high pitch sound when i give it a certain amount of throttle, but thats just the the turbo spooling up and whistles like those 18 wheelers

 

[scotty]

Not sure how much help this is; but I've heard that sound before. I had the same thing happen to the original 7M that came with my car. It was ran with a BHG for years before I purchased it. The first day out I was boosting up an incline on the highway doing around 90mph. I remember distinctly hearing the turbo starting to make a high pitch whining noise that progressively got louder. Before I knew it my engine temp was in the red and there was black smoke billowing out the back of the car. As soon as I came to a stop the engine ceased-up for good. Perhaps the turbo became oil starved and the journal bearing was whining away from all the heat and friction.

Does your turbo have any leaks? Does it smoke? How much shaft play does it have? Do the fins touch the housing?

I'd make sure the oil lines are ran correctly to the turbo and it is recieving adequate pressure. An oil starved turbo is a dead one.

Thanks for great reply!

I've driven with the turbo being like this for maybe 20-30 minutes, and the engine temperature and oil pressure has been excellent, no problems at all. The whining sound doesn't really affect performance, and I can't notice anything different from when it was fine.

It smokes just a little, but not much at all, normal I'd say.. I have no idea however how much shaft play it's got, how do I meassure/find that out? There are no oil leaks or anything.

 

[scotty]

Just went out for a run, pulled a error code 34 which is turbo... started a new thread about codes.. http://www.supramania.com/forums/sh...-and-52(knock-sensor)..&p=1572482#post1572482

 

[IwantMKIII]

uhm, it is a compressor....

 

[scotty]

I found out the problem.. I'll get a pic up shortly.. only hint I can give is that I need a new turbo..

---------- Post added at 08:46 PM ---------- Previous post was at 08:35 PM ----------

 

[IwantMKIII]

^yikes! didn't you check this turbo before you got it???

 

[scotty]

Yes. Have looked at the turbo-wheel(?) several times.. and just spoke to my brother, he said he checked the shaft play for about a week ago, and it was very minimum.

So got no idea how it happened.. it has to have been something with the turbo when I bought it.. oil pressure and everything else going to the turbo is fine.

 

[IwantMKIII]

^its a compressor wheel. Did that happen AFTER you bought it? If so, did you run without an air filter or something??

 

[scotty]

Yep, happened after I bought it. When I bought it the compressor wheel was in good condition, from what I could see anyway. Nope, never had it running without filter. Always had stock accordian hose and apexi filter..

 

[mobes]

Is your accordion hose falling apart, losing bits into the turbo?

 

[scotty]

Just had a look, accordion hose is in mint condition, nothing falling off or being loose etc..

 

[IwantMKIII]

Well, that doesn't just happen to a compressor wheel. SOMETHING was in the intake to do that kind of damage if there is no or little shaft play.

 

[scotty]

I've looked everywhere on the AFM housing, the air filter, accordion hose.. everything looks ok. The AFM housing has this mesh guard, so can't have come anything from the filter(?). The AFM housing it self looks perfectly normal, as well as the accordion hose. Does it have to have been something that has been sucked into the compressor wheel? I've also meassured shaft play now, it's about 2-3mm movement side to side.

 

[Flateric]

I am willing to bet that this damage was caused by something, who knows what, but something has collided with the fins. But something has without any doubt hit and damaged the fins. Check for hose break down, a forgotten washer, something. You may even find hints of what it was left in the intercooler on the inlet side if they, it, whatever it was didn't make it through the intercooler.

It could have been something really small that took out a fin or chipped a fin and caused that chip to damage other fins.

This really looks like collision damage to me from some foreign object striking the compressor wheel.

I would remove the intercooler and carefully tap, bump and try to dislodge anything that may be caught in the turbo/inlet side of it to see if you can get some clues about what went through your turbo.

 

[MarkIII4Me]

Did you make sure to prime the turbo properly prior to firing up the engine? If it was ran dry, even for a little bit, it can damage the bearing and cause shaftplay. Enough shaft play can cause the wheel to come in contact with the housing; which can lead to bent fins.

Not saying that's what happened. Just throwing that out there. Though your fins appear to have come in contact with some sort of projectile.

 

[Flateric]

I don't think the damage seen here was caused by shaft play due to the damaged portions being so far inwards from the fin tips. Unless of course a broken off tip then caused this damage after colliding and breaking off and then re-colliding with the other fins. Also the housing appears relatively unmarked for that amount of damage. I circled the chips I am referring to in red from the original image.

 

[scotty]

Another thing I just noticed by looking at the pic is that it seems like it's missing a bit on the compressor axle end, just to the right of the nut. I've just left the Supra and driven home, but I'll be back working on it this weekend, så I'll be sure to check it out then.

Thanks for lots of tips.. I'll try to check out if I can find anything in the intercooler..

 

[Flateric]

The bit of axel end is from the balancing process and totally normal.