57 trim CT turbo housing leaking air when pressure testing

[tekdeus]

Lately my car has had trouble boosting above 14.5 psi and sometimes only goes up to 10, and I have my AVCR set to 16.5 psi. So I rigged up the DIY boost leak test kit, hoping to find a simple leak somewhere and there was a lot of air coming from the back of the compressor housing where it appears to seal to the finned part. Most of the air was coming from a notch in the flanged part that I'm not sure if it is supposed to be there or if it is a chunk of metal that has been chipped off somehow(see 1st pic). When I tried to plug this leak with my finger, I also noticed some more air coming from the other side of the flange seal, and you can see the dark oil stained areas where it looks like air and oil have been leaking. I noticed quite a bit of shaft play, perhaps 1-2mm and the visible fins would almost touch the housing.

I'm assuming the compressor should be 100% airtight to the flange, right? Can the compressor housing come apart to allow this seal be serviced? Or is this thing about to go, and I should just replace the whole turbo? I've been told this turbo has a garrett center section. Would that make the oil line setup different? Thanks guys.

 

[nosman4]

There is an O-ring that seals the compressor housing and the backing plate of the housing. In your second picture you can see the snap ring that can be removed which allows that seal to be replaced. It sounds like your turbo is rather worn out though and you may be better off replacing it or having it rebuilt.

 

[Rennat]

that center housing is DEFINTALEY not a ct-26... so you may have to contact garrett about it, unless its a 'toyota ct-26' compressor housing...

 

[Poodles]

Looks like the custom turbo that one of the guys on ebay makes with a garrett center and stock housings.

Anyone that deals with garrett and the CT's should be able to fix/rebuild it.

 

[trydrew]

I had the same problem with a stocker that I bought "rebuilt" off of ebay. I made a pressure tester to test for boost leaks and it pointed me there. It was a bit unexpected, and I wasn't happy. So, I popped off the snap ring and it was missing the o-ring. :icon_mad: Lucky the one on my old CT was in relativly good condition.

With any luck, the o-ring you need will be the same size as a CT's ring. It'll make finding one a bit easier, if you choose to rebuild it.

Oh and the notch on the compressor housing is normally where a little dowel sits, which fits into a notch on the center cartridge iirc. It appears to be what keeps the CH clocked in the stock direction. If the o-ring isn't in place, the notch becomes a place for air to slip past the snap ring.

 

[suprafanatic]

fist off i have to say WOW YOUR CAR IS HOTTTT!!! OMG... second i would prolly replace the turbo if i were you, you have such a nice car maybe go with a non-ct turbo. there are some aftermarket turbos that bolt on to the stock manifold and exhaust, i just ordered a lipp boss turbo for my mkiii, its a direct bolt on. the ct turbos are just to limited and dont perform all that well.

 

[tekdeus]

There is an O-ring that seals the compressor housing and the backing plate of the housing. In your second picture you can see the snap ring that can be removed which allows that seal to be replaced. It sounds like your turbo is rather worn out though and you may be better off replacing it or having it rebuilt.

Is this O-ring easy to replace with the turbo in place? Just pop off the compressor housing? (This one is a CT-26 housing).

On the Dyno over a year ago, my A/F ratio was 10.5 at WOT (at the tailpipe). I installed a LC-1 wideband recently and it shows 11.5 across the range at WOT at the downpipe elbow. I would think that metered air slipping past this o-ring area would cause it to run rich...?

Yes, the idea of a better turbo is appealing but I'm really tired of dumping money into this car!

 

[MDCmotorsports]

Is this O-ring easy to replace with the turbo in place? Just pop off the compressor housing? (This one is a CT-26 housing).

On the Dyno over a year ago, my A/F ratio was 10.5 at WOT (at the tailpipe). I installed a LC-1 wideband recently and it shows 11.5 across the range at WOT at the downpipe elbow. I would think that metered air slipping past this o-ring area would cause it to run rich...?

Yes, the idea of a better turbo is appealing but I'm really tired of dumping money into this car!

Just make sure you don't smoke the fins of the compressor wheel and you'll be golden.

 

[tekdeus]

Looks like the custom turbo that one of the guys on ebay makes with a garrett center and stock housings.

Anyone that deals with garrett and the CT's should be able to fix/rebuild it.

I couldn't find anything on eBay. Do you know who I could contact? It looks like the CT housing was probably modifed to fit the finned flanged garrett back plate, so I'm assuming I'll need a garrett seal. I suppose silicone would be a bad idea?

 

[CajunKenny]

Contact Performance Techniques in San Bernardino, CA. Google them. My friend and I both had our turbos rebuilt by them. They charged me $475.00 with a two day turnaround. Ask for James.

Good luck!

And yes...your car is sweet looking!

 

[tekdeus]

I tried to remove the snap ring with a set of angled needle nose pliers, but it just keep slipping an popping back into place. Is there a proper tool to remove this huge snap ring? I gave up and reassembled everything. There is 1.5mm of shaft play (side to side, no in and out), and I can make the compressor fins touch the housing, so I'm not sure how long this turbo will last. I figure I'll just live with it until I can relpace the whole thing later.

 

[Rennat]

they make snap ring pliers... we bought some at a hardware store.

 

[suprafanatic]

ya if you have that much shaft play and its touching the walls, its done for, or very soon anyway.

 

[tekdeus]

A local supra owner said that my boosting issues could be caused by a weakened wastegate spring, and that if I shimmed it a bit, it might help it reach the boost my controller is set to. Worth a try?

 

[Rennat]

not with a possibly blown turbo... your just asking for failure.
you just spent all that money on the body work, and you cant get the turbo rebuilt????

 

[tekdeus]

After not having the car for 1.5 years for the bodywork, I'm keen to avoid any downtime at all!

I managed to get the compressor housing off with a huge pair of snap ring pliers and seal it up with high-temp silicone (what a nightmare job!). There was no O-ring as the two surfaces were machined to fit directly together without a seal. It is now 100% air tight, and there must have been a lot of metered air leaking out of there as my A/F ratio under boost used to be 11.5 and now it is between 12 and 13!! I now have to retune my car for pete's sake.

Was able to find a couple other small boost leaks, so the boost leak tester is a great thing to have.