big boost leak.

[jimsgsx]

In the picture here if you look at the back of the compressor housing you see a half moon cut-out on the edge. My car is leaking air like crazy out of it when boost leak testing and while driving i can only hit about 5 lbs. Of boost. I have absolutely no other leaks. Im pretty sure its the seals but just looking for advice and a affirmation. Thanks in advance guys. Its a 16g turbo on my 2g gsx.

 

[TunedUp]

There is an o-ring right there I would say it's bad. Oh and the c-clip there could be popped out of the groove. Just some thoughts.

 

[jimsgsx]

There is an o-ring right there I would say it's bad. Oh and the c-clip there could be popped out of the groove. Just some thoughts.

Yea i am gonna take er out and rebuild it. Either way its a good thing to do i believe.

 

[oneslowwdsm]

You may just have to tighten the V band that holds the housings together, if that is what you are talking about. It's also possible to bolt these down on an angle or just wrong so make sure you double check it's actually holding the housings together.

 

[2gmitsueclipse]

I am wondering if your wastegate is stuck open. I would test operation of the flapper and the actuator. The waste gate being stuck open would make it difficult to build boost.

What pressure are you testing is at?

Did you complete the test after being brought to operating temp, or cold?

Also, a little better detail your leaking area would be helpful.

 

[pauleyman]

Wastegate stuck open wouldnt cause the leak. I concur on compressor housing oring. Did this problem happen out of nowhere?

 

[2gmitsueclipse]

I may not be reading his description well enough. No a boost leak should not occur on the turbine side.

I see a half-moon shape on the waste gate opening.

 

[jimsgsx]

The half moon shape in the green circle is leaking air from under it. The clamp holding the turbo/hotside together is perfect and tight as heck. I did the boost leak test right after a 25 mile ride home from work. I did blt up to 15lbs and as soon as air is put in you can hear it pushing out from under that area i have circled. Was a pain in the ass to find that leak because who would think its coming from there right?

 

[jimsgsx]

And yes it just started doing this a week ago. Out of the blue.

 

[jimsgsx]

I am wondering if your wastegate is stuck open. I would test operation of the flapper and the actuator. The waste gate being stuck open would make it difficult to build boost.

What pressure are you testing is at?

Did you complete the test after being brought to operating temp, or cold?

Also, a little better detail your leaking area would be helpful.

My wastegate works perfectly. I checked that as soon as problem started. I am pretty thourough when investigating problems. By the book.

 

[jimsgsx]

You may just have to tighten the V band that holds the housings together, if that is what you are talking about. It's also possible to bolt these down on an angle or just wrong so make sure you double check it's actually holding the housings together.

I put a new 7cm hotside on months ago and its on there tight and perfectly.

 

[steve]

As others have said, it sounds like the compressor housing o-ring seal has failed.

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Make sure both the center section and compressor housing are clean and smooth where the o-ring will seat. It can't seal if the surfaces are a mess. Lube the seal so you don't cut it when assembling.

 

[jimsgsx]

As others have said, it sounds like the compressor housing o-ring seal has failed.

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Make sure both the center section and compressor housing are clean and smooth where the o-ring will seat. It can't seal if the surfaces are a mess. Lube the seal so you don't cut it when assembling.

Thanks Steve. Appreciate the good advice. This will be my first turbo rebuild but theres a excellent vid on youtube to follow.

 

[pauleyman]

Rebuild? All you have to do is remove the cover and replace the oring.

 

[Dsmkauai]

You just need a new oring for the cover. But if you choose to rebuild here's the kits I've always used, they come with the new oring.
http://gpopshop.com/products-page/mitsubishi-rebuild-kits/