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Flapper on exhaust side of turbo stuck open

Tell me if anyone has ran across this problem. The other day I got into full boost and afterward noticed the exhaust sounded like it had a massive leak. Got it home and checked the downpipe gasket and while down there realized the exhaust was coming from my o2 dump. Next morning I went ahead and pulled the wastegate actuator off and checked the flapper. The rod it's connected to actually slides out a bit. Didn't think much of it at the time and sprayed everything with wd40 and called it a day. Fixed the issue and thought it was smooth sailing. Well yesterday I got the 3" turbo back installed and I wanted to see if there was a difference in power. This time while in boost it felt sluggish up top. and once again the o2 dump was screaming. So picked up a new exhaust housing from Geno and went to work last night. One thing that struck me odd though was the fact that the flapper arm is sliding outward away from the housing. Both exhaust housings I got from Geno are solid in that direction and only flip up or down.

Here's a video of what I mean.
click

In the vid you can see how the flapper goes off center of the hole and is very hard to flip side to side
 

Muskrat

Well-known member
Joined
Jun 13, 2004
Messages
2,107
Location
Lexington, KY
I'm guessing you want to know why the flapper got stuck? (wasn't really clear in the post)

I'd say just examine it vs the good one you have and you should be able to figure it out. Something wore out/broke that retains the flapper it sounds like. Try and figure out how it was put assembled. That will give you a clue.
 

Yeah, that's the plan. Just the downpipe is fighting with me so I'm going to have to wait for a second hand to get it out. I'm wondering if it's repairable. If it is, i'd like to keep it since it's the 16g hotside
 

BluFalcon

Well-known member
Joined
Jan 20, 2002
Messages
1,312
Location
Wichita, KS
Looks like a Taiwan exhaust housing. The flapper arm is supposed to be centered so that the flapper door closes over the wastegate port. This is accomplished on the factory MHI and Taiwan style housing by a friction fit bushing that keeps the flapper valve and arm centered in the correct position. From what i can see in the video, it looks like the bushing is loose causing the arm to hang open. You might be able to pull the housing off the car and have the bushing tack welded into place to keep it from moving around.
 
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