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Old 05-26-2012, 04:36 PM   #1
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Default Internal Wastegate Sticking Open

The internal wastegate on my disco potato is occasionally sticking open.

Its exactly like this guy's:

except it only happens occasionally and it isnt a chinaturbo, its a Garrett.

After pulling the DP and inspecting, it appears its doing exactly what Corky describes in his WG porting guide as a possible problem created by over-porting the wastegate:

Quote:
Note that the wastegate valve (flapper door) can move around quite a bit. This freedom of motion causes a problem with enlarging the port. The hole cannot be uniformly larger as the free motion of the valve can cause the edge of the valve closest to the pivot arm to collide with the edge of the hole and jam it open.
Except I don't believe my wastegate is ported (I'm the 3rd owner of this turbo, so I can't be sure)

How can I solve this problem?

My first thought was that if I could make the flapper not quite so loose on the arm, it would solve the problem... maybe putting a circlip or safety wire around the shaft that connects it to the arm to take up some of the slack? Not sure if either of these would survive in there though.

Last edited by Handy Man; 05-26-2012 at 04:49 PM.
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Old 05-28-2012, 04:21 PM   #2
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Anything? anyone? am I totally screwed and going to need a new turbine housing?
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Old 05-28-2012, 06:25 PM   #3
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Add a helper spring to help close it?
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Old 05-28-2012, 06:45 PM   #4
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Thanks, but the amount of closing force isn't the problem. When it catches on the lip, no amount of force will get it to close, you have to jiggle it or open it and close it again.
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Old 05-28-2012, 06:49 PM   #5
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I see, video didn't show up the first time. Reducing the slack between the flapper and the arm it is on should help. I assume the play between them is there for a reason? (ie, not welding the flapper solid to the arm).

Or try some inconel wire to reduce the play.
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Old 05-28-2012, 10:54 PM   #6
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I definitely never ported it Will and if you PM Codystrife you can ask if he ever did as he was the original owner of the turbo kit.
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Old 05-29-2012, 01:09 AM   #7
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Port it or get a flapper from another turbo.
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Old 05-29-2012, 09:56 AM   #8
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find the post from levnubhin about adding a circlip to the back of his flapper.
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Old 05-29-2012, 10:33 AM   #9
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Quote:
Originally Posted by paNX2K&SE-R View Post
I definitely never ported it Will and if you PM Codystrife you can ask if he ever did as he was the original owner of the turbo kit.
Thanks! That helps.

Quote:
find the post from levnubhin about adding a circlip to the back of his flapper.
I was about 5 minutes from giving that a try. Found his post here. Its good to know it worked for him, I'll give it a shot. Thanks!

If it doesn't last, I'll try some inconel wire, I didn't even know they made the stuff, but I'm sure it could handle the heat.
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Old 05-29-2012, 10:37 AM   #10
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oh lol, the first video you posted WAS levnubhin's. (btw i fixed the videos in his posts)
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