Help! Internal wastegate flapper is sticking!

[MarkIII4Me]

So I have a Turbonietics 62-1 Hi-Fi turbo. I noticed that the back of the WG flapper would get hung-up on the WG opening (preventing it from sealing shut) around 1 our of 5 times that I would open and close it. I spoke with the previous owner and he told me that he never had this problem.
It sucks because it took me quite a bit of time to get this thing mounted up in this first place. I have an older SupraSport Stage 3 trubo that uses the same hotside as the Turbonetics and this one has already had the flapper and arm rewelded, yet it still sticks every now and then as well. Just not as much.

How do I fix this flapper issue? I doubt it, but is there a way to fix it without unbolting the turbo from the exhaust manifold? What effect will this problematic flapper have on boost? My guess is increased lag.

 

[NTRA08]

Have you tried a little graphite?

 

[MarkIII4Me]

I read that high-temp lubricants are only a temporary solution and fail after a couple of weeks of carbon build-up.

 

[mdr40z]

my guess is combo of heat and deposits causing it, I'd take it apart, look at it closely and go from there

 

[MarkIII4Me]

my guess is combo of heat and deposits causing it, I'd take it apart, look at it closely and go from there

The turbo has low mileage on it and is clean. I haven't even ran it yet. I just bolted it up and used an air compressor hooked up to the wg actuator to push the flapper open and shut. After a couple of times, it began to stick. For all I know, once it warms up it won't happen.

 

[MK3Brent]

The turbo has low mileage on it and is clean. I haven't even ran it yet. I just bolted it up and used an air compressor hooked up to the wg actuator to push the flapper open and shut. After a couple of times, it began to stick. For all I know, once it warms up it won't happen.

That's true.
There will be a great deal of thermal expansion in these parts.

Where exactly on the seat is it "sticking?"

 

[IJ.]

Depending on the AR it usually only takes a mm or so to control boost, a static test can be misleading as they rarely open fully.

 

[MarkIII4Me]

That's true.
There will be a great deal of thermal expansion in these parts.

Where exactly on the seat is it "sticking?"

It appears that the flapper is pivoting and catching on the right hand side of the wastegate opening (right were it attaches to the bolt), when it closes. It's as if the flapper pivots too much and then jams on the WG opening when it closes. If I open and close it several times, it usually gets hung-up in the same spot. I have to keep opening it and closing it until it finally free's itself and closes all the way. Once it catches, the flapper leaves the wastegate open a couple of mm when it closes, but re-opens just fine. How bad is this? What effect will it have on boost. Fixes?

 

[MarkIII4Me]

I was thinking of filing down the the edge along the wastegate flapper if if it's decently larger than the wastegate hole, however, this may require removing the turbo. If I was to do that, I'd just disassemble the entire thing and fix this properly. This large turbo was a RPITA to put in and I'm not trying to do it again. I had to basically disassemble the thing and bolt it on in sections so the bolts were accessible. And they were barely accessible.

IJ has a point. Maybe the flapper won't even open wide enough to the point where it catched on the way down. But then again, if it does catch, then it may not swing wide enough to free itself either.

Who says to just hookup the downpipe and deal with it later if it starts to stick?

 

[gaboonviper85]

I personally wouldn't duck with the valve...instead I'd remove the material that it is catching on with a diegrinder! Put a nice polish in that area so it won't develop stress cracks and good to go!

 

[MarkIII4Me]

Crap! I don't think I'm going to be able to remove this turbo. There is next to no room to get a wrench in where the hotside meets the manifold adapter. I just realized that I was dumb enough to use locknuts on the studs instead of regular nuts with lock washers. I'm almost positive that when I try and remove the upper right nut, it will pull the stud up and pin itself against the exhaust housing.

What the hell was I thinking?!! :3d_frown:

I'll probably do the best I can to file down the flapper while the turbo is still mounted, (may be impossible), and reposition the wg actuator.

This sucks balls :nono: