So my dual wastegates are ported on my series 5 turbo, yet the wastegate never seems to function, it's either running maximum boost 12+ psi , or running minimum boost of like 4 psi or so..the wastegate has worked a few times times and held 8-10 psi when it did actually work , which was about 5% of the time it's been boosted.

I noticed when I put the turbo on that the wastegate arm/flapper door had side to side play , id assume this is from wear and that's what's likely causing the problem...is there any way to fix it?

 

I have a turbo that does the same thing. I would assume you could mark the position of the arm in reference to the flapper door drill off the arm and pull out the flapper. Ream out the part of the turbine housing which it sits in and press in a custom made "sleeve" for the flapper and reassemble.
Then again a good condition turbo can be had for cheap.

 

Use compressed air on it and see what it does. Are you using any kind of boost controller?

 

No boost controller, the turbo is in good shape other than this problem.

The compressed air sounds like a good idea but the regulator to lower the pressure on my air compressor doesn't work, does that matter?

I really don't want to cut the arm off etc....and attempt to fix it..

I had a thought....maybe bending the actuator arm outwards will put the waste gate flapper in its proper position...idk ..it's a thought

 

I guess the Turbo is needing pulled to Fix the problem. I'm just gonna run low boost with my foot as the boost controller. I have rtek 1.7 wallbro 255 lph and 550/720 but my afrs are In the 12s , I'm gonna rewire the fuel pump and have it run constant 12v and check all my sensors.

 

I would give the actuator pressure and see how it is opening.

But most likely there is too much freeplay in the bushing and flapper door shaft. You don't need to drill it out or use a reamer. The factory turbo has a metal bushing in there that is tack welded. I just redid this with my turbo and there are a few pointers

Removal:
First get a good center punch and spot weld drill and drill out the wastegate pivot to wastegate shaft. Whatever the technical name is, I cant think of it, but you'll see the weld they use to assemple it. Remove the flapper door
Then you will see the tack welds they used to hold the sleeve in, Grind those off and the metal sleeve can be tapped out with a punch and hammer. It might be good to lube all this up as the first step.

Fabrication:
I did not make a stepped lip sleeve like stock, I just made a normal sleeve , but I had to mock up how far in it gets tapped in. I noticed the sleeve was not press fit from factory, just very tight clearance. If it was a press fit, it would only be maybe .001" over, I was able to tap mine in very easy. I gave it to my buddy with a lathe and had him machine the same od as the old sleeve. I also gave him my flapper door so he could machine a new tighter id and length for minimal thrust movement, tighter than stock.

Install:
tap the new sleeve in and put the flapper door on to see the best postion to cover the wastegate holes and tack the sleeve in. Tack the sleeve in with the flapper door in there so there is minimal warpage! I also used copper antisieze . do not tack so much that it will interfere with the pivot movement! I used a TIg welder and just fused the metals together without rod so I would not have clearance issues.
Last step is to mock up the actuator and pivot and decide where you would like to reweld the pivot arm back in place.

 

Thanks, that is basically what I meant but I never did it before. Great info

Sent from my Nexus 4 using RX7Club

 

I might just get a spare s5 hot side with no problems so I can swap it on or fix that one and swap it on, i want minimum downtime.

 

that would be your fastest fix. I work on a lot of bmw's and the newer twin turbos have a big wastegate rattle problem. Imagine having to buy a manifold/turbo setup that is welded together and doing the install on that. $2000 parts alone. Ting ting ting ting ting.

I should have did a complete turbo upgrade