The car was assembled and tuned back in April/May of 2013. The turbo was a brand new EF3 rebuild using my stock IX turbo. Everything has been fine for 6 months but I went to the track Friday night and now there is a weird rattle from the wastegate flapper or arm attachment. I verified this with a stethoscope on the o2 housing and arm, but also at idle there is air coming out of the wastegate dumptube.

The first thing I checked were the nuts on the wastegate arm and they were not loose. The noise basically sounds like the wastegate flapper is barely bouncing against the seat in the housing at idle. The weird part is that the sound goes away after driving and heating the car up.

I have also noticed lately that boost seems to be lazy and I used to hit 31psi but now I only get 28psi. I attributed this first to weather but with this issue now it seems like maybe the flapper isn't seated all the way.

When I originally built the car I changed the preload that comes on the EF3 to what was suggested on these stock frame turbos (I believe 1.5 turns?).

Short story long, I'm looking for ideas of what has gone wrong before I tear the whole setup apart and would appreciate any ideas

thanks,

 

I had this problem on a car. The rivet type of thing that holds the flappers onto the arm got loose, causing the noise. It also caused lazy spool as any amount of exhaust pressure would push the flapper to one side and allow exhaust to escape.

You may be able to get away with welding the flappers to the arm. If not replace the housing.

 

replace the entire turbine housing? I hope that's not the case cause it was a brand new MAP housing when I did the rebuild. Car has less than 5k miles on the turbo

 

What actuator is fitted to your turbo? Is it a stock M.H.I. IX actuator, or a MAP/Turbosmart WGA?

 

No warranty?

Whichever way, take off the turbine housing and see what's going o.

 

Yeah it's the turbosmart wastegate. I'm in the process of tearing it apart right now so I'll know shortly and contact the manufacturer tomorrow

I'm removing ac while I'm at it and getting my manifold ceramic coated

 

here's a video of the wastegate flapper rattling which is the noise I heard. I'll contact my turbo manufacturer in the morning to see what my options are. Seems like it can be welded to cut out the slack but I don't want to touch the housing until they say so

https://www.facebook.com/photo.php?v...47918885363108

 

You are in the process of tearing what apart? I don't think that there is a need to tear anything apart.

Look I will be honest with you: MAP doesn't actually manufacture the turbine housing, or the flapper valve, or even the wastegate actuator. Turbosmart makes the actuator. MHI casts the housing and fabricates the flapper valve assembly.

MAP has nothing to do with it. MAP has a lathe or mill that cuts the MHI housing internally to fit the diameters of their turbine wheel. But, when your housing goes through their machine shop no one touches the flapper valve assembly.

All you really have to do to cure the rattle is adjust the actuator in order to increase spring pressure. That is probably all you need to do. At least I am 90% certain that is the source of your problem. There is no need to go and tear everything apart though.

 

Tensioning the actuator is not likely to solve the problem. In the case I experienced it made the problem worse because the extra tension just forced the flapper to sit at an angle on the seat, leaving the wastegate ports partially open. This made spool up even worse. It could only make 10 psi at 5000 rpm (stock turbo).

 

So I contacted MAP (great customer service by the way) and everything seems fine. The metals expanded differently and loosened up a but so I can simply add more preload to the flapper actuator and tighten it up like it was from the factory. I sent them a video just so he can be sure before I reinstall everything, but from the information he gave me it seems like everything is still okay and nothing is bent or broken

here's a good video of the flapper though. When I put pressure on it and close the valve it still seats perfectly and doesn't move or rattle. Easy fix

http://s83.photobucket.com/user/ILuv...233f4.mp4.html

 

I decided to remove A/C which is something I've been wanting to do forever, and I'm going to have my manifold ceramic coated and get a turbo blanket so although I didn't need to tear everything apart, it was something I planned on doing eventually anyways.

 

I like your valve cover.

 

Yeah MAP is right! All the bits and pieces of dissimilar metals and other various materials, meshing with differing tolerances, that assembled together comprise the internal WG assembly as a whole on your new MAP turbo(i.e. WGA spring and rubber diaphragm, flapper valve, flapper shaft, machined and hardened seat, as well as the the actuator rod itself with its threaded turnbuckle tip and etc. All may spec out at a certain PSI when originally tightened as brand new.

But, this collection of dissimilar brand new pieces tends to stretch and comply and take a particular set after repeated work cycles. Just as the studs on a cylinder head need to be retorqued. Or your new eyeglass frames need to be retweaked by your optician after you wear them for the first few days.

Specifically, and for these very reasons, all 16G wastegate actuators are adjustable in the first place with a threaded tip which allows for tightening after the actuator's internal spring takes its initial set. Since everything changes a bit and settles in...for that specific reason wastegate actuators are threaded and adjustable. Everything changes. Even solid granite is eventually altered over the course of time by wind and rain.

 

Why would you want to remove the AC? I never understood why people do this on a street car. No AC sucks in the winter for defrost and sucks in the summer for obvious reasons.

 

I only drive the car when I feel like it, so if the weather is not up to par I don't drive the car. It's a weekend car, no need for A/C since I never use it