Engine/Transmission (1998.5 - 2002) HY Wastegate stuck shut

[NWhitney]

My HY35 wastegate is sticking shut and letting the truck build 30+ lbs of boost. Gets annoying when I have to down shift going up the hill to stop loosing speed and I have to let off or I will blow the intercooler boots off. I can get under the turbo and barley move the rod after the linkage is off. Can/Should I take the turbo off and remove the rear adapter to clean the soot out or is the bearing seized? I have a custom spring that would keep the boost around 27 lbs when the gate worked.

 

[AKAMAC]

The diaphragm assembly is probably bad (Hoslet #3594736).

You can pull it off by removing the 2 10mm nuts and cir-clip. Just twist and pull. Be sure to inspect the o-ring between the diaphragm tube and outlet.

If you like I can pay it forward off my old HY. Just let me know. Mike

 

[timbo]

I think you need to get new clamps or something! My clamps and boots are all stock and never blew one off, running 36psi ALOT!

 

[JJanetka]

Make sure it isn't just the wastegate itself and not the diaphram. You shouldn't be able to move the rod up into the diaphram without alot of force. Try putting a regulated amount of air (20 - 30psi) on it and check for movement. Thought the same thing on mine until I got it apart. after lubing the flapper shaft with syn. lube and working it around it frees up and is working again. good luck.

 

[therabbittree]

i second the actutor not the pivot point as the pivot is a bushing, no moving parts. The blowing intercooler boots off at 30-35psi is nut they should hold way way then that. like at LEAST double that psi... they should how 75 psi no problem... so some thing is wrong there. . clean the boot inside and out and the air horns too then use good t bolt clamps.....

Merry christmas,

Deo

 

[NWhitney]

Thanks guys I will pull the wastegate accuator off when I get time and see if it is bad. I have had the boots off a couple times and cleaned them up but they do not stay. I even did a little sled puller trick and put hair spray on the inside of the boots but that did not help. It is always the same boot and it blows if I get on it really hard really fast or downshift under load. I think if I can get the wategate working again it will help. Just hope I have not hurt too much with the spikes. Thanks again for the help.

 

[NWhitney]

Finally got the Wastegate apart tonight. Took the accuator off and tested it with some regulated air and it opens around 22 psi just like it should. The more air I add the longer it goes out just like it should. I got under the truck and checked and the flap that the E-clip is on will not move. No way no how!! So is it worth it to take the turbo off, try and clean the wastegate and put it back on or will I never get it to free up?

 

[SBall]

NWhitney,

I couldn't help but notice your thread regarding the stuck wastegate. I just had my truck into the dealer and he said that I too have a stuck wastegate which caused an excessive boost error code. They said they've had quite a few come with that problem, and their course of action is to remove the turbo and clean the waste gate. The dealer charge for this is $140. 00.



I didn't have them do the work yet as I am also dealing with a failing VP44. I thought I'd clean the wastegate myself while I tend to the injector pump. I'd be interested to hear what you find.

Steve

 

[JR2]

If you are capable of doing it your self then go for it. Pulling the turbo is not hard its just a PITA to get at the nuts on the bottom of the flange. Good luck and let us know how it turns out.

 

[SBall]

Hey Jr2,

You were right! The 15mm nuts on the bottom flange of the turbo housing were indeed a struggle to get off. Finally freed them up with some Gibbs and a metric box wrench. The rear-bottom was the hardest to get at because of the clearance issues. I then took the turbo/exhaust brake assembly down to the workbench to see what was wrong. The pivot arm bushing was frozen tight where the wastegate arm meets the actuator rod. Had to again resort to the Gibbs and a small gear-puller to separate the two. With the wastegate once again free to move and working properly, it should hopefully eliminate the overboost error codes.

Steve

 

[dieselshu]

The diaphragm assembly is probably bad (Hoslet #3594736).

You can pull it off by removing the 2 10mm nuts and cir-clip. Just twist and pull. Be sure to inspect the o-ring between the diaphragm tube and outlet.

If you like I can pay it forward off my old HY. Just let me know. Mike

You gotta a place that will sell the wastegate diaphragm?



Thanks

Dave

 

[JR2]

Hey Jr2,

You were right! The 15mm nuts on the bottom flange of the turbo housing were indeed a struggle to get off. Finally freed them up with some Gibbs and a metric box wrench. The rear-bottom was the hardest to get at because of the clearance issues. I then took the turbo/exhaust brake assembly down to the workbench to see what was wrong. The pivot arm bushing was frozen tight where the wastegate arm meets the actuator rod. Had to again resort to the Gibbs and a small gear-puller to separate the two. With the wastegate once again free to move and working properly, it should hopefully eliminate the overboost error codes.

Steve

That sounds about right, I ended up going to home depot and buying some cheap wrenches and making a couple of custom bend/cut's to get at it. The second time I did it I had to pull the exhaust manifold off with the turbo on it to get them loose. That is what i am going to do the third time too, its a little heavy but its sure easy.





John