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4thgenceli
10-11-2012, 03:53 AM
So my thoughts were confirmed today.

Backstory:
http://www.celicatech.com/forums/showthread.php?56328-Am-I-hitting-fuel-cut-on-my-gen4-3s-gte

Friday as I was driving home I started to do a controlled pull on the freeway (controlled as in I kept the boost at 10lbs). I went to shift to 4th gear and something popped (literally) and I had no boost after that. It felt/sounded like one of the couplers blew off again.

Anyway, long story short I drove boostless back home (god that thing felt so fucking slow). Pulled around back and parked it and started prepping for the new parts I'm putting on.

I checked the line from the compressor housing to the wastegate actuator. Good, sealed no cracks.

Line from the wastegate actuator to the vacuum pipes. That was also good without damage. The hoses to/from the canister on the back of the motor were in good shape and the line to the intake manifold and TVSV were find as well.

Disconnected the lines to the wastegate actuator. Hooked up some new hose to it. Capped the outlet and pumped air into the inlet. Just heard a whooshing noise. The diaphragm blew out.

So the question is...I need a new one. Any suggestions? Finding a stock St215 wastegate actuator is really a pain in the ass. I'm looking aftermarket, ideally something with interchangeable springs or a screw/nut adjustment. Two that come to mind are these:

TurboSmart
http://bit.ly/TyTTkZ


THM:
http://bit.ly/QXyoGL

MrWOT
10-11-2012, 05:16 AM
Whatever's clever. I'd make sure it has a threaded arm so you can adjust the length, otherwise installation could be interesting. You're not going to be swapping the springs after it's installed, totally extracurricular. I'd find one with a 7lbs spring and use a solenoid boost controller, so if need be you can cut it back and have a "limp" mode.

edit: on a side note, I'm amazed the diaphram ruptured. I see turbos all day long over 20 years old with 200k+ on them. I've seen exactly two turbos come through the door with blown actuators, and one were destroyed by the guy who removed it attempting to test with 100psi+ air source :rolleyes:

4thgenceli
10-11-2012, 06:01 PM
I can not confirm nor deny that someone blood related to me may or may not of 'tested' my wastegate actuator with an air compressor.

In hindsight, letting said person touch the car obviously has caused more grief than benefit.

Luni
10-11-2012, 06:59 PM
Tim, you really suck at this whole explaining thing.

Can you move your WG Actuator by hand? When you apply compressed air at it, does the rod move in and out? Is it secure?

Based on what YOUVE said, I dont think your problem is your WG actuator. The reason why is the actuator rod moves WITH pressure. If the diaphragm was shot and it was bleeding all the air off, youd actually overboost, unless the rod itself isnt attached to anything that would cause the WG flapper door to stay shut.

You understand what im saying?

4thgenceli
10-11-2012, 07:11 PM
I'll explain in more detail when I get to a computer. I'm failing to see your logic Luni.

What I think happened is the actuator failed (stuck shut for whatever reason) and now the diaphragm broke.

I'll update after I get my nuts fondled and ass probed.

Sent from my DROID BIONIC using Tapatalk 2

Hookecho
10-11-2012, 09:01 PM
Rob is right. Once boost pressure reaches 9lbs or so the pressure starts pushing against the diaphram and spring. That moves the arm outward opening the wastegate. So if you had a tear in the diaphram then the air would leak out and the wastegate would not open. Causing your turbo to overboost.

Maybe the wastegate itself is stuck open or the spring broke. That is why he wants to know if the actuator arm can be moved back and forth. If it can then the actuator is broke.

Luni
10-11-2012, 09:32 PM
Tim, you seem to not understand how the boost control system works.

If the wastegate actuator doesnt move, the car will OVERBOOST. If the actuator diaphragm wouldnt hold pressure, that means the spring the diaphragm pushes on would be constantly holding tension on the wastegate flapper door, and that would casue OVERBOOST. If the diaphragm was just bleeding off the boost that was entering it, instead of moving the rod out, it would OVERBOOST.

The only thing that could cause your car to NOT boost, would be the WG Actuator stuck OPEN, or the arm becoming disconnected from the flapper door (theres a little C-clip that holds it in there), or the turbine wheel shattering and physically not being there.

So, yeah, you NEED to check to see if that actuator rod is CONNECTED to the flapper door, and if you can, or cant pull that rod by hand if it is connected. If its connected, and you cant pull it by hand, that is NOT your problem.

4thgenceli
10-12-2012, 03:44 AM
Tim, you seem to not understand how the boost control system works.

If the wastegate actuator doesnt move, the car will OVERBOOST. If the actuator diaphragm wouldnt hold pressure, that means the spring the diaphragm pushes on would be constantly holding tension on the wastegate flapper door, and that would casue OVERBOOST. If the diaphragm was just bleeding off the boost that was entering it, instead of moving the rod out, it would OVERBOOST.

The only thing that could cause your car to NOT boost, would be the WG Actuator stuck OPEN, or the arm becoming disconnected from the flapper door (theres a little C-clip that holds it in there), or the turbine wheel shattering and physically not being there.

So, yeah, you NEED to check to see if that actuator rod is CONNECTED to the flapper door, and if you can, or cant pull that rod by hand if it is connected. If its connected, and you cant pull it by hand, that is NOT your problem.



Now that I sit back and look at it on paper and think logically with your explaination that all makes sense. One thing though, my overboosting issue I was experiencing (fuel cut, etc) very well could of been due to the wastegate actuator having some sort of problem (blown diaphram, etc). It was still (and still is) connected to the wastegate flapper door. If I put 10-15lbs to the wastegate, it doesn't move at all. This is disconnecting the outlet from the wastegate actuator, plugging it off and pumping it up with air. It doesn't build pressure, whatever I put in it just escapes from the can.


So everything is still pointing to the wastegate actuator as being the problem for the overboosting issue. However, I have another problem now (note the bold above). When I went out to check the wastegate actuator arm as you stated I started tugging and pulling and poking and prodding. On a whim I decided to see if I could spin the impeller from the intake side of the turbo. I pull the pipe and filter off. I reach in there and try to turn the blades to no avail. It's stuck worse than pulling factory exhaust manifold studs and nuts off a stock st162 that came out of New York that had no hood on it and was parked outside without cover. The screwdriver in my hand proceeded to fly across the yard. I retrieve said screwdriver and proceed to remove the compressor housing. Even more sadface is produced.

http://img.photobucket.com/albums/v488/celiman89/2012-10-11_14-35-35_885.jpg


http://img.photobucket.com/albums/v488/celiman89/2012-10-11_14-35-28_31.jpg


Something clearly happened, that impeller was NOT hitting the housing at all when I put it together. Clearly something gave out and now it's touching the housing. I couldn't feel any shaft play (horzontial or vertical play). Contiuning the investigation, I proceed to remove the catalytic converter/downpipe off to see if the turbine went boom. Once it's off I turn the unit upside down and shake it. Nothing falls out. I peek in and check out the turbine. It's all intact.

So where does that leave me? Well let's look at what I've discovered.

1. Wastegate actuator is acting and giving out all the indicators that it has failed.
2. Wastegate trap door works. The seal is not melted/bonded nor is the door stuck or have any sticky points.
3. Impeller does not rotate freely with the compressor housing on.
4. Impeller does not rotate freely with the compressor housing off.
5. If I put force to the impeller (wrap it with a towel and turn) I can get it to move.
6. A magnet dropped (and retrieved) from the intercooler returned no metal shavings or chunks of anything.
7. No oil in the intercooler (or coolant).
8. No burning oil or coolant out of the exhaust.

So take those 5 statements and what do you get? Easy. The turbo is toast. Why did it die? I have no fucking clue. Most likely a bearing gave out. If course without tearing it down to nothing I won't be able to find out 100% with certainity what it was. Am I going to go that far into it? I don't know. Most likely, but not for a long, long, long fucking time.

What am I gonna do? Well, all that I really can do is chock it up to something I did, blame myself and keep going.

I'm leaning toward a gen3 exhaust manifold with whatever turbo bolts right to that and hopefully it connects right to my downpipe. Chances are though it won't bolt to my downpipe and I'll need to get another one (but I've heard and read that the gen3 3sgte exhaust manifold bolts right to the gen4 3sgte manifold, which in turn the ct20b/ct26/whatever should bolt right to that and then hopefully I can connect the downpipe right to the turbo).


Is the SSAutochrome brand the one that is absolute shit? Should I steer clear of anything off ebay? A used exhaust manifold should be ok (providing it's not rusted to hell or has holes the size of my asshole in it) but should I get a new turbo? Rebuilt? Used?

Luni
10-12-2012, 04:27 AM
You should start by looking for another Gen4 turbo. If that don't pan out you want a gen3 manifold, a ct20b and an aftermarket gen3 downpipe. You may have to mod your exhaust for that I dunno. You could also run a twin entry 26 but that turbo does no performance on your engine so I'd stay away from it.

And I came to the same conclusion about the over boost problem. Leaky diaphragm equals over boost. And finally I'm honestly not sure what you could have done wrong to cause the failure. Just move forward with more knowledge of the whole thing. You now know pretty much how the boost control system works and understand what each part does.

Such is the fun/curse of owning a turbo car with a bunch of custom shit done to it.

Hookecho
10-12-2012, 04:33 AM
Was it getting oil?

4thgenceli
10-12-2012, 04:39 AM
Finding a 215 is basically impossible. I'll have better luck getting gen3 components. I'm still searching, hopefully I find something relatively quick.

I wonder if it could be oil or coolant choice.

Sent from my DROID BIONIC using Tapatalk 2

Tecker184
10-12-2012, 04:36 PM
I would get a gen3 exhaust manifold and a evo 8 or 9 turbo. The gen3 exhaust manifold can be found pretty cheap got mine for $50 shipped off mr2oc. The evo 8 turbo would be the easiest to find and cheap $250 range. The evo 9 turbo would be ideal supports 25psi and are relatively easy to find but pricey $350-500 range.

Of course putting an evo turbo on would involve custom coolant/oil lines, down pipe and flange adaptor. But i think that it's a good alternative that most people don't even think about.

I'm going to switch to an evo 9 turbo next year have the gen3 exhaust manifold already.

4thgenceli
10-12-2012, 04:59 PM
I would get a gen3 exhaust manifold and a evo 8 or 9 turbo. The gen3 exhaust manifold can be found pretty cheap got mine for $50 shipped off mr2oc. The evo 8 turbo would be the easiest to find and cheap $250 range. The evo 9 turbo would be ideal supports 25psi and are relatively easy to find but pricey $350-500 range.

Of course putting an evo turbo on would involve custom coolant/oil lines, down pipe and flange adaptor. But i think that it's a good alternative that most people don't even think about.

I'm going to switch to an evo 9 turbo next year have the gen3 exhaust manifold already.


If I go gen3 route I'll get the CT20b. They're (mostly) widely available and I can pick one up for around 400 used (hopefully). Manifolds are a dime a dozen, I should have no problem finding these.

ChrisD
10-12-2012, 06:15 PM
Shitty to hear dude. It happens.

Yeah I'd go with a gen 3 manifold and ct20b if I were you. I have no idea if it will line up to your downpipe. Worth a try, if not use it as an excuse to get rid of the cat.

Luni
10-12-2012, 09:20 PM
it wont line up

MrWOT
10-13-2012, 03:03 AM
The CHRA from a reg ct26 may fit those housings...?

4thgenceli
12-09-2012, 01:13 AM
I ended up buying a 215 turbo from SpeedRicer. Couldn't pass up on the deal. It arrived, I checked it out. Spins like butter. Not a hit of movement in the shaft at all (vertical or horizontal). Now here's why I am NOT a parts designer. It was a stupid 3" section of hose that caused every single problem. This hose went from the wastegate to the TVSV mess. It was in contact with something (maybe starter? something) where it was just rubbed from vibrations. It eventually made a hole and thus my boosting problems. I took the wastegate off and bench tested, it's just fine. Stupid hoses.

I took my time on reassembly though. I only have 6 leftover nuts & bolts. I ended up doing the other maintenance I needed on the front end also (including the wheel bearing that went out and was on the verge of total destruction).

MrWOT
12-09-2012, 01:50 AM
Glad its solved.

I lold... A little...

ChrisD
12-13-2012, 07:57 PM
I took my time on reassembly though. I only have 6 leftover nuts & bolts.

^LOL.