Bad external wg??

[NeEmO6]

Ive had my tial 38mm external wg on for about 3 months now. Just recently i was hearing what sounded like a pretty big exhaust leak. I found the noise to be coming from the dump tube on the wastegate as if the wastegate was open . Yet the car does seem to be boosting fine and holding boost. What could be causing this? Is my tial going bad? For what its worth the wg is mounted on the o2 housing. And also im hearing like an intermitent rattling sound as if coming from inside the o2 housing, maybe the o2 housing gasket is broken or something?

 

[ZachM31]

it is a possibility that your gasket went to crap.. but first off, find out how it did that, did you replace it when you put your O2 housing back together? i think it is an $8 gasket or so..anyways, does it make the sound all the time? or just when you are boosting and the wastegate is open?

 

[NeEmO6]

The sound coming from the dump tube makes it all the time. The rattle sounds makes it every now and then when idling.

 

[99gst_racer]

Are you sure your dump tube isnt loose. I had a problem with burning up the supplied gaskets, and w/o a gasket, there would be a gap, and it would rattle. If it is where the dump tube meets the WG, then it will sound like ass when it opens. I've actually had both gaskets blow out, so the WG was loose on the manifold and the dumptube was loose on the WG.

 

[NeEmO6]

Are you sure your dump tube isnt loose. I had a problem with burning up the supplied gaskets, and w/o a gasket, there would be a gap, and it would rattle. If it is where the dump tube meets the WG, then it will sound like ass when it opens. I've actually had both gaskets blow out, so the WG was loose on the manifold and the dumptube was loose on the WG.

No, actually those gaskets have been replaced a few weeks ago and are not leaking. Its as if the wg itself is somewhat open all the time, because the pressure is coming out of the bottom of the dump tube just as when wg would be opening when full boost is reached. But it is doing this at idle.

 

[99gst_racer]

Just making sure, but you do have that Tial compression ring installed, right? Not having that installed would definitely cause the symptoms that you are describing.

 

[mirkoelek]

Just making sure, but you do have that Tial compression ring installed, right? Not having that installed would definitely cause the symptoms that you are describing.

I have that problem too, and you are right, without O gasket in the wastegate it would leak, but my O gasket doesnt wanna to go all the way in so i removed it and i got this leak. If its not all the way in it would leak between manifold and WG where i have SS gasket.... dont know what to do. Is there something wrong with the O gasket or WG itself or there is something that could be done to fix it. I believe that from heat it got deformed or something... any suggestions..
thanks

 

[99gst_racer]

I have that problem too, and you are right, without O gasket in the wastegate it would leak, but my O gasket doesnt wanna to go all the way in so i removed it and i got this leak. If its not all the way in it would leak between manifold and WG where i have SS gasket.... dont know what to do. Is there something wrong with the O gasket or WG itself or there is something that could be done to fix it. I believe that from heat it got deformed or something... any suggestions..
thanks

That metal o-ring is actually a seat for the valve. It must be installed. When set in, it does protrude fron the wastegate's flange, but when installed, the metal o-ring is pushed in flush with the flange surface and pressure is applied on the valve. That is what makes the valve seal.

It doesn't sound like anything is wrong, as far as I understand your discription. Install the metal o-ring, and as you tighten the wastegate down, the o-ring will be pushed in.

 

[mirkoelek]

That metal o-ring is actually a seat for the valve. It must be installed. When set in, it does protrude fron the wastegate's flange, but when installed, the metal o-ring is pushed in flush with the flange surface and pressure is applied on the valve. That is what makes the valve seal.

It doesn't sound like anything is wrong, as far as I understand your discription. Install the metal o-ring, and as you tighten the wastegate down, the o-ring will be pushed in.

ok, but i still have the leak there with the ss gasket from the AGP....

 

[99gst_racer]

ok, but i still have the leak there with the ss gasket from the AGP....

If the flange surfaces are flat, the gaskets are good, and the wastegate is tightened down enough to push the ring into the valve head, then it should seal.

If they are real Tial flanges, I find it hard to believe that they are warped, but it is worth looking into. If the flanges are flat and not warped, then it should be obvious why it's not sealing. You should be able to see where it's leaking from, and why.