Turbo outlet boot leaking.

[gymcarm]

O.K. I got the FSD installed and everything works well. I am getting a very annoying squeal from the rubber boot between the turbo outlet and the intake manifold. I tried for 3 hours last night to get it to seal. It is fine at idle. Only leaks when the engine is run up to ~2500 rpm with no load. (it also leaks while driving) I found the leak with soap bubbles.

What's the trick to getting this thing to seal? I tried the search feature and found nothing related to this. Makes me feel like I'm missing something obvious.

[More Power]

It is somewhat normal for an oily buildup to occur on or near the turbo due to very slight leaks.

The best way reduce those sorts of leaks is to buy a new rubber hose that connect the turbo to the plenum, then use a solvent on the turbo compressor housing outlet and the plenum, then install the new hose using a hi-temp RTV or silicone. The newest turbo hose clamps are a superior design to what GM used for the first several years of 6.5TD production. I'd get the newer style clamps, and tighten them well - at the initial installation, then again a few days later.

MP

[gymcarm]

Thank you MP.

Is there anything special about the rubber used? It seems that it would need to be heat and pressure resistant. Any idea where to get one?

The clamps I have have springs under the nuts very much like the ones in the photos used to illustrate the water injection in the new article. Are those the good ones?

This leak is just like making a balloon squeal by "choking" it after you blow it up. Very annoying after just a short while.

[More Power]

The rubber hose is made to work with the high temperatures and boost pressures found in the 6.5. I'd just get a new GM part. I recommend new because the original will be oil-soaked and the RTV won't stick too well no matter how well its cleaned. And, I wouldn't run the engine for 10-12 hours after the hose/RTV installation (if it's an air cure type).

Yes, the clamps shown in the water injection article are the good ones.

MP

[patrick m.]

i wouldnt be surprised if you discover that the leak is not the source of your noise.
if your leak is small enough that you had to use soap to help locate it, 7psi would hardly push enough air out at the leak point to macke much noise.
(and at cruise speed, preasures are much less)

This assumes you are running stock boost levels.

[joed]

I had a similar squeeling noise lately - it only occured at 10 psi and above. The turbo response was also rather slow in general, seemed to take more fuel to make boost. I guessed that the turbo bearings were starting to go, this with 121K on the truck.

Last year I purchased a used GM-8 turbo off e-bay, and changed the turbo a few weeks ago. Now, no more squeeling and much better overall turbo response.

Joe.