3196 exhaust leak

[Russ Calasant]

I have an exhaust leak on a CAT 3196 and found it to be the studs on the turbo housing to exhaust manifold. Two studs on left side were broken. The two on the right side had been heli-coiled so must have been an issue. My question is regarding the surface of the turbo housing itself, I am told by a CAT tech it needs to be machined and there is a side hustle for $900 cash - he knows a “guy”! We are now at $400 which is still rediculous to machine it, can’t I just use some sandpaper ? It has a gasket! And what about the manifold surface - it’s not being machined.

 

[ZZ13]

I have Cummins so not quite the same thing I guess. But I've had my turbos off several times as well as done them on a friends boat. I checked both mating surfaces with a straight edge in multiple directions to make sure nothing was warped. I carefully scraped off any residue gasket material and smoothed the surfaces with a fine sandpaper attached to a flat object. Then I cleaned them really well with a solvent. I put in new studs and a new gasket. Also us Cummins guys like to use high temp rtv on both sides of the gasket so I applied that. Then I bolted it together and called it a day.

Not sure if that helps you, but that's what I did.

 

[dtfeld]

I would check flatness as ZZ13 suggests. If relatively flat, maybe a couple thousandths, replace the studs and gasket , then call it a day. You could also call CAT and get the spec.

At the end of the day, a nice flat surface and the right bolt torque should give you good results.

If it is warped, a machine shop should be able to do the work for less than $900...