Topic: Getting some blow-by past the exhaust clamps

[grumpy]

750K3
341 pipes...

I found some carbon build up on the mounting flanges of 2 of my stubs. I looks like exhaust has been escaping past the pipe/stub joint and leaking back toward the engine.
Looks as if the clamps aren't sealing completely. The clamps were tight.
The carbon is not all the way round the stub - just in a few places. So the seal didn't fail completely.

Any idea on how to seal this up?

Is there any sealant goop that will withstand the heat & pressure?

I thought about installing a thin steel shim around the stub but I bet that would be a PITA to get the pipe to slip over...

[Dimitri13]

Kind of a dumb question, but did you put the exhaust gaskets in?

[jlatkins83]

Those crush gaskets can be a pain in the butt, but do the best job. I have also used high temp. copper rtv as a sealant. Some people might scoff at that but for a quick fix that is reliable it works, but I wouldn't do it as a permanent solution.

[grumpy]

Kind of a dumb question, but did you put the exhaust gaskets in?

Yeah gaskets are fine - but that's not where the leak is.
It's leaking from where the pipe meets the stub - not where the stub meets the head.

[MCRider]

Kind of a dumb question, but did you put the exhaust gaskets in?

Yeah gaskets are fine - but that's not where the leak is.
It's leaking from where the pipe meets the stub - not where the stub meets the head.

If they are stock pipes and spigots, I would suspect the clamps aren't drawing down tight. Maybe the bolts have been changed out to where the threads are too short and stopping before the clamp is done drawing down?

[grumpy]

All stock...

Actuallly, as I look at this, mayby the clamps are stretched....
Damn, those are expensive!

[MCRider]

All stock...

Actuallly, as I look at this, mayby the clamps are stretched....
Damn, those are expensive!

Sets on ebay usually reasonable.  If the clamp gap is closed, I might open them up and grind/cut some material out so they'll clamp harder.

Also we're back to your idea of slipping a shim in there. I'd put it between the clamp and the pipe, not the pipe and the spigot, which would be hard to do.

[grumpy]

[Also we're back to your idea of slipping a shim in there. I'd put it between the clamp and the pipe, not the pipe and the spigot, which would be hard to do.

Good idea. I try that.


I wonder if this goop would work...
http://www.amazon.com/DEI-090400-Gasket-Eliminator-Sealant/dp/B006J8HY88

[MCRider]

I think that goop would need to go between the pipe and the spigot, to be effective. With stock parts, and good clamps, it should seal without any help.