Looking for recommendations for sealing slip joint headers. The joint at the front of the collector shows small carbon patches, the collector exit to side pipes shows more significant carbon. I can hear the pfut-pfut of a leak below 2000 RPM when it audibly goes away (possibly masked or at least not at the notible frequency). I can tell there the exhaust from ahead of the collectors leaning into the engine compartment as well.

The stainless band clamps might be an option at the collector to sidepipe, have to look if I could fit the clamp block somewhere that doesn't cut into the limited ground clearance and would need to remove the existing bolt tabs. They are not an option ahead of the collector due to space (and I've so far not seen them for 1-7/8 tubes).

Sealants I've seen suggested are copper antisieze and copper high temp RTV. The O2 sensor is in the collector just aft of the tube merge, so any sealant will need to be O2 sensor safe.

What have you had good experience with? It's not a frequant driver so wouldn't need to last for thousands of miles before re-applying.

Thanks

 

I've had good experience with Permatex Optimum Red, but usually use it for sort of an anti seize and assembly lube. I suppose it helps seal things up, but if the slip fit is too loose, use a pipe expander for the inner part to gently get it back to proper slip fit clearance.

 

I found Permatex Ultre Red (same?) listed as O2 sensor safe and for use with slip joint exhaust. I pulled the collectors, cleaned and coated the joints (best I can, I can't get between the adjacent tubes at narrowest part) and reinstalled. Let dry for a day before starting. They aren't perfectly sealed but much better. Will see how it holds up. I don't use the car regularly so hope lasts a long time with the limited driving.

 

When I worked on jet engines we used silkolene products, much like this. It worked great!

https://dieselpro.com/detroit-diesel...3&gad_source=5

 

High temp RTV in conjunction with a high quality stretch band clamp that is pre staggered.

If it is something you really care about and are going to keep for a long time I always recommend making the leap to V-bands. You'll never have a problem again.

 

Thanks. I used Ultra Red which so far is working well. Hardest part was getting coverage around the collector inlet tubes since they almost touch.