Exhaust Gasket Type and Chasing Leak at Port

[The Standard]

Added some new pipes that were supplied with the exhaust gaskets in pictures. Have some leakage and wanted to know is this type of gasket supposed to be oriented as pictured?

I am used to the crush type gasket that butts up against the end of the pipe face and spreads against the exhaust port face.


The gasket pictured is hard and doesn’t seem to spread out upon tightening the headpipe flange.

With the gasket removed, the pipe feels like inserts up until the collar contacts the exhaust port face.

Not sure if gasket is supposed to slide up on pipe against collar or stay at contact point of end of pipe and exhaust port face - sandwiched between them.

 

[gggGary]

Are you getting the flanges in and Fairly snug before tightening the rest of the exhaust mounts? is this a two in to one pipe?
Point being; getting the gasket in and the pipes inserted straight into the head is #1 on getting a good seal. If the pipes are rigidly attached elsewhere you might not be able to get a tight seal at the head. Pic of the pipes?

 

[The Standard]

@gggGary,

The pipes are standard run of the mill TT pipes offered by Dan at Pandemonium. They attach at rear via a flange on each that bolts together and then the right pipe secures to one of the Starter mounting holes.

I ended up coating both sides of the exhaust gasket with Red Permatex High Temp gasket sealant. We'll see what holds for results this weekend.

I did for the most part this time mount the pipes in the ports with the flanges tightened about 75% before loosely attaching the rear securing hardware.

I may spray WD-40 around the pipe-to-port junction to see if a leak is detected when first starting. Concerned that once the pipe gets hot that WD-40 may burn on the pipe and stain the new chrome.

 

[5twins]

If you have leaks, the new chrome on those pipes will blue up badly and almost immediately. Even with no leaks, it's probably going to turn blue eventually on you.

From the looks of those pipes, I don't think that collar that the gasket fits against is sealed to the pipe all the way around. It looks like it was just spot welded to the pipe in a couple places. That means you may get exhaust leaking "through" it, between it and the pipe. Looks like it may have been happening already by the bluing evident on the pipe around it's outer end. Yes, I think you're going to have to apply high temp sealer around the inside edge where the gasket sits.

 

[The Standard]

@5twins,

I am of the same opinion. I think that discoloration was exhaust seeping under the color. Yep, no weld bead all the way around the collar when looking at it from the end.

We'll see if the sealer addresses this. Will be at the 24 hour cure mark by tomorrow. So used to just needing the crush type washers for a good seal on other bikes.

Regarding the discoloration in general, I always thought the pipes blued when they got too hot from a lean AFR or sitting in traffic with no air cooling them?

I am hoping all that richening up of the mixture will result in just some slight golden coloring near the head. Definitely abandoned all hopes of that nice shiny chrome finish lasting in that section of the pipe.

 

[The Standard]

@5twins,

What is interesting in looking at this photo where you responded to a related post, is that the exhaust gasket sits right up against the end of your 1.5” headpipes.

On my headpipes that same style gasket slides past the end of the head pipe, up onto the pipe and is up against that collar in mounting the pipe.

I am curios to try your homemade torque insert idea in cutting the ends off some stock headpipes. What is the length you made the cut off of the ends from that larger ring of the part of pipe that goes into cylinder pictured?

Wonder if I will have to source longer exhaust studs with the added stock pipe ends?

 

[5twins]

The end of the stock headpipe is a machined metal part. It extents into the headpipe from the sealing flange about the same distance as it extends out the other side into the head. I cut it a bit longer, maybe an inch or so, then trimmed it back. If you look closely at that first pic, you can see the end of it inside the part. The double wall pipe is welded to it. To make it fit into my 1.5" headpipe, I had to remove the outer layer of pipe. I cut through it and "peeled" it off.

My MAC headpipes had a very small sealing flange and it wouldn't stay on the seal ring as I tightened the pipe down. They leaked like crazy .....

This was the whole point of making the inserts, to center the pipe and hold it on the seal ring. It worked very well and even though I didn't do it for this, I got a nice AR insert in the deal as well. Now, I know these are needed for larger diameter headpipes to restore low and midrange power, but I think it helps with the 1.5" pipes as well.

On yours, to use the insert, you may need to cut off that end section of pipe that extends out past the collar. Make the end of the pipe flush with the end of the collar. No, I didn't need longer studs to mount this, but I did have to leave the lock washers off.