Do you have a "sleeve" in your Exhaust Donut Gaske

[LaGrasta]

This thing is really restrictive as it a much smaller inner diameter than the actual exhaust pipe. It's like shoving a venturi in the pipe, but not nearly that smooth. I took it out and added a larger donut to see if I could get it to seal without it. No luck.

 

[The Plankster Prankster]

the one for my 300 fits over the end of the pipe and into the manifold, whereas yours sounds like it butts up to the end of the pipe ?
is that section of pipe original or aftermarket?

 

[wallaka]

Yeah, I've had problems without it too. Seals for a couple weeks, then starts leaking again. I think this time I'm going to cut it down to the height of the donut and weld it back in.

 

[Mercury Mike]

Weld the pipe to the manifold where the gasket would, break the pipe a little lower, and put a rounded off triangle flange there. =)

 

[Stubby]

When the exhaust shop did mine, they made a new pipe all the way. They flared the pipe and cut the next smaller size and made a new end. They tacked the smaller pipe inside the flare. The donut tried to leak a couple of time from the bolts trying to get loose. I carefuly tightened the nuts until it setteled in and stopped trying to back off.

 

[wallaka]

Weld the pipe to the manifold where the gasket would, break the pipe a little lower, and put a rounded off triangle flange there. =)

That would work...I think I'm just going to buy a header instead. They sound cool.

 

[wallaka]

Finally got tired of downpipe problems...ordered CI Jet-Hot Sterling coated header, finally. Can't wait for it to get here...!

 

[LaGrasta]

Nice, new headers! And how are you attaching them, ARP bolts, lock washers, tab washers, etc? Ultra Copper Sealant, with no gasket?

 

[wallaka]

I'm gonna use Ultra Copper, no gasket and see how it works. And I already have it studded so...just grade 8 studs and nuts.

 

[Frankenstang]

Resurrecting this thread because much searching did not yield a whole lot more information, not sure if the issue mentioned here is similar to what I might be facing.

I'm getting ready to finish the conversion to 2" exhaust, front to back. I finally got the 68 head pipe from CJ Pony (prices are good but backorders are a pain). At any rate, I noticed on this new head pipe that the length of pipe extending beyond the donut seat (flaring) is not very long at all...just about the height of the donut itself. On the old 1.75" setup the pipe extends quite a bit further (and therefore up into the manifold quite a bit). However, looking at the new manifold and it's cut & recess to receive the head pipe and donut they seem to match up visually.




So the question is, will this new head pipe, donut and manifold configuration be sufficient to make a good seal? Does there need to be a smaller diamter 'sleeve' extending above the donut and into the manifold to complete the seal? I'm concerned about the donut seeing full exhaust heat & gases and how that will hold up.

Trying to head off potential leaks, and I'm going to have the muffler shop weld a tip on the tailpipe after mock up and prior to full install, so wondering if I need to have them fab some sort of sleeve for this at the same time. I'm doing actual complete install of full system myself as I'm going with a clamped version to keep it modular for future work access.
Thanks in advance for any thoughts on this!

 

[wallaka]

The interior pipe is just to locate the donut gasket, so it shouldn't matter too much how far it extends.

 

[Frankenstang]

Thanks wallaka, I guess I was picturing a longer extension above the donut helping secure the pipe from rattling/working loose over time...as well as shielding the donut from direct exhaust gas. I imagine I could track down an exhaust mount to connect to the block to prevent excessive motion on the joint.

 

[Ronbo]

I'm gonna use Ultra Copper, no gasket and see how it works. And I already have it studded so...just grade 8 studs and nuts.

I've never used gasket sealer on a header. Old school training I guess and things have changed immensely. The Ultra Copper will work in place of a gasket? I'm pretty frustrated with trying to seal a header to an AUS head. Could make for a happy day!

Ron

 

[LaGrasta]

The copper solution works as well or better than anything I've tried, but still not 100%. I would use it again before buying another gasket.

Now my donut is leaking again…

 

[66 Fastback]

I have seen both metal and composite donuts. You might try the softer composite donut if you have trouble sealing.
Doug

 

[Ronbo]

Now my donut is leaking again…

Don't let that one get out to the law, could be trouble! :rolflmao:

 

[Ronbo]

Stupid question here...will that Ultra Copper work on the intake as well? It's appearing like my exhaust leak has burned up my home made intake gasket.

 

[LaGrasta]

I guess it would work just fine, but high-temp silicone may be even better. I can't know for sure as my 170ci intake is integral to the head.

 

[Ronbo]

Shoot, anything is worth a try at this point Thanks for the reply LaGrasta and good luck with fixing your's!