So, posted this a while back, but looks like forum is really cleaning up on old threads. 2 tapered gasket installs on 98 Ultra front exhaust. Both leaked with new studs and nuts. THC suggested pics of pipe end, as I think these are twinkie pipes because of welded O2 bungs. Tapered or flat gaskets, guys? Maybe double up?
Those don't look bad at all, actually better than mine. One tapered OEM gasket should work fine. I don't think you need to double up, or shouldn't have to. Those gasket should "squish" and make a nice seal.
Those don't look bad at all, actually better than mine. One tapered OEM gasket should work fine. I don't think you need to double up, or shouldn't have to. Those gasket should "squish" and make a nice seal.
Those look fine to me, too.
When I built my Sporty, I made my own exhaust flanges and they don't look nearly as nice as yours. Still sealed up just fine (with tapered gaskets).
I've always used OEM tapered and have re-used them many times without any problem, so long as they're not removed.
Take the flanges off and check them for flat. Replace the lock rings if they're bad rusty. If the flanges are warped, it's easy to flatten them with a hammer. Your pipe ends look good.
Put everything together loose - all the way back to the mufflers. Grab and wiggle around till the head pipes look flush with the ports/gaskets and tighten them first. Not too much, they don't need much torque at all!!! Then do whatever you have to in order for everything else to line up /tighten up well.
Great advice, all. Yes, the flange is warped. I have a welded bung about 4" downstream of the flange. Guess I could scratch-mark a cut before the bung, flatten the flange, slip it back on with a new retaining ring , and tig back together with stainless fill rod. Cheaper than new pipes, since I can do it for free. Or "shave" the bung off and tig a patch in. May be a better way to go about it?
So, posted this a while back, but looks like forum is really cleaning up on old threads. 2 tapered gasket installs on 98 Ultra front exhaust. Both leaked with new studs and nuts. THC suggested pics of pipe end, as I think these are twinkie pipes because of welded O2 bungs. Tapered or flat gaskets, guys? Maybe double up?
Those pipes are designed for flat gaskets.
That said you can get them to seal with tapered gaskets but you have to tighten them down pretty good.
Those pipes are designed for flat gaskets.
That said you can get them to seal with tapered gaskets but you have to tighten them down pretty good.
Yeah, may be. They look like mine (pre-'96 pipes) but I've NO experience with Twinkie parts at all so I'll leave the gaskets to others.
Use lock ring pliers to spread the ring and take it off the head end. Then the flange comes right off - that's why they're made that way. If you "spring" the lock ring too bad, they're cheap and not hard to find. Some parts houses keep them or truck repair shops. I used to have a box full of them from building truck transmissions....
10-16-2019, 03:09 PM
Exhaust gaskets
