The exhaust on my 1983 XLX has a crossover (runs from the front pipe to the rear pipe, just below the carb). Where the two pipes meet (in the crossover) there is an exhaust leak. What is the best way to fix that? Thanks.

 

remove the exhaust and replace the donuts on the balance pipe -- and glue the head pipes and re install the whole thing

Hi temp silicone ( red ) works real well some one else might have a different way but its what we do in my shop an hours labor - jz

 

Is the purpose of the balance/crossover pipe to improve exhaust backpressure or is it just to balance the amount of exhaust leaving each muffler?
The weird thing is that about an inch into the balance pipe the rear exhaust has a plug (welded by the looks of it). So there is no exhaust making it all the way through the balance pipe. I don't know if that's a modification added by somebody before I bought the bike or if it came like that from the factory.

 

i dont know anything about what may have been done or not with out pictures of what your seeing

the balance pipe was an 80s harley idea that sort of caught on with harley over the many years, does it do something ( YES ) in the 60s Ford did extensive testing and found more torque with it in any app they tryed, so my guess harley did the same thing and found power using it < ut cost them money to add it so ya gotta think it does something - if you like it stock leave it if not change the pipes - jz

 

You are right to question how to make that connection leak free. I had that exhaust on my 1980, and when i finally did make it leak free my tuneup changed hugely. A leak there makes the tuneup very lean.

My experience is that the two parts of the crossover do not line up well. And while the OEM gasket 65781-82 is essential, it is not sufficient. I use the Permatex Ultra Copper as it has the highest heat rating of the Permatex series of hi-temp silicone sealants; use as much as needed to ensure a very good seal.

One thing i discovered was that it was impossible to remove just one part of that exhaust system for general maintenance, and still get a good seal on re-install. I had to remove both the front and rear, do whatever maintenance, then carefully re-install the whole thing - otherwise it leaked at the crossover.

I too would like to see a pic of the blockage that you are referring to. Sounds very much to me like something some PO added in.

To seal exhausts at the cylinder heads i try these ...

1. ensure that each header has 4 slits, not just 2 as do some headers
2. apply Permatex Ultra Copper to the inside of each header before install
3. use pop can shims between the clamps and the pipes. After final tightening, which must be very tight, check if the clamps are fully closed; if they are fully closed then you need the shims as they will not be tight enough.

To install this exhaust system i first install the whole thing with all bolts finger tight only; then final install at the heads; then at the muffler/header join; then at the muffler - with a lot of going back and forth among these parts.

Congrats to JZ on getting this tedious job done in an hour!

 

I will take a picture and post it in this thread next weekend or so. I ordered the 'gasket' and it will be here in about a week. So I'll be taking the exhaust apart to install it. I'll take a picture then.

 

For what it's worth, all I did was install a new crossover gasket on mine (also an '83 XLX) and it sealed fine. Everything has to line up correctly, though. I also have a heat/carb shield on the crossover, which clamps to each side. That may help to stabilize the crossover connection a bit, too.

 

Hey 83XLX,
Since we have the same bike, does your crossover have the plug like I described on mine? If somebody added it before I bought the bike I'm thinking about drilling it out. The way mine is right now there is no flow all the way through the pipe because of the plug. Weird.

 

No, my stock exhaust (black) and this '83 XLH exhaust (chrome) both are open each way - no plug in the crossover.

 

Now that I cleaned the carbon off, it looks brass. Looks to me like something somebody welded in back in the day. I wonder why? I'll probably try to remove it somehow.