Exhaust nut repair

[Luca]

Hi all,

I took off my exhaust the other day for repainting and figured I'd also take the exhaust nuts all the way off and go in with the antisieze and really clean up all the threads.

Anywho, the left nut came most of the way off before getting tight again (so, after much oiling and massaging I used the wrench again for the last bit).  My port threads are fine, but the left exhaust nut has some galling right at the initially engaging threads.  It doesn't look too bad, and I was thinking I could fix it with a thread file rather than replace the whole thing.

Does anybody know offhand what the thread size and pitch is for the exhaust nuts?

[steve hawkins]

They are pretty cheap new.

Thank your lucky stars that your threads on your heads are okay.

Normally I/we recomend cutting the nuts off, if you do not know when they we last removed, so saving the threads on the heads.  These cost a lot of money to repair.

My vote is:  Chuck em, replace with new and make sure you put some copper ease or the like on the threads before you put the new ones on.

Having done this you are set for the forseable future.

Cheers

Rev Light

[montmil]

Don't know how easy it might be to find an appropriate size thread file. Me? Since the exhaust stub threads have just a little damage at he engagement point, I'd probably dress the threads with a small, die makers file set and call it good.

Check the butterfly nut before refitting or buy a new one -or two. Anti-seize on the threads.

In the past, I have used valve lapping compound, mixed with a bit of kero, to work the nut on and off the exhaust stub. That worked out well and mated the threads for smooth ops. Clean up all the threads before applying the anti-seize compound.

Having had to saw off one of my nuts -easy boys, that's a bit o' Airhead humor- I now loosen and reapply anti-seize as an annual ritual.

[Luca]

Monte, it's the threads on the nut that are damaged, not the stub

Nuts probably never came off of this bike.  I finally got an exhaust wrench so I could do the annual service and also repaint my exhaust.  They weren't that hard to get off though.  A little penetrating oil and some rubber mallet action got em free quickly.

I know its dangerous forcing the nuts off, but I had the thing almost all the way out and it was plenty oiled up, so I made a judgement call and give it a little persuasion.

Since the whole thing is aluminium, I think now I'll just try some gentle shaving with a razor blade.  Thread file would probably be more expensive than the nut itself.  Didn't realize they were only $20

[georgesgiralt]

Hello !
to clean that area I use a stiff bronze brush and elbow grease. Then, a bit of kerosene to finish the cleaning and a copper high temp grease on refitting. That's it.

[tvrla]

I've had that problem before - an exhaust nut with rough threads. As I recall, I found a large bolt - maybe ten or twelve mm with the same thread pitch. Go through your bolt bin or hit the hardware store. I think I filed a notch length-wise across the threads and used that like a crude thread file.

[disco51]

Going through some of the annual maintanence tasks on my new to me R65.  
Reading this thread, my question is...
Would you recommend going ahead and buying the $35-50 tool to check to see if you can actually get the exhaust nuts off and apply the antiseize?  I'm actually curious to see if the things will come off, but then I'll find myself trying to chop them off with a dremel, then ordering new nuts and worrying about the threads, etc.   Ultimately finding myself spending more money on a problem I read about but wasn't bothering me... at least for now.  
Always the question with a 34 year old bike!
Unless someone near Augusta, GA (soon to be Nashville, TN) has an exhaust wrench they'd love to let me use...

[Luca]

Wirespokes, I ended up just getting a new nut since they are so inexpensive.  However, I'll keep your thread file idea in the ol' mental inventory.  Might come in handy in the future.

Disco, I'd say the tool is worth getting and the anti-seize worth applying.  My finned nuts came off without too much trouble, but the bike also had very low miles on it.  Lots of penetrating oil, maybe some heat cycling, and tap on the wrench with a rubber mallet.

The exhaust will come out without fully removing the nut (and I was just painting the exhaust), but I figured I'd do it properly now and get anti-sieze on all the threads and never worry about it again, except for yearly greasing.

If you ever need to remove a cylinder, replace an exhaust piece (I suspect crossovers are the first to go), or pull the engine, that exhaust is going to have to come out.  Why risk cutting the nuts and mucking stuff up in the future if there is a chance you can get them off cleanly now and give em some proper lubrication?  That wrench is cheaper than two nuts and a cold chisel...  and you won't get stuck waiting for parts in the mail when your old finned nuts are seized in place and have to be cut off.

[tvrla]

The exhaust nut wrench is one of those tools you'll need as an airhead owner, along with an alternator rotor puller bolt and a long 10mm 12 point wrench for the u-joint bolts.

Once you have the wrench, attempt to unscrew the exhaust nuts. If they don't, tighten them back up and run them that way till the new ones come in.

That way you'll know what you've got. If they come off, you're in luck and can auntie-seize them and be good for another couple years.