Loctite 243 on exhaust nuts?

I have never had a problem keeping the exhaust nuts on....it has always been a problem getting them off without taking the threads in the head with them. If yours keep coming loose, I would suggest you bodge up some sort of wire security system, or a keeper setscrew, rather than risk bonding the nuts to the threads in the head.
 
Without trying to go into a long winded statement, it depends on the condition of the threads in the head, ditto; the exhaust nuts and what material it is made from.
If all are in good condition all should be well, but you have to tighten the nuts again when the engine is hot, and Dural nuts are probably the best.
 
I had constant problems with the exhaust nuts loosening . Did the wire bit , new tab washers , etc. I switched to bronze exhaust nuts ( roses ) and tightened them several times while hot and they have stayed tight for three years now .
 
"General Classic Motorcycle Discussion" category

Are you talking about Norton nuts?


Size of bolt?

Design of bolt?
 
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I use this on my YPVS through bolts.


Loctite 243 on exhaust nuts?
 
Anyone using this to keep nuts in place?
Most Loctite thread lockers, including 243, have a ceiling temperature of about 250C so would be useless in this application

Better to make sure the nuts have a similar expansion rate as the head alloy, such as bronze and some SS, and are tight.
 
A friend used some sort of Loctite on a Norton single exhaust rose. Come time to remove it, he could not. Ended up cutting through the exhaust pipe to get the head off and then took it to an engineering place to let them get the nut out. An expensive mistake and lesson learned.
 
Loctite is glue, it simply glues the nut into the thread.

The purpose of those exhaust nuts isn’t to be glued into place, the purpose is to provide proper clamping of the exhaust pipe and gasket to the head.

The only way to ensure this proper clamping is to tighten them properly, especially after fitting new gaskets, whilst the gasket compresses over time and heat cycles.

Glueing the nuts in place won’t achieve any of this. In all probability it will cause more harm than good as the glue will make you think things are tight when they are not, and the consequent chattering of the exhaust pipe in the head could cause issues.

IMHO these nuts stay in place if checked once in a while. If extra safety is desired locking wire would be better than glue. Though beware, some folk get carried away with those lock wire pliers …

Loctite 243 on exhaust nuts?

Loctite 243 on exhaust nuts?
 
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