Hi:

Does anyone know what kind of thread lock can be used to secure the pressure fitting
on a Saito 56 muffler?

I have Devcon Thread Locking Compound but it's only good to 250 F. Will this work?

Thanks

I just use JBWeld

I just oil the threads with castor oil to prevent galling and tighten it up. I have never had a Saito header or muffler fall off.

Mine loosened a few times, but I kept tightening it until it stopped getting loose. You could use Permatex Red for high heat applications. You have to have all surfaces clean before using it. Or, maybe swab a little epoxy in the threads. That always seems to work better for me than thread lock.

So much for getting your question answered. I went through this on a tuned pipe and here is what happened. I was using the little blue tube of "Permatex High Strength Red". This works good on most areas and is questionable around heat even though the heat rating is high.

This was not working for me because when this stuff gets hot, it liquifies and becomes useless-----so I was told to use Permatex "Sleeve Retainer". It is still in an identical little blue tube like theother but says "Sleeve Retainer" on it. This is used for sleeve and bearings and such. You will notice that the temp ratings are almost the same but does not liquify for some reason and works great around the engine and is only a few dollars.

You should be able to get it at a NAPA. I could not find it at stores like Pep Boys, Checker or Autzone although they had the regular stuff but not the "Sleeve Reatiner. This should cure your problem

Although I am not an engieer, my experience is that no threadlock, JB Weld or epoxy will hold up to the high heat of a muffler. I just tighten the as much as possible, and I add a safety wire to catch the muffler in the unlikely event it was to fall off.

Safety wire, unless done well, makes for metal to metal rubbing and radio interference in my experiance.

Here is what happened on mine. I have a Jettstream tuned muffler specially designed by Jett for the G2300 Supertiger. It is not a direct bolt on but uses an adapter plate.

The plate gets bolted on to the muffler similar to bolting on any ordinary muffler. There are a couple smaller screws inside the adapter coming the opposite way to attach to the muffler.

Now since last spring it was these smaller screws that kept coming loose after 2 flights and this was extremely reliable and getting me very upset for having to remove the cowl and make a big production over it. I tried Permatex High Strength Red and several others but nothing. After 2 flights it would come loose from the heat.

I put out the word right here on RCU for advise and several came up with the same brand of Permatex but this time using the "Sleeve Retainer." I have not had the muffler come loose all summer and probably 20 flights or so. Nothing gets hot like a tuned pipe. So in my opinion it works

Hey try teflon plumbers tape. I heard that works too .

I think he is talking about the pressure fitting for the vent line......?

If the pressure fitting is comming loose on a muffler then it probably has bad threads on it, or most likley the threads in the aluminum of the muffler are gone. The problem with using ANY retaining compound is that they all go thin when exposed to heat. How do you think you get the stuff loose once it's cured anyway? Heat it up and it breaks it's bond pretty quickly.

It would seem to me that if a muffler fitting had a new peice of fuel line on it the fitting would be unlikley to turn in the threads in the first place, due to the fact that the entire tube would have to turn with the fitting to allow it to back out which is unlikley. If it were mine I would consider getting a new, larger pressure fitting and retap the threads to the larger size.