DLE 55 Exhaust
 

I have a plane with a DLE 55 on it, and after losing the bolts to the stock muffler and a Jtec, Igot new ones and tried blue locktite. That helped a little, but they still backed out, so I tried the red stuff. Same result, a little better than the blue but it still loosend. So I tried more red stuff with lock washers. No change. I finally broke down and safety wired the bolts, and of course that worked like a charm.

NOW.

I have another plane I'm going to be putting the 55 on again. The cowl was already cut for stock DLE 55 muffler. Besides that, from the measurements, a Jtec wrap around wont clear the firewall (the plane has no box). So I'm wondering if anyone had any ideas as to how to keep the bolts from vibing loose? You can't safety wire them because the holes in the muffler they go through keep the bolts recessed. I could put a plate over the holes and safety wire the bolts that way, but then the bolts will be so long I'm concerned they will break.

I'm sure there;s a simple solution out there, I just haven't come across it yet, so please bear with me.

Thanks!<br type="_moz" />

RE: DLE 55 Exhaust
 

This topic has been heatedly discussed before, so I will just pass something on that worked for me. Try using red high temp silicone on the bolts. Permatex is one brand that sells it and you can pick up a tube at your local auto parts store.

Also, make sure the flange of the muffler and the cylinder head are not scored or gouged from your previous mufflers coming loose. If so, clean it up the best you can.

RE: DLE 55 Exhaust
 

Sure...M5 Nordlock washers plus Permatex Ultra Copper. Buy both at McMaSTERcARR. Dip the bolts in the PUC. This isTHE high temp gas resistant silicone seal. The M5 nordlocks behind the bolts will lock things down great.....Torque the bolts down well

RE: DLE 55 Exhaust
 

putting a brace on muffler will help.will help to damp vabration

RE: DLE 55 Exhaust
 

Brace on muffler, and NO GASKET! Use a thin smear of liquid gasket instead.

RE: DLE 55 Exhaust
 

Locktite softens with heat so unless you get the high temp stuff, its not only useless, it liquifies and lubricates the bolt.

High temp stuff mentioned above, and nordlock (called Wedge Lock on McMaster Carr)http://www.mcmaster.com/#standard-lock-washers/=lz52a3 are the ticket

RE: DLE 55 Exhaust
 

I did not mean to put any stuff on the bolt threads. The liquid gasket should replace the exhaust flange gasket.

RE: DLE 55 Exhaust
 

I was addressing the OP's practice of putting blue locktite on the bolts.

RE: DLE 55 Exhaust
 

Just my opinion but I have never had a muffler come loose on a new install using Loc blue with lock washer(new only) As you have experience, the total loss of bolts on not one, but 2 mufflers.......the threads are damaged.........so as you found out, only wire works after the damage is done.

Last on stock mufflers that have the deep hole and don't allow the use of wire........most people don't use split locks because they don't have the proper size split.............finding the proper size is not easy, unless you have vary good hardware stores in your area.
The photo shows how tight these split locks are if size proper....any larger and the locks won't fit down the hole.

My set up is vary similar to some posted hear..........I have split locks,blue loc....no gasket... high temp gasket sealer thin layer.....balanced prop. I have not braced off a stock muffler but I think it would be a good idea.
This has always worked for me.
Good luck

http://img.photobucket.com/albums/v1...psa624f0b0.jpg
http://img.photobucket.com/albums/v1...psd691b03d.jpg

RE: DLE 55 Exhaust
 

I havent had any issues either and I use the stock hardware with no thread locker at all. I just tighten the bolts to the engine after its good and hot. This has worked on all engines even little glow two strokes.


Tighten it while its hot. Tighten it whiole it how hot hot hot hot hot lol