engine mess

[Rappy1]

Just thought i would post to let you no a good way of sealing themuffler to the engine with out even a drip of fuel getting past the gasket.
I have always had a problem on r/c nitro helicopters where the muffler would leak fuel and track its way around the bottom of the frame, this anoying problem has covered the back of my car infuel stains and black marks. To fix this problem it is simple use an alloy gasket between the eng/muff and coat both sides with blue lock tight. I have tryed rtv silicon in the past and it has not worked. Leave heli for a few hours to allow locktight to sink in and harden and now you have a leak free exhaust. After 15 tanks of fuel still no sign of leaks and airframe still clean. good luck

[heli-cuzz]

Good idea, rappy. :cool:

I use the automotive gasket material and replace it after about 4 gallons of fuel.

[theBZA]

BLUE LOCTITE?

Blue loctite will turn to a liquid the instant the engine gets up to temp. Once a liquid, it is totally useless, and therefore, won't work.

Your good-seal luck is based on the fact that you likely had a smooth, even seating surface prior to bolting on your muffler.

The proper way for bolting on your muffler, is to tighten good and snug. Fly around a few circuits. After 2-3 minutes, land, and retighten your muffer bolts WHILE ENGINE IS HOT!!! If you had the little lock washers on there, your muffler should never come loose.

If you insist on using any loctite at all, use the Red Loctite on just the muffler bolts. Again, blue is a waste of time because it turns to liquid at a much lower temp.

The red stuff is the same I use on the prop nut, and engine mounts. Don't use it anywhere else on the heli, as it will be a bugger to take off.

Either go with a TRUE, flat seating surface, or the RTV compound. Both will work. But when using the rtv, use only a tiny bead. Should be about a pencil line.

[tdswan]

They also make high-temp loctite, which is what I use on my muffler on my gasser. As for my Raptor, I've got extra-long bolts on it with nylon nuts on the other end since the muffler holes stripped out from coming loose. IMO, the main reason a gasket fails is because the bolts come loose and allow the gasket to blow out....it doesn't take much. With mine bolted with nylon nuts, I've never had a gasket fail.

Yes, you should heat the engine up to get it truly tightened.

Red loctite is most commonly used to "meld" bearings to the shafts they support and holding the fan hub on in a heli application. If you tear down your heli, notice how smooth and shiny the shafts are behind the bearings if they are not loctited to the bearing. You don't use it much on 30-50 glow machines, but on larger helis, and ESPECIALLY gassers, you use it a lot on bearings. Without it, the shafts and bearing races would wear against each other at an alarming rate.

[theBZA]

Yep. Just stick with the RTV compound. Use that, or nothing at all. No paper gasket, no metal gasket. Nothing.

In fact, Im going to WalMart right now, To pick some up. That, and RED LOCTITE for the prop nut on my new engine.

Remember to only use the SMALLEST, even amount. Excess is really bad, as clumps will break off and kill your glow plug.

[Rappy1]

[QUOTE=tdswan]As for my Raptor, I've got extra-long bolts on it with nylon nuts on the other end since the muffler holes stripped out from coming loose. IMO, the main reason a gasket fails is because the bolts come loose and allow the gasket to blow out....it doesn't take much. With mine bolted with nylon nuts, I've never had a gasket fail

Thats a real good one regarding the extra long bolts with ny-locks. there are a few helis where i fly that have bought threaded rod and fiwed to ny-locks at each end which stopped the problem of working loose. As for rtv silicon you get what you pay for, on models you wouldn't want to use the cheap stuff as the methanol would desolve it. When i was working as a mechanic i used to notice anywhere orange coloured rtv had been used that had alot of oil flowing or sitting around would leak and also the amount of stringy bits you would find in the sump and on the oil pick up. At Mitsubishi we used a high grade silicon that was smell less and would seal any thing. it was the silicon the manufacture would use on any part that needed sealing on the engine. this silicon was not cheap around $80 nzd for a 100ml tube but it would never fail and was so good you would never have to use a gasket. So make sure if you are going to use rtv it is a high standard one or you are just wasting time.

[theBZA]

The stuff I use is available at WalMart in the automotive section.

It is by Permatex, High Temp RTV Silicone Gasket Maker. Comes in a red tube, less than $5 for 3 oz. (more than enough).

It will withstand up to 640 degrees F.

The directions on the tube are different from my method.
I put a thin bead on the muffler alone. I spread it evenly around, just enough to go around.

I let it dry first, THEN mount the muffler.

The manufactures directions say to spread, and bolt together while wet. I dont do that, as it will spread itself to thin.

As far as the stringy bits, it won't happen as long as you have a good tight seal.
Use it sparingly enough, and it just won't happen. The only times I have heard of problems, is when guys use WAY TOO MUCH, and oozes all over the place. Thats when you get the crap in your glow plug. That sucks.

Coming from the guy who says, "you get what you pay for", he suggested to use BLUE LOCTITE?

[tdswan]

Coming from the guy who says, "you get what you pay for", he suggested to use BLUE LOCTITE?
Easy, guys! It's just an open flow of ideas! Let's not make it personal! :)
Starting to sound like RunRyder around here! I've been guilty of it in the past on here as well. :o

[Rappy1]

At the end of the day i am not forcing anyone to use loctite i am purely stating it works well for me and it has not desolved so when it comes time for removal ya have to tap on the muffler lighly to break the seal and you can re-use gasket as if need be. on a paper gasket i would not use it but with metal ones it works fine. I have used rtv before and never really had a great deal of luck with it but does not mean it will not work, you may need to play around until you find what is right for you Hey at least now you have two different ways of sealing

[heli-cuzz]

Easy, guys! It's just an open flow of ideas! Let's not make it personal! :)
Starting to sound like RunRyder around here! I've been guilty of it in the past on here as well. :o

To late buddy, its more than personal, its my heli we're talkin' bout. ;)


Damn it td, my automotive paper gaskets are the best. :p

[chaos]

My cat seems to think everything should have a coating of cat snot. Maybe it helps. Who am I to argue with a cat.

[Rappy1]

My cat seems to think everything should have a coating of cat snot. Maybe it helps. Who am I to argue with a cat.

Come on mate don't go giving people false info Cat eye snot is ten times better due to its rough texture

[team222badbrad]

No need to worry, my muffler is sealed with an air gasket.