Daniel-EL

My Feedback: (9)

I have several four-strokes...nice engines but they all have a common problem. The exhaust pipe/muffler won't stay secured. Every flying session I have to stop or land early and tighten up the exhaust system. I have tightened most of them up as much as I dare - in fact I broke the head exhaust flange on one engine - but to no avail. Any tricks out there about this that can solve the problem for me?[]

Thanks.

65 Chevy

My Feedback: (1)

I have cured this in two different ways.
Teflon Tape on the threads, even under the jam nuts, and blue locktite. If they are really stubborn. meaning that the blue locktite doesnt work, you can use red (High Temp, High Strength) Locktite, but you may never get them apart again. Red locktite requires 1300 degrees or more to brake down and loosen is I am correct with the numbers. I'm sure someone will correct me.

LANNYBOB

65 chevy is correct

Flyboy Dave

My Feedback: (21)

I've had good luck with the teflon tape.

FBD.

Kmot

My Feedback: (24)

There is another method, albeit rather complex and requires some mechanical skills and extra tools.

You can drill a hole in the exhaust nut, and then safety wire the nut to the head.

You need to buy a nut drilling jig:



With this tool, you drill the corner of the nut. Then you use stainless steel aircraft safety wire:



After you mount the exhaust pipe and tighten the nut, you run a piece of wire through the drilled nut and then around the cylinder head, tightening and twisting the wire ends together. The nut will not loosen again until you cut the wire yourself.

http://www.whizwheels.com/Tips/safetywiring.html

Daniel-EL

My Feedback: (9)

Kmot, this is the professional way to do it without doubt. Being a ham-fisted, impatient modeler, I'm going to try the teflon tape method first. Thanks all for the tips. BTW, my first car was a '65 chevy SS convertible. Landed my first wife with it.

65 Chevy

My Feedback: (1)

Great to hear about the 65 SS Convert. My Baby is a 65 BelAir Wagon. I use it as a business car and a tow car for our gear when we attend several Midwestern Car Shows. It is a Wagon, but in process of making it an SS Clone

Ernie Misner

The trick seems to be tightening things after the engine is hot along with the teflon tape. Maybe I've been lucky so far, but after checking the tightness after a couple of hot runs, then it's staying nicely in place.

What I really like about using the tape and getting things snug is that the leaks and castor mess on the pipe and muffler are non existant. The mufflers that become all castor stained is from slight leaks that build up.

Thanks,

Ernie

hanoiboi

I used teflon tape on my Keleo twin exhaust header (OS-160FT) and it stopped the nuts from backing out as they tended to do after a few flights. However today the right jug side exhaust header flange busted clean off![:@]

Guess I'll send her back to old Kelvin and see if he can fix it for me. I must have excessive vibration somewhere, but the prop is balanced perfectly, so that ain't it.

Edge3644

Get reliable insurance!!!!!!!!!!

blw

My Feedback: (3)

I've had good luck by swabbing epoxy in the threads of the manifold and letting it dry. It has held my problem mufflers without a problem.

Globemaster3c17

Putting red RTV silicone works great for locking threads, it adheares to various materials, yet isn't too strong so you can take things apart when you need to. I put it on everything.

blw

My Feedback: (3)

I'll try the red RTV next time.

Daniel-EL

My Feedback: (9)

Here's one exactly like my original beauty. It wasn't fast (283/2-speed powerglide), but the girls loved it.

Bhost

My Feedback: (1)

In my experience, the (high temp) RTV, or teflon tape, is the way to go.

Red Loctite begins to degrade at around 600 degrees F, which is still warmer than I would want to heat an engine to remove a broken header pipe. If you want to use a Loctite product for this application, try Loctite RC/680. It's green in color, doesn't require the components to be squeaky clean, will cure without a supertight fit between the components, and you won't need a pipe wrench to remove it.

Harry Lagman

Another vote for red RTV silicone. It has held exhausts fast on my YS, Saito and OS four-strokes and does not present a problem breaking free when it comes time to remove the parts.

The leak sealing is a very welcome bonus too.

w8ye

My Feedback: (16)

Clarence Lee can do this to your four stroke

Iflyglow

My Feedback: (79)

W8ye,
Is that a fix for a broken exhaust flange.

w8ye

My Feedback: (16)

Yes, and/or a stripped out exhaust outlet.