Exhaust Deflector for a 4-Stroke?

I just finished building a Proctor Sopwith 1 1/2 Strutter. (My third proctor kit, and all have been tons of fun to build.) Anyway, I mounted the .70 4-stroke engine inverted. Only problem is that the muffler will direct the exhaust directly onto the axle's bungee cord shock absorber.

I understand that the usual 2-stroke exhaust deflectors will not handle the higher temps of 4-stroke exhaust. But I don't know what to substitute. I'm only looking to deflect the exhaust maybe 20-30 degrees or so.

Any ideas for a pre-made 4-stroke deflector or material to make a home-made one?

Thanks in advance, Brion

Reply to
Brion
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Brion,

If you're trying to deflect the exhaust after it leaves the end of the muffler, the usual 2 stroke deflectors will work fine on your OS .70FS.....Keeping one attached to the end of the muffler can be a problem.

However, if you need to use the deflector directly on the header pipe, it will burn through eventually.

I've used "Aero Trend" brand tuned pipe coupling with good results on a couple of my Saito 4 strokes fastened to the header pipe (1.20 & .80) Keep in mind Aero Trend doesn't recommend using it on 4 Stroke headers. The stuff I've been using is blue in color.

BTW. I heartily agree ... Proctors are great kits.

Happy Flying, Mike

Reply to
Mike

On 5/13/2004 9:56 AM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

If it is the exhaust coming from the muffler, change the exhaust pipe angle at the engine. If that isn't possible, I have seen "swivel - multi angle" adapters available for Saito that go into the engine and the exhaust fastens into the adapter. They can bet set for any position. I don't know if they are available for your make of engine, but it might be worth checking out.

Another possibility for diverting the exhaust gas from the end of the muffler is the Hobbico exhaust deflector. To get it to stay on the muffler tip, use your dremel and cut 2 SHALLOW groves all the way around, then clamp the deflector on. If you are afraid of the heat problem, they have the blue "silicone type" exhaust tubing you can use. This stuff is about 3/16" thick.

Hope this helps.

Reply to
Ted Campanelli

I disagree that a two stroke deflector will work. I have tried it. It burns up. The only possible item is a piece of silicone tubing (tuned pipe coupler). The problem for me has been finding some small enough!

Reply to
jeboba

If it's an O.S. engine, Tower stocks O.S. flex exhaust deflectors for the various 4-strokes.

Failing that, a permanent no-burn solution would be to get a suitable length of stainless steel tubing swaged to fit the existing exhaust outlet and bent as needed.

You can snag stainless tubing at Hobby Town, for example. K&S "metal center" displays include stainless in various sizes and lengths. You can also order the stuff on-line.

A refrigeration service tech should have a bender and a swaging tool. I can do it, if you're near hotLanta.

I will be doing exactly that for my Pegasus . . . using stainless tubing to fabricate a scale L-4 exhaust system. Cheers, Fred McClellan The House Of Balsa Dust home.mindspring.com/~the-plumber

Reply to
Fred McClellan

Brass tubing also works. I have made exhaust pipe extensions for OS

4-strokes which fit tightly over the end of the muffler. You can drill and tap for a small screw to hold it in place. But, for the smaller engines, a press fit seems to hold. In many cases, no bending will be needed. Just adding an exhaust pipe gets the residue out of the way.

Jim - AMA 501383

Reply to
James D Jones

Didn't think brass would like the temperature of 4-stroke exhaust.

Maybe try that instead of stainless; lots easier to bend and fit up.

There will be a good bit of bending needed to duplicate the scale L-4 exhaust system.

I'll post photos on my web site when it's done. Cheers, Fred McClellan The House Of Balsa Dust home.mindspring.com/~the-plumber

Reply to
Fred McClellan

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