pcjohnson_ohio

I know this has been done a lot, but I thought this works well, is easy, and cheap
(This was inspired by efforts by mikenlapaz)

Weight is 5 oz.
$10 buys enough aluminum to do 4 mufflers
Simple to build, with hand tools only

A little louder than stock ryobi muffler, but no worse than a typical chainsaw
Turns 7000 rpm on MA Classic 18x8 (single ring ryobi, circa 95)
(Have not directly compared to stock muffler, which will not fit on my motor mount)

I will post details if anyone is interested

Pete Johnson

av8tor1977

My Feedback: (6)

Well that's pretty neat. Nice job. I may have to try that.

AV8TOR

av8tor1977

My Feedback: (6)

More comments after actually down loading the pics.

At first I thought the "tubing" in the middle was actually that; tubing for compressive purposes, and I wondered why it did not go all the way from vertical stack to vertical stack. But after studying it for a moment I realized they were probably just threaded connectors... right?

Also, why not carefully spread some JB Weld at the junctions to prevent leakage?

Very nice looking,
AV8TOR

pcjohnson_ohio

Thanks

Yes, those are just threaded aluminum couplers
I planned on closing up the gaps with JB weld and maybe pop riviting the corners
but this works fine, doesn't leak noticeably, and can be disassembled if need be
The flat head bolts seat against the hole

Pete Johnson

w8ye

My Feedback: (16)

The bolts that hold the muffler to the engine will squeeze the aluminum together and the muffler will get lose. Cut some aluminum tubing the right length to fit over the screw part inside the muffler so the bolt heads will have something solid to snug up to.

Enjoy,

Jim

pcjohnson_ohio

If you mean the bolts that thread into the holes next to the exhaust port
I already did that, if you look close in the center picture, you'll see 'em

Pete

airbr

My Feedback: (4)

Very good idea, It will work for a poor man like myself whom is in love with the hobby.

w8ye

My Feedback: (16)

Sorry about not being able to tell for sure about the internal support tubes. At least we got the point across that this needs to be done? Good job.

Enjoy,

Jim

JPALPHA

My Feedback: (1)

Very good idea & good job!

What is the square tube under the exhaust port square tube work for?
Is the 2 square tubes internal connected?
Could you post detail construction?

Thanks for sharing the good idea

JP

pcjohnson_ohio

The tubes are 1" and 3/4" square 1/16" walled aluminum tubing, 4" long
The two 3/4" tubes are side by side with 1/2" holes (two of them) connecting them
This was done to increase the chamber size of the muffler as well as make the assembly more rigid

The 1" side tubes have 3/4" x 1 1/2" square holes in the side to accept the 3/4" tubes
These were done by drilling a series of 1/4" holes to remove the bulk of material and then enlarging the hole with a coarse file
The fit of these holes is very tight

The 1/16" gap between the tubes (inside the side tubes) is filled with 1/16" fiber gasket material
This is shown in gray in the diagram
These are inserted from the end of the side tubes, prior to assembly

The whole thing is held together with long bolts and locktite
Not shown in the diagram but mentioned in the previous post is the 5/8" x 1/4" hollow spacers around the mounting bolts which support the muffler when you tighten the bolts that hold the muffler to the engine.

I hope this is clear

Pete

mikenlapaz

pcjohnson_ohio
Mikey Likes It!
A definite improvement in square tube exhaust deflectors. My experience with JB on mufflers is a limited but I think I will try some red RTV sealant between the two 'chamber pieces"

Nice Job and drawing.

gtisme

Pete,

Great information, excellent worK! Thanks for sharing your work with the rest of us.

Gary

pcjohnson_ohio

Thanks to all
I tried to find Mike's old post, never did
Call me cheap but there is something appealing about a $5 muffler that works and looks good (I think it does anyway)

Pete