Small Engine Exhaust Question

[cwarrix]

I have a 18HP B&S engine that was part of an old Craftsman riding mower. I'm using it on a log splitter now.

My question is, can I extend the exhaust pipe or muffler to make it more quiet and to get it farther away from the operator without doing damage to the engine? Any ideas would be appreciated.

Some ideas I was kicking around include converting it to a bigger pipe size and using a tractor type muffler, pointing it up in the air like a tractor to divert the sound, and just using a long pipe to route the exhaust out the back of the machine with or without a muffler.

Thoughts?????

 

[JerryG]

As long as the pipe isn't smaller than the original pipe you should be fine. It should make it some quieter with the longer pipe only, but a bigger muffler will drop the noise even more.

 

[cwarrix]

Thanks JerryG, so I could adapt it to something like a universal tractor muffler or an old 8N/9N exhaust and that would be ok? Icould route it down and out the back away from the person running it.

 

[slowrev]

Should work, just be careful about making a rain catcher that will route water into your engine.

 

[JerryG]

I don't think that I would go to awful big. The reason is that if the muffler is to large the air going through won't go in and out the baffles the way it should and it wouldn't be as quite as it should be. If it is to big it would be more like a straight pipe. This is my view only.

 

[FOURTEEN]

My 14hp Kohler had a salt shaker type muffler that was very annoying coming out the side of the engine. I replaced it by screwing in a 3/4" galvanized water pipe 3" long, then a 3/4" 90 to turn it up, then 3" of 3/4", then a 3/4" to 1-1/2" reducer, then 30" of 1-1/2" pipe, then 1-1/2" to 3/4" reducer, then 6" of 3/4", topped with a Clapper to keep the rain out.

It has a nice sound, quieter and mellower than the original, and the exhaust blows up and away.

If you just use a larger pipe it will amplify the sound. All same size pipe won't quiet it much. By using the large pipe between two small pipes, the exhaust pulses can expand to dampen the pressure waves and flow smoothly and quietly out the small pipe.

Also sturdy, inexpensive, and kinda /forums/images/graemlins/cool.gif!!

 

[cwarrix]

Hey FOURTEEN, that is kind of cool! I might have to try something like that. I might go down and out the back of the rig instead of up though. I don't want to be knocking it off with tree branches while I'm pulling it around. I like that idea though, and it will probably last a lifetime too /forums/images/graemlins/smile.gif

Thanks!
Chuck

 

[Schultz]

I made a new low tone muffler for my 5hp B&S rototiller last year that made it much quieter than the salt shaker muffler it had.

What I did was take some expanded metal mesh and roll it into somewhat of a 1" circle tube about 6" long. I had some SS sheet metal that I folded into two pieces to make a 3 x 3 x 7" long box. Then I welded the mesh tube in the center of the box and packed the extra area with fiber glass muffler packing (got it from a motorcycle shop). Then I welded all the seems together and bolted it on the engine.

It was a few hours of work and about $15 in fiberglass packing, but it's nice and quite now since the previous muffler was pretty much rotted out.

Tim

 

[cwarrix]

Thanks for the idea Schultz, I just got the motor off the log splitter the other day. I forgot to mention it is a two cylinder /forums/images/graemlins/blush.gif Maybe I'll make a custom dual exhaust for it /forums/images/graemlins/grin.gif /forums/images/graemlins/cool.gif Dual stacks maybe /forums/images/graemlins/smile.gif

I attached a picture of the motor and half of the splitter. You can't see the exhaust, but it has a pipe that connects both cylinders and then goes into a muffler. I'll try to get a picture of it next time I'm out at the barn. Probably tomorrow /forums/images/graemlins/smile.gif

 

[cwarrix]

Oops forgot the picture /forums/images/graemlins/blush.gif

If anyone is interested, and I know this is a bit off topic, but what the heck, what I plane to do with this is move the motor around about where that silly old tractor seat is. Basically flip it around so you can get to all of the controls from one spot. I was also planning to lower it a few inches. The guy that built this thing put it way up on those stilts, so it doesn't seem sturdy. Well they weren't, I knocked them all off with a small 3lb hammer /forums/images/graemlins/smile.gif I have a new hydraulic reservoir and a new valve to add to it as well. Just something to kill time on right now. I thought I'd ask about the exhaust since this thing is kind of loud. Would be nice to quiet it down a bit.