SuzukiSavage.com - Print Page

SuzukiSavage.com
/cgi-bin/YaBB.pl
General Category >> Rubber Side Down! >> Question about exhaust leak backfire
/cgi-bin/YaBB.pl?num=1162864444

Message started by Steve530 on 11/06/06 at 17:54:04

Title: Question about exhaust leak backfire
Post by Steve530 on 11/06/06 at 17:54:04

I've read that even a small exhaust leak will cause a backfire.

Does anyone know why this happens? In other words, how does the leak cause the backfire?

Title: Re: Question about exhaust leak backfire
Post by Reelthing on 11/06/06 at 18:00:32

let's it suck fresh air as the exhaust goes out the pipe - real lean/hot bang it goes

Title: Re: Question about exhaust leak backfire
Post by Steve530 on 11/06/06 at 18:19:36

So fresh air enters the leak, leans the exhaust mixture even more, and any remaining gas accumulates and eventually fires?

Something like that?

Title: Re: Question about exhaust leak backfire
Post by Reelthing on 11/06/06 at 18:36:24

that's my understanding of a leak backfire - a very rich one can happen as well with fire running out the pipe - where you get raw fuel puddle in the muffler, or course the best ones are from a missing engine - no spark for a few rotations and you get a very nice mixture in the pipe and then a good spark - whooo boy you can get one that blows things apart - saw one like that in a motorhome a buddy had - the hot on his battery bank had shorted against the frame rail so most all the juice was gone - he hit the electric starter on the aux generator well it kill the 440ci engine as soon as he let up on the button the engine fire back up - blew the muffler in half on the winbago

Title: Re: Question about exhaust leak backfire
Post by Steve530 on 11/06/06 at 21:44:16

The carb on my lawn tractor started leaking. I figured the needle valve was leaking. I replaced the it and the float twice. Finally got enough gas in the muffler to blow it off. That was exciting enough. I ended up buying a new carb and a new muffler, too.

Anyway, guess I need to check that Dyna muffler on the Savage again. I noticed some soot on the frame and engine case near the muffler adapter. Could be happening during the shutdown backfire. Must be an opening there any way you look at it.