muffler?

[gws]

I have a 20hp v twin B&S engine on my tractor. Tractor was running fine then all of sudden it got very noisy and VERY fast.
Probably came close to doubling my speed and trippled the noise the tractor made. I shut it off quickly and couldnt find anything wrong. I though I might have poked a hole in the exhaust pipe but cant find any.

I dont see any physical external damage to the mufflers . Do they just let go like that without warning? Does the back pressure slow the tractor that much?

If not any ideas?

 

[Molerj]

I don't think it is the muffler that caused your problem. It sounds more like a governor issue. The governor is what keeps the engine from overspeeding. Could a spring have broken or something else on the linkage have fallen off?

 

[Slamfire]

Make sure the throttle linkage is not binding or overcentering anywhere. A neighbor had his B&S run away while he was off the mower, and the engine threw a rod. Even a governed engine can run away if the linkage is fouled up. /forums/images/graemlins/tongue.gif

 

[slowrev]

I just fixed the neighbors mower last week that had the same problem. His problem turned out to be that throttle plate had fallen off in the carb and it would run wide open.