Need info on running with no muffler

[PawNature]

First thanks to all the help I have received from many different folks here on the forum.
The studs on my 13hp exhaust broke off. I know i will need to have them drilled out. Problem is i have some sawing I need to finish. Will running the engine without an exhaust system hurt the engine.

[ADAMINMO]

I don't know this for fact but have heard that it can cause problems due to the fact that on the intake stroke of your engine it is pulling in a cooler air then when it has the exaust on it.I have heard that it can crack the piston or the piston walls due to the cooler air rushing in on a hot piston.With the muffler on there it is pulling hot air on the intake from the exaust.Like I said though I don't know this for fact but have heard it.

[flip]

You can run it for a limited time.  The engine does need some back pressure to keep scavaging going.  The muffler also pulls heat from the head.  I wouldn't cut for more than a few hours at a time though.  And wear your hearing protection

[Burlkraft]

Ain't got no duct tape.... :D :D :D

[PawNature]

Ain't got no duct tape.... :D :D :D

Seems it don't last long with the heat of the exhaust. Super glue doesn't work either.

[scsmith42]

The other issue that you have to be concerned about is if you're running hard w/o a muffler (or exhaust pipe) and you suddenly shut down, a blast of cool air hitting the exhaust valve can warp it.