View Full Version : Whats the deal with the fire flame shooting out of my muffle

05-24-2000, 02:59 PM
Why does a flame shoot out of the pipe of my muffler when i shut it off. Its a new lazer Z? Is this something that will cause problems later? It also will backfire real loud sometimes. Is there something i should do to fix it?<br>thanks<br>Dingo<br>

05-24-2000, 03:06 PM
I'm no help at all when it comes to being a mechanic, but our Exmark 48&quot;'s with Kawi's do the same thing. (Big Bang and Fire show!) Our mechanic says, besides blowing apart the guts of the muffler, it won't do any harm. He told us piston and rings would do the trick, but ours are 10-15 years old. Yours, much newer, I wouldn't understand. Are your dealers any help or do they fit the description of &quot;the rest of them!!) Be carefull!!<br><p>----------<br>&quot;guido&quot;<br>David M. Famiglietti

Richard Martin
05-24-2000, 05:36 PM
Just let the engine idle for a minute or so before shutting it off. When you drop RPMs from 3600 to idle a certain amount of unburned fuel will be in the muffler. If you shut the engine off without removing these unburned fuels the fuel continues to heat up until it ignites. It is also not the best thing in the world to shut the engine off without letting it cool down at idle anyway.

05-24-2000, 06:30 PM
After letting it idle take it back to about half throttle then shut it off. That stoped it on my Kohlers.

05-24-2000, 06:56 PM
They stole your engine from the BATMOBILE :)

05-24-2000, 09:20 PM
Just think of all that money you save on fireworks come the 4th of July

John DiMartino
05-25-2000, 12:43 AM
Dingo-like the others here-I let my kohler idle for about 30 seconds to cool off the exhaust and valves before shutdown.The flame only happens when you shutdown and the throttle and rpms are about 1/2 and at least 2000rpms.As the engine spins to a stop,the mechanical governor tries to bring the rpms back up by opening the throttle,if the engine is spinning fast enough(wound up)at shutdown it will have time to draw a lot of fuel thru the engine,then it stalls.The muffler gets hotter immediately after shutdown,the fuel reaches flashpoint temp in the hot muffler and you have a flame.<p>----------<br>John D<br>

05-25-2000, 12:49 AM
thanks for the responses guys. Im glad i noticed this problem because i use to have my gas cans a litte off the side. now that would have been a real fireworks show.<br>thanks <br> Dingo

05-25-2000, 09:06 AM
THat is a common problem. Throttle up to 1/2 to 3/4 when shutting off.

05-26-2000, 07:41 PM
I put in mobile1 fully synthetic oil Kohler lazer after 135 hours of use. Didnt backfire at all in the first day of use with the new oil.hmmmm

Prime Seasons
05-26-2000, 08:08 PM
Do you have a Kohler engine? Like what was already mentioned, throttle up 2/3 and turn the key to off. As a fluke, the electric solenoid in the carb stays open slightly unless you have throttle in this position. Try this method, out-- I got it from the Kohler Info booth at Louisville's lawn expo...