shutting off your lazer

[scott's turf]

When you shut off your lazer do you thottle down first. I was doing this but found that when I did shut it off the machine would always backfire. What do you guys do?

[65hoss]

I was having the same problem with mine in the past. Here is what I started doing...

When I load on the trailer I turn the fuel to the off position. I let it run itself out. This does 2 thing, 1st it doesn't backfire anymore. Secondly, it allows the motor to cool down before shutoff. Air cooled motors get their cooling from running. Let it go at idle while the fuel is running out and it gets less friction, air is moving, oil is moving, all of which helps cool the motor.

[SIG]

If you guys have Kohlers, read your owners manual. You should shut the mower down in 3/4 throttle position. Will eliminate the backfire and run-on problem. It's right there in the owners manual.

[Pro-Cut Lawns]

I load mine on the trailer when Im finished, leave it idling, put up the gate, start my trimmer, then shut the mower down. Once it idles in that amount of time before shutting it off it wont back fire. I would rather do that than shut it down at 3/4 throttle.

[bubble boy]

hoss, is that at full throttle? i have a toro with a kawi engine(12 HP? i don't know off hand) that will backfire unless i throttle down before shut off. i never tried what you're saying, but i would have thought letting the fuel line drain at full throttle would still result in the back fire, since the engine is still going pretty strong.

is this normal? doesn't happen on our ferris with the kawi.

and is it harmful to the engine?

[65hoss]

Originally posted by 65hoss
I was having the same problem with mine in the past. Here is what I started doing...

When I load on the trailer I turn the fuel to the off position. I let it run itself out. This does 2 thing, 1st it doesn't backfire anymore. Secondly, it allows the motor to cool down before shutoff. Air cooled motors get their cooling from running. Let it go at idle while the fuel is running out and it gets less friction, air is moving, oil is moving, all of which helps cool the motor.

At idle.

[AltaLawnCare]

After I unload, I always close the gate on the trailer. So when getting ready to load,..
I idle down,
Set the parking brake,
Turn off the fuel,
Get off and lower the gate, fold over the discharge chute,
Idle up to 3/4 throttle, drive up on the trailer,
Lower the deck all the way down, idle down to 1/2 throttle,
Set the brake, then shut it off.
:p

[scott's turf]

I have a 23 hp kaw. Hoss when you do this do you have to choke it to start it at every job? What damaged is cause by shutting off a hot engine? Is it going to cool to quickly and cause a thermal contraction problem?

[Runner]

With the 20 hp Kohler Magnum, I would always let it idle down for a minute or so while I did the gate and such. Otherwise, it wouldn't backfire when I shut it off, but when I would start it back up again. Even after it sat for awhile. With the Command though, I just idle it down for a few seconds and shut it off. It's fuel injected, so there isn't really any difference.

[65hoss]

Originally posted by scott's turf
I have a 23 hp kaw. Hoss when you do this do you have to choke it to start it at every job? What damaged is cause by shutting off a hot engine? Is it going to cool to quickly and cause a thermal contraction problem?

That is the same motor I have. Yes, you choke it at the next job. Fires right back up.
The 1st thing that an air cooled motor does when you shut it off is increase the heat. It gets hotter before it cools down. Nature of metal. It doesn't hurt anything, because it doesn't cool down that much.

[scott's turf]

If it doesn't hurt anything why not just shut it off at full thottle?

[65hoss]

Originally posted by 65hoss
I was having the same problem with mine in the past. Here is what I started doing...

When I load on the trailer I turn the fuel to the off position. I let it run itself out. This does 2 thing, 1st it doesn't backfire anymore. Secondly, it allows the motor to cool down before shutoff. Air cooled motors get their cooling from running. Let it go at idle while the fuel is running out and it gets less friction, air is moving, oil is moving, all of which helps cool the motor.


Friction

[chariot]

Noone will believe this but this is what I did. My friends here locally didn't believe me. I had a mower with 25Hp Kohler, it did this backfire thing. To get it to not backfire all I had to do was: Pull the throttle down to idle, turn the key off, as soon as you take your hand off of the key push the throttle back up to wide open. I hope this makes sense, let me know if you try it and it works.