Briggs 18hp backfires on shutoff???

[wheeler]

After driving for awhile, when I shut it off the engine backfires? Any ideas on what to do or what is causing it?

[Bazooo guy]

Before you turn it off let the engine idle for a minute to cool down.

[trevorakm1]

adjust the mixture a little leaner, mine did the same till I adjusted.

[msafi65]

the dash sticker on the newer MAX with carb solonid fuel shut off say to raise engine speed to half throttle before shut down. This makes the engine roll over after shutdown with no fuel and clears the mixture from the hot muffler.This really helps on ones with fuel shut off,not with standard carb.

[jpswift1]

There's nothing wrong with your engine. This is just the nature of Briggs and Stratton Vanguards. You won't really need to adjust anything, it's just how they act. Very often on rides you'll hear a "pop" which is a backfire from one of the 6 wheelers when we all shut our engines off to stop somewhere. That backfire is always followed by someone yelling, "Briggs!".

[wheeler]

I did adjust the idle speed up a bit, as it was idling to slow. Now I get more backfiring on shutoff. I'm going to adjust it back a little again. I've got to find some sort of solution to the backfire. I will be using the Max to deer hunt and I can see it now, I drive to my hunting spot and when I shut it off every deer in the area takes off due to the shotgun backfire I get. I mean this is a real, real loud backfire. But, you are right, I have a briggs on my Zero turn mower and it does the same thing. I'm gonna keep researching to see if I can minimize the backfire.

[wfo]

read the spark plugs see if their white or tan, its a hot lean condition, idle and let it cool before you shut it down like bazooo said

[Bazooo guy]

You could run some seafoam thru the fuel system.
If your carb or jets are not clean or valves are sticky it could cause a lean condition and run hot.
Worn points will change the timing and could also cause the engine to backfire.