# !4 HP B/S backfire



## TomF1 (Nov 15, 2004)

*14 HP B/S backfire*

I attemped to start my mower, the air temp 65 degs, the engine was cold, it backfired,and has been a cranking more than usuall now to start. Normally before the back fire it cranked over about 3 times and fired up.

B/S Model 280HO7 Type 0166E1 1 yr old


The owners manual says to shut the engine off at full throttle to prevent back fire which I do.

Could the headgasket have blown when the backfire occured, its runs great when its running plenty of power, or the crankshaft ket sheared slightly to throw off the timing?




TIA

Tom


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## roperdude91 (Nov 10, 2004)

TomF1 said:


> I attemped to start my mower, the air temp 65 degs, the engine was cold, it backfired,and has been a cranking more than usuall now to start. Normally before the back fire it cranked over about 3 times and fired up.
> 
> B/S Model 280HO7 Type 0166E1 1 yr old
> 
> ...


i have a briggs 4hp quantum that backfires through the carb, shop said thevalves needed to be replaced :tongue: 
had em replaced still did it, turned out the cam lobes were screwed up, warped and out of whatever lol

i have a honda gcv160 that the valves are sticking on to the point that alot of the times you try to start it or run it at a low idle it backfires through the muffler an carb at the same time and sometimes just through the muffler, qwhen its just through the muffler, there is a 2 to 3 foot flame to go with it  
i seriously need to hold onto my money and get enough to rebui;ld that thing, i majorly screwed up on the carb work today, i set the idle speed so high u can tell is its at ull or idle unless you look at the throttle lever

i dont know if its running rich or not it just dont smoke unless u put it under a big load or you choke it
still could be carbon fouling the plug again, i hope not, it hasnt ran right for years, maybe its cuz it has over 1000 hours on it and most of its mulching feild grass


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## bugman (Aug 12, 2004)

turn the needle valve 1/8 turn counterclockwise for easy starting in the cold. my 12 horse does the same thing but really it isn't nothing to worry about. everything checks out on mine its just the cold and if it was used alot it'll do it


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