why x585 backfires when starting

[fbergman]

its fuel injection
didnt do it last fall when put away for winter .

 

[beenthere]

Welcome to TBN
How much backfire? just a pop? or a louder bang? (if that makes sense).

Sounds like fuel mixture.

Did you treat the gas with something like seafoam before storing over winter?

 

[fbergman]

yes seafoam all the time
just a pop

 

[beenthere]

When my fuel injection X485 was newer, I occasionally had a pop on startup. But after running, was ok (no pop).
Recent years, no pop on startup.

Have learned a quicker (better?) start-up routine by turning over the engine for a second or three. Turn key off, then back on start again. Engine fires off in much shorter crank time with this double start plan.
Not sure why, but like it better than grinding away for a "longer time" (ha!, all of 10 seconds).

 

[BravoXray]

Put a new spark plug in it.

 

[ruffdog]

Has the valves been adjusted? If they are getting a bit loose, that can affect the decompression mechanism during startup.

 

[Richard001]

its fuel injection
didnt do it last fall when put away for winter .

Does it start in spite of the backfire ?

 

[big bubba]

Has the valves been adjusted? If they are getting a bit loose, that can affect the decompression mechanism during startup.

agree, esp if it's never been done previously. change the spark as mentioned too (also check if spark temp is within correct specs of engine) are you using non ethanol?