# Stihl FS55RC cuts out at high RPM's



## luckyvision (May 24, 2007)

here is the story:

weedeater is 18 months old, i bought it from a neighbor.

when warm if you hold it WOT, after a few seconds the ignition totaly dies. not sputters, not runs rough, just dead.

he had a no start condition just before i bought it from him, & the shop replaced the coil & plug (plug at his request after they had it running)

the unit will restart everytime, & run at low & mid rpm just fine, but if you hit the throttle too far, *POOF* it dies.

gradually though it'll cut out at a lower & lower rpm 'till it just won't start.

today is the first day i've used it (family is comming, i had to get the yard done) and when it finnaly wouldn't restart, i went & got my shoulda been dead years ago homelite & finished up. i did not have time to go back to the Stihl & retry it after it cooled off.

i plan on checking the kill wire first. i'm also wondering if either the ign they put in could be faulty (electrical components never surprise me) or could an incorrect gap do this?

Thanks, --Lucky


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## hankster (Jan 1, 1998)

Could be fuel starvation. Try opening the high end needle on the carb 1/4 turn.


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## luckyvision (May 24, 2007)

forgot to mention, that was the first thing i tried.

I could be wrong, but it really acts like i flipped the cut-off switch. it feels so ignition... ya know, i'll bet that switch is bad or the wire is grounding somehow...


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## hankster (Jan 1, 1998)

Could be but fuel starvation can act the same. Get a spark tester and hook it between the plug wire and plug... start it and when it cuts out see if you are losing spark.

My reasons for thinking this.. it always starts and runs at low/med RPM and keeps running when RPM drops again.

Ground in wiring is generally random... will happen at all RPMs and at different times.


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## luckyvision (May 24, 2007)

i'll try the spark tester, i've got one, but it won't 'catch' again if i let off the throttle though, once it dies, it dies....


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