Stihl Kombi Motor KM 56 RC-E -Low Power, Won't Idle - Muffler?

[Old fart]

I think it just started, I have been traveling a lot and my bride uses the battery blower/trimmer more when im gone but im sure she used it some. When i was home for a few days after 6 or so weeks is when i noticed it wouldn't idle.

Only think I'm confused about now is why it was necessary all of a sudden to crank up the idle screw. guess it being like 12 years old i couldn't complain much if it blew completely up tomorrow....

Sounds like your carb is varnished up. I will tell you something that is cheap and easy to try and I have had several times when it fixed the problem when it was just varnish in the carb. Go to your local parts store and get a little pint bottle of Lucas fuel treatment. Dump your old gas/oil mix out and mix up some fresh fuel/oil. Add a little of the Lucas fuel treatment to your jug of fuel and don’t be worried about putting to much in. I would use about 1/5th of the pint bottle in a gallon of fuel and mix it good. Now fill up the tank and fire the motor up, just so you get fuel in the passages of the carb and shut it off. Let it set overnight and see what it does the next day. That has fixed my old FS75 a couple of times and a old MS023 that I used to have after they had set a while and varnished the carb.

 

[DuckRyder]

Stihl OEM Carbs are cheap. I'd just pop another on and move on.

It's probably not your oil, but gas that went bad. Happens all the time in small engines that sit with pump gas.

Grab yourself a 5 er of sunoco ultra 95 and get some into each of your small gas devices before the winter, switch back to pump during hard use season.

Sounds like your carb is varnished up. I will tell you something that is cheap and easy to try and I have had several times when it fixed the problem when it was just varnish in the carb. Go to your local parts store and get a little pint bottle of Lucas fuel treatment. Dump your old gas/oil mix out and mix up some fresh fuel/oil. Add a little of the Lucas fuel treatment to your jug of fuel and don’t be worried about putting to much in. I would use about 1/5th of the pint bottle in a gallon of fuel and mix it good. Now fill up the tank and fire the motor up, just so you get fuel in the passages of the carb and shut it off. Let it set overnight and see what it does the next day. That has fixed my old FS75 a couple of times and a old MS023 that I used to have after they had set a while and varnished the carb.

I will look into both, but the reason that i don't suspect the carb so much is that my power equipment runs either canned gas (like theMotoMix) or Ethanol free pump gas.

 

[UncleDave]

I will look into both, but the reason that i don't suspect the carb so much is that my power equipment runs either canned gas (like theMotoMix) or Ethanol free pump gas.

Is the plug nasty?

 

[super20dan]

STIHL ultra IS FOR the 4 mix engines .

 

[DuckRyder]

Update:

It still was not running right, it would idle but had a flat spot and would sometimes "clear out" and run like it old self, then start acting up again. I had already replied the plug as method and i replaced the air filter and the fuel filter. (if you buy a still tune up kit its a fuel filter a plug and an air filter, the fuel and air were original.

Still acted up, so after some difficulty with getting the right carb (it's new enough to have a Zama Carb (not a walbro) but the throttle cable attachment is not like the newer ones) i replaced the carb and it seems to be fixed.

I would not call this carb cheap at 45 bucks though...

 

[jeepman3071]

Update:

It still was not running right, it would idle but had a flat spot and would sometimes "clear out" and run like it old self, then start acting up again. I had already replied the plug as method and i replaced the air filter and the fuel filter. (if you buy a still tune up kit its a fuel filter a plug and an air filter, the fuel and air were original.

Still acted up, so after some difficulty with getting the right carb (it's new enough to have a Zama Carb (not a walbro) but the throttle cable attachment is not like the newer ones) i replaced the carb and it seems to be fixed.

I would not call this carb cheap at 45 bucks though...

They aren't cheap, but I'll always recommend replacing with an OEM carb over a cheap China carb. One of my neighbors had a small Husqvarna chainsaw that wouldn't run right. Turns out he replaced the carb with a cheap China one, and it wouldn't stay in tune. It would run great for one tank of fuel, and then it would bog down and you would have to play with the jet settings (adjustable luckily). Replaced it with an OEM carb and it has been flawless since. The OEM carb was probably $35 more than the cheap Amazon one, but for the amount of time he fiddled with the thing, I'm sure he wished he spent the money for the OEM in the first place.