Print

[Roger2561]

Hi all - I have a Stihl FS-56 weedwacker.  It's about 20 years old.  Last season I had trouble keeping the thing running no matter what I tried.  With lawn mowing season upon us I decided that I would clean and rebuild the carb and change the spark plug to see if I can get her going again.  I did this yesterday (week off from work).  Now I cannot get the darned thing running long enough to make any carb adjustments.  It'll run on full choke for about 2 to 3 seconds and then quit.  The only time it'll start again is on full choke, but again only for a couple of seconds.  I've tried making adjustments to the carb, again, nothing seems to work.  This is the first time in my life running equipment that I cannot get it running after a thorough carb cleaning and rebuild.  Other than tossing it in the trash and buying a new one, can you offer any suggestions that I can try?  Thanks.  Roger

[slimjim]

I would bet that somewhere in the carb there is an issue with ethanol.

[Roger2561]

After I had disassembled everything I had sprayed some carb cleaner through everything then followed up with compressed air.  Everything "appeared" to be clean, by the naked eye.  I tried finding a new carb for this thing online and dang, those things are pricey!  They range from $70.00 to $110.00 for a new one!  That's crazy!  Twenty years ago we paid $140.00 for the thing brand new!  I think I'll try fiddling with it again today for a bit and if I don't get anywhere with it, I think I'll toss from the roof of the house and use it for skeet practice and then by a new one.  It is 20 years old after all and it owes me nothing and it's not worth the frustration of trying to get it going.  Roger   

[Crow]

 Check the exhaust for a spark arrestor screen. We have a Stihl leaf blower that will start but bog down when you try to run it wide open. The screen on the outlet of the muffler plugs up with carbon.

[hondaracer2oo4]

Sounds like your impulse diaphragm cover is on upside down on the bottom of the carb. They will only run on choke if you put this plate on backwards. The indent should be to the outside(allows the diaphragm to pulse in and out to draw the fuel). If this is installed correctly then get down to your local parts store and pick up a one gallon can of carb dip. It comes with a tray to dip the carb into the can. Let the carb soak for about 20 minutes(tread lightly if there are any plastic pieces left on the carb this stuff is strong). After that blow the passages out with a rubber tipped compressor low gun. The rubber top seals around the jet opening and clears much better than a metal tipped gun. Lastly I know it sucks but a new carb is on the plate if this stuff doesn't work. The little weedwacker and chainsaw carbs don't do well with any debris in the passages because they are so small. You'll be amazed how well it runs with a new carb.

[mlappin]

If you have access to an ultra sonic cleaner try that. I picked one up a few years ago specifically for those pissy little carbs used on small engines.

[Roger2561]

When I went out to try starting it again first thing this morning, after a few pulls on the rope I noticed fuel leaking from where the fuel line enters the carb.  After close inspection I found a pin hole, but not in the rubber fuel line.  The hole is in the plastic piece that the rubber line connects to before joining a brass piece that's pressed into the carb.  Unfortunately, all of the small engine shops in my area are closed for the holiday weekend so I'm unable to get a new one until they open on Tuesday, if they can get the part.  I'm quite sure that the hole in the line is the culprit, but I cannot rule out that ethanol may be a contributing factor too. 

I remember when I purchased my first Stihl chainsaw in th earlier '80's.  It's was an 031.  I don't have it anymore, I let my nephew have it when I purchased the MS311.  My brothers and I would help our dad buck up the year's supply of firewood.  If the chainsaw started acting up, you'd tear into it where you were, fix the problem and get back to work.  It was a simple procedure.  We never had to worry about soaking the carb or using an ultrasonic cleaner on it.  The carb cleaner in a spray can along with a portable compressed air tank was all it took to get you going again.  Oh, word of wisdom - If you're using one of those spray cans of carb cleaner, make sure the exit port on the carb is not facing toward your face, you'll get a face full of the stuff.  Don't ask me how I know this just take my word for it (man, that stuff is cold )    Roger     

[Smokeless]

Roger  if it runs for a 20 seconds and quits. I had one with the piston ring stuck to the piston. Had compression when cold. But less when it warmed up. Not enough to keep it going. Should be able to see it with the exhaust off. Mine is a echo.

[Roger2561]

Roger  if it runs for a 20 seconds and quits. I had one with the piston ring stuck to the piston. Had compression when cold. But less when it warmed up. Not enough to keep it going. Should be able to see it with the exhaust off. Mine is a echo.

Smokeless - I can't keep it running any longer than 2 to 3 seconds tops.  Someone in another forum mentioned the spark arrestor.  I'll have a look later this week when I have a few minutes to get frustrated again.  But that hole cannot be helping matters any.  Does anyone know if super glue will work in an area where there is fuel?  After many google searches I cannot find that part anywhere.  It's obvious that it's something that's not readily available at any shop or online places.  Question - I should know the answer to this; what's the purpose of the welch plugs?  Roger   

[BIG AL]

I think I would go with the throw it off the roof idea. 20 years of service is pretty good for any small power equipment (about 19 more than you get out of the cheep weed eaters from the box stores). I bought a new stihl trimmer a couple years ago to replace my old one and you won't believe how different the new ones are. They are quiet , powerful and easy to start and the auto feed heads work really well. Give the old one to someone who needs it and wants to tinker with it before they use it for a hammer 

[hondaracer2oo4]

If this is a plastic piece attached to te carb( not sure what it is without a pic) than no it is only available as a carb assembly. If it is some other part than yes you can get it but only through a dealer. The gas tank Needs to be pressurized. If there is a hole in either hose than it will only run or a few seconds before it fuel starves. I like some of the older stuff like weed eaters. Chainsaws are different, the newer ones have some good technology in them(I'm talking the $500 plus dollar saws).

[Roger2561]

Right now the thought of using it either as a hammer or simply tossing it from the roof to use as a skeet target are strong thoughts.  I'm going to try to some super glue to see if I can close that hole.  If not, it'll be time for a new one. 

Let's not forget those who gave the ultimate sacrifice for our country tomorrow.  As the words to the song says; "All gave some, but some gave all".  We shall forever be in their debt.  If you want to see something sobering, heartbreaking, etc... watch a UTube video of fallen soldiers being returned home to their loved ones.  I guarantee you'll be moved one way or another.  Roger 

[NaturallyAspirated]

https://www.amazon.com/HIPA-Carburetor-Primer-KN56RC-Trimmer/dp/B0181S1PKG/ref=sr_1_1?ie=UTF8&qid=1496330898&sr=8-1&keywords=Stihl+FS-56+carb

 $30.99

I just got one for my MM55 for $14.99  God Bless China...

Neal