Stihl FS46 Trimmer Carb Problems??

   / Stihl FS46 Trimmer Carb Problems?? #1  

dreamen

New member
Joined
Dec 30, 2011
Messages
17
Tractor
john deere LX178 & LX277
I picked up a trimmer for cheap and now I can see why. I can get it to fire and run but its like it runs out of gas. I choke it before it dies and runs good then quits. So I bought a carb kit, cleaned everything, blew out all the jets but there is no high or low speed adj?? There is one larger screw that has a left hand thread, it is not a needle valve as it does not have a point on it, end is about1/8" and has a blunt end on it. Carb is clean and it still does the same thing. Hard to believe there is no adj other than that one screw. Any suggestions?
Thanks
 
   / Stihl FS46 Trimmer Carb Problems?? #2  
You might not want to hear this, but I was in my buddy's shop this morning, and a man brought in a Stihl weedeeater like yours that would not run. Kris is a Stihl dealer, and he grabbed a new carb and replaced it. He saidconsidering the cost of a new carb, he just replaces them in the cheaper equipment-and he is not a man who takes advantage of his customers.

Will
 
   / Stihl FS46 Trimmer Carb Problems?? #3  
he just replaces them

Which is what I'd do if it happened to mine. Several years ago, I paid $40 parts and labor to have a Briggs & Stratton carb overhauled. A short time later, I had a carb problem with another Briggs & Stratton engine I owned at the time. I just bought a new carb for about $40; only took a few minutes to put it on and didn't have to take the machine to town and leave it to be worked on.
 
   / Stihl FS46 Trimmer Carb Problems?? #4  
I picked up a trimmer for cheap and now I can see why. I can get it to fire and run but its like it runs out of gas. I choke it before it dies and runs good then quits. So I bought a carb kit, cleaned everything, blew out all the jets but there is no high or low speed adj?? There is one larger screw that has a left hand thread, it is not a needle valve as it does not have a point on it, end is about1/8" and has a blunt end on it. Carb is clean and it still does the same thing. Hard to believe there is no adj other than that one screw. Any suggestions?
Thanks

Are you sure? The past few years the manufacturers, because of the green laws, have made it more and more difficult to adjust the low and high setting needles. The claim is everybody runs them too rich and causes more air pollution. At least that is what I was told.
I purchased a new pole saw a couple years ago that ran fine for 2 tanks then started acting exactly as you described. I found a couple very small recessed shafts that were knurled on the ends for about 1/4 inch but no slots of any kind and no space for any kind of plier to reach them.
I called the dealer and he said I would have to burn 2 gallon of gas in my car to bring it in so he could adjust it with a special tool.
I asked where I could buy such a tool. He said it had just been made illegal for him to sell them anymore but suggested I look on the net as they might still be available for a couple bucks on there. No luck, so I had to think:)
Looking through a jar of crimp on wire tab terminals with plastic insulation on the incoming end provided the perfect answer. The saw now runs great in all positions.
As a secondary note, I looked at some new chain saws later and one had absolutely no adjustment except idle speed... No sale.
 
   / Stihl FS46 Trimmer Carb Problems??
  • Thread Starter
#5  
Yes, I was surprised to see no adj?? I see a H and L embossed on the carb body but no screws. They must of made them for a while for this model. I found a new carb on Ebay they now all come with a high and low adj for $28. The question is it worth it. It is a used trimmer. Already have $10 for the Trimmer and $8 for the carb kit and I am about at what the thing is worth with a new carb? I have a 2 year old straight shaft stihl brush cutter and it has carb adj. Not sure the age of the FS46
 
   / Stihl FS46 Trimmer Carb Problems?? #6  
Yes, I was surprised to see no adj?? I see a H and L embossed on the carb body but no screws. They must of made them for a while for this model. I found a new carb on Ebay they now all come with a high and low adj for $28. The question is it worth it. It is a used trimmer. Already have $10 for the Trimmer and $8 for the carb kit and I am about at what the thing is worth with a new carb? I have a 2 year old straight shaft stihl brush cutter and it has carb adj. Not sure the age of the FS46

Can you find an exploded view diagram of the carb?
You may or may not be old enough to remember the way the adjustment needles progressed on automobile carbs? They went from flimsy plastic caps to buttons that had to be drilled out to get to the screws.
I'm not saying your carb is this way but sounds suspicious.
There should be a small engine forum somewhere on the net that covers this topic.
 
 
Top