Stihl FS80AVE w/TK carb won't run

Reply

  #1  
Old 05-26-08, 09:56 AM
Member
Thread Starter
Join Date: Apr 2008
Posts: 4
Stihl FS80AVE w/TK carb won't run

Howdy all,

I have a Stihl fs80 AVE that seems to be in good shape except that the carb doesn't seem to be giving it enough fuel. It will run if I keep pumping the primer bulb, but dies soon after I stop. I don't notice it speeding up when it runs out of fuel like my chainsaw does. I have had it apart twice and cleaned it with carb cleaner. I didn't think to check the settings of the adjustment screws when I removed them (OOPS!), but I think I got them fairly close to where they were. The latest developement is that I can get it to run at higher rpm if I keep pumping the throttle gently. If I run it at wide open throttle, it warbles up and down from WOT almost to idle and back to WOT. Eventually it just quits. Weirdest thing I've ever seen, but I'm not a small engine mechanic.

Do I need to clean it again? Or does it just need to be adjusted? If I really can't get it to work, is there another carb that I can adapt to this engine? Any comments?

Thanks, Guy
 
Sponsored Links
  #2  
Old 05-26-08, 08:13 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,815
Those symptoms could be from a few problems. I would start by taking out the spark arrestor and make sure it;s clean. Then make sure the fuel lines and primer don't have a pinhole or crack in them. Then make sure the fuel filter is ok. Then move back to the carb, and clean it and install a rebuild kit, not just the old gaskets and stiff diaphragms. If the problem persists after this, post back and we'll continue.
 
  #3  
Old 05-26-08, 09:57 PM
Member
Thread Starter
Join Date: Apr 2008
Posts: 4
Thanks for the reply.

I have already replaced the fuel lines, as well as the pick-up in the tank (which I believe includes the filter), and the primer bulb. All were garbage when I got the machine. I will check the spark arrester as soon as I get a chance. I have noticed that there is some air coming up the fuel line when I use the primer - will have to look into that.

Last but not least; I tried to get a rebuild kit from a local Stihl dealer. He couldn't figure out which one I needed over the phone, so I took the whole power head in to him to see. When he came out from the back he had a flyer in hand, so I knew (thanks to another poster on this forum) that he was going to give me the " I don't know why you kept this so long, you should buy a new one" routine.

So... where do you guys find a kit for this?

Thanks, Guy
 
  #4  
Old 05-28-08, 12:32 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,815
It should be a common kit for zama or walbro carbs, not just stihl. Most small engine shops should have a kit, or be able to get you one based on the numbers on the carburetor.
 
  #5  
Old 05-28-08, 04:36 AM
Member
Join Date: Nov 2007
Posts: 128
You have an "Old" FS80, most Stihl dealers, and most
lawn mower shops, have no idea there was an old one.

It is a Japanese trimmer, and is very like the Shindaiwa
T25 trimmer, and is also equipped with the TK carb.

Any mower shop can order you a kit, as the aftermarket suppliers have them. If you still have trouble getting one, let me know.
 
  #6  
Old 05-28-08, 11:22 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,815
I missed the obvious..."TK carb" stated in the title of the thread. Thanks Fish....
 
  #7  
Old 07-18-08, 09:12 PM
Member
Thread Starter
Join Date: Apr 2008
Posts: 4
Back, finally

I meant to get back sooner, but I have been so busy I couldn't even look at my machine. Finally got to it. So I took off the spark arrestor (also called a muffler) and discovered it had a lot of fuel in it. So the carb is overfueling the engine. I tried to start it with the muffler off and saw droplets coming out the exhaust. I was able to get it to run a little bit if I pulled on it with the throttle wide open. Still didn't run well.

So I took it apart to see what I could see. Unfortunatly, when I opened it up, I removed the jet without backing off the mixture needle. Great way to ruin two parts at once - the needle strips the thread on the jet, and the thread on the jet carves up the tip of the needle (both are brass). After cleaning the brass bits out, I reassembled and tried it - now it is completely dead.

I'm at the point where if I can't find a different carb quickly, I'll just have to get another machine.

Any ideas?

Guy
 
  #8  
Old 07-19-08, 10:10 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,815
Ebay? Many small engine shops have 2-stroke junk piles for donor parts. Maybe you could get lucky that way? Ebay or a google search is probably going to be the most resulting effort.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes