Stihl Farm Boss

[laynes69]

I have an old Farm Boss Stihl chainsaw that hasn't ran in couple of years or so. I need to clean it up and when I start it, it will idle so high the chain will spin the whole time. Does anyone know the carb settings for one of these, and which screws adjust what? I wish I knew the exact number of the saw, but I do know its a farm boss. Any other suggestions on what to check to get it tuned and going again.

 

[stangds]

does it have 2 screws or three on the side of it?

turn them all in, then out 1 turn. that may be a good place to start. you have to adjust the highspeed until the sound "warbles" (broken link removed to http://www.madsens1.com/sawtune.htm) that site is down right now, but it has some good information on it.

 

[laynes69]

Thanks, Its got 2 screws on the side of the carb.

 

[MALogger]

Look a little closer at the carb, there should be 3 screws.
1 screw is for the idle then there should be 2 screws for the mixture low speed and hi speed

the 2 mixture screws on a stihl should be turned all the way in then backed out 3/4 of a turn as a starting point.

the idle adjustment just positions the butterfly on the carb but that should be set after the 2 mixture screws have been adjusted.

Craig

 

[stangds]

for a while stihl only had 2 screws it was some BS envirnmental crap.

they are back to 3 now, but it's still not as good as the older models, from my understanding. the 2 screw models don't have the high speed adjustment which can lead to some real issues when you are tuned for the mountains and operate at sealevel.

laynes69, one of your screws is low speed adjustment, and the other is idle speed, start with one turn out from all the way in and see where that gets you. if your carb is gunked up pretty bad, it may have to be cleaned up before it will run properly. the chain should not turn when the saw is idling.

make use of that chain brake too while walking around with the saw! a trip to the ER makes for a long day!

 

[ozarkjeep]

if the fast idle is a NEW condition it could indicate an air leak, which could lead to a lean sieze under load.

on my old Stihl, there is a screw labled "LA" that adjusts the idle.

their are manuals available online through stihl as well.

http://www.stihlusa.com/information/info_product2.html

look through and find one similar to your saw, it might be helpful.

 

[laynes69]

The carb was caked up inside. cleaned everything in dawm and reassembled the carb. It starts right up, but I can't get it to idle down. Once I get it set it should cut fine. Its not pouring smoke now. Everything inside was pretty bad. I got the saw from dad, I don't think the carb has been cleaned in years. I have a good air filter and I check the fuel filter in the tank. There isn't a chain brake so I gotta be on top of things.

 

[kevinmoelk]

Check for an air leak as Ozark mentioned. If the saw had been sitting around for a while, chances are gaskets got dried out and are probably no good. You can check for air leaks using standard automotive brake clean. BE CAREFUL, this stuff is highly flamable, use it sparingly and try to figure out where the leak is coming from. Spray it around the base of the carb, over the adjusting screws, etc. Do not spray it on the exhaust. I'd have a fire extinguisher around just in case while doing this, and of course safety glasses. I don't mean to scare you... I've used brake clean spray to find leaks for years as an auto tech, just keep in mind that the operation is indeed dangerous.

Also, how is your gas? If old, get rid of that stuff, put in some fresh with a proper oil mix.

-Kevin

 

[ozarkjeep]

so, did you count the turns on the screws before you dissassembled it?

and set them back to where they were?

The carb was caked up inside. cleaned everything in dawm and reassembled the carb. It starts right up, but I can't get it to idle down. Once I get it set it should cut fine. Its not pouring smoke now. Everything inside was pretty bad. I got the saw from dad, I don't think the carb has been cleaned in years. I have a good air filter and I check the fuel filter in the tank. There isn't a chain brake so I gotta be on top of things.

 

[laynes69]

The screws werent set right in the first place. The spacer or manifold between the carb and the cylinder had a gasket that was blown out, so there was a leak. I took about 5 layers of tar paper and made a new gasket for it. It started right up and I'll have a new tank of gas to run through it to finish setting it. It sounds good now. Thanks for all the help. Just about got it. By the way do you know what size of bar this saw will take? I think its an 041.

 

[kevinmoelk]

Oooooh, I would advise against using tar paper. The tar will melt with the gasoline and break down again, not to mention the possibility of gumming up. Just use some cardboard from the back side of a pad of paper. Or better yet, purchase the proper gasket.

-Kevin

 

[nshif]

I agree with Kevin. This is not a good place for a tar paper gasket. ( I cant think of many that are ) Go to your local auto parts store and get some cork gasket material and a tube of permatex and make a good gasket.

 

[stangds]

gasoline will eat permatex too

 

[nshif]

Not according to permatex.

(broken link removed to http://www.permatex.com/products/automotive/automotiveasketing/gasket_sealants/auto_Permatex_Form-A-Gasket_No_1_Sealant.htm)

 

[elkimmeg]

the Farm boss 041 is a pretty powerfull saw. Mine has a 16" bar I have run 20" ok and even 24" Its a low rpm saw but high tork. Todays saws use higher RPMs
I said I would replace it long ago when it dies 30 more house lots and it still here working as always These old farm bosses were made in Germany and were of highest quality
N0 plastics anywhere

 

[stangds]

I always think 029 when I hear "farm boss", but my dad has an 041 like you are mentioning elk, it's a beast, but it's the pre safety days and has pretty much just sits there these days. his 041 won't hold a candle to my 066, though! (not that it should... )

that particular version of permatex may be OK, but the regular stuff will get ate up in a gasoline envirnment. Read the labels. chapstick on the gaskets is a good idea too

 

[kevinmoelk]

No need to use any permatex whatsoever. If you want to use a sealant, use the red spray type head gasket sealant which will be impervious to gasoline. But as I said, no need for it at all. Don't want to use cork on a gas seal, I almost never use cork... unless specifically called for. Cork is pourous and can leak out unless you use sealant, but you can avoid doing that just by using a different gasket material. Cork is "okay" for valve cover gaskets and oil pans, but again, I'm against them generally speaking.


-Kevin

 

[nshif]

Kevin
I agree again but this is not a liquid seal as i understand it and cork is the most readily available gasket material out there. I was only suggesting the permatex as an assembly aid if he needed multiple layers and to hold it in place.

 

[kevinmoelk]

It doesn't have to be a liquid seal. I didn't want to get into it, but the reason cork is used is to provide breatheability (is that a word?) and designed flexibility. Using cork for a non-cork application is foolish. Engineers know what they are doing, if they wanted a cork gasket there, they would have specified there be one.

Not to mention, cork being a natural product will eventually dry out, crumble and rot. Even when I receive a cork gasket for a valve cover or diff cover I ask if there is an alternative available, that's how much I don't like them. Why not go back to leather and felt seals while we're at it. Because we have better materials that's why!

I've been working on equipment for a long time, and still hold a master technician ASE certification. Trust me guys, no cork, and no sealant. By the way, any auto parts store should have raw gasket material other than cork.

-Kevin

 

[nshif]

Well Ive been out of the business for awhile so Ill concede. Although I do know that all my local auto parts house only has bulk gasket material is cork.

 

[Sandor]

Cereal box cardboard is a good emergency gasket maker.

Cleanliness of the mating surfaces is essential for a good seal.

 

[laynes69]

I'll have to go out and get some gasket material. I needed to see it the gasket was the problem. Which the carb and the gasket was.

 

[kevinmoelk]

Sandor, yes, cereal box can work in a pinch. The only problem there is that there is actually a very thin layer of plastic on the outside of the box. That is why I recommended the cardboard off the back of your standard pad of paper, legal pad, etc. It's usually nice and dense, a nice gauge thickness, and has no plastic covering. But that said, purchasing true gasket material, or replacement gasket, will yeild better results in the long run.
-Kevin

 

[MALogger]

I'm gonna go out on a limb here,
Have you checked with your local stihl dealer for the correct gasket?
even though it is an older saw it might be available or if it isn't the dealer may have the correct material for the gasket as well as some fuel line for that saw.

Craig

 

[drizler]

Gaskets are dirt cheap for anything. I have made em all and never was one of my home rollies as good as a factory gasket period. If you can't find one then go to Advance auto or Autozone or Napa and buy a cheap roll of gasket material that is the right thickness for $4. Its handy to have around.