Stihl 009-012 Fuel Line trivia question

[rallen]

I am replacing fuel and vent lines on these saws and wondered whether I can use Tygon fuel hoses instead of the Stihl formed hoses. On these saws, the fuel line passes through a 3/16" diameter hole into the carburetor air box. Tygon makes 3/16" OD hose in two different ID's: 3/32" and 1/8". I used the 3/32" ID on my 009 and it appeared to work, but in talking with my local Stihl dealer he recommended I use the Stihl formed hose so it won't collapse.

The original hose appeared to be something other than tygon; it was black and thin, while the fuel tank vent line seems to be vinyl hose.

Any thoughts? Can I use the tygon hose? and if so, the thick or thin wall? The existing hose is soft and I am pretty sure the culprit for the 012 dying out at WOT and then cycling back up, as if it is collapsing.

 

[ZeroJunk]

I use the Stihl gas line because the sizes of Tygon I usually keep won't seal the tank. If you have Tygon that will seal the tank it will work fine.

I don't think it makes much difference what you use on the vent line as long as it sort of matches the hole going out of the carburetor housing.

 

[rallen]

I use the Stihl gas line because the sizes of Tygon I usually keep won't seal the tank. If you have Tygon that will seal the tank it will work fine.

I don't think it makes much difference what you use on the vent line as long as it sort of matches the hole going out of the carburetor housing.

Yes but thick or thin wall, or does it matter? Is 3/32 ID enough to get the gas through, or is 1/8 better but won't collapse?

 

[ZeroJunk]

3/32 will be fine. It won't collapse any proper gas line unless it has gotten rubbery from ethanol or is just old.

 

[galde]

I keep a collection of plastic (teflon, nylon, whatever...) or thin-walled brass or stainless tubing pieces that I save from spray cans, spray bottles, etc.. If I need a fuel or oil line to seal at a hole through a tank there is a size that when a short length is inserted into the line the line is expanded for a good seal. I prefer thin-walled Tygon tubing because of its flexibility, especially for the fuel sinker. Rubber can get soft and squishy enough to collapse, but Tygon won't -- it might get stiff instead. I can buy a roll of Tygon for what some rubber lines cost.