Stihl MS: 210/230/250 Series - Repair Leaking Fuel Line DIY

Perform chainsaw maintenance at your own risk.

Parts and tools needed:

Stihl fuel pick-up 0000-350-3500
Stihl fuel line 1123-358-7702 (or 1123-358-7701)
Plastic autobody prying tools (Harbor Freight $5)
T27 Torx driver
8mm socket driver

The fuel line becomes brittle with age and exposure to E10 fuel, and will spray fuel out from around the rubber flange where it passes through the tank. The -7701 is used on the Stihl 021, 023 and 025. The -7702 is used on the MS210, MS230 and MS250 saws. The fuel pick-ups vary by model and appear to be somewhat interchangable. Check before ordering.

This is for an MS250:

Look closely at how the square tab on the fuel flange is seated in the square molding on the top of the tank. It will go back on this way:



Remove the filter cover and air filter. Pry out the handle bolt caps:



Remove the 6 T-27 Torx bolts to remove the handle (this is a good time to clean up oil and sawdust):



Remove the 2 8mm filter housing/carbureator nuts and slide off the filter housing:



Note how the cut-off contactor is fitted: the wire fits into the choke lever and the contactor lever rides on top of it. If the springy contactor lever is allowed to slip under the choke lever during reassembly, the cut-off switch won't stop the engine.
Now disconnect and remove the throttle linkage. Unsnap the throttle linkage from the trigger and rotate clockwise to unhook from the carb:



Operate the choke lever to put it in a disconnect/unhook position. In the right position it will unhook easily. Unsnap the choke lever and unhook the choke linkage:



Pull the fuel line off the carbureator:



Note how the tank vent plastic tubes fit over the carb adjustment screws. Slide the carbureator and tank vent off the threaded rods. Insure the carb gasket (still seated in this pic) is still fitted over the threaded rods:



Stihl part numbers for new fuel pick-up: 0000-350-3500 and fuel line: 1123-358-7702:



Reach into tank through filler hole with a small plastic autobody hook and fish the old pick-up out, then remove it.

Caution, don't gouge the tank or fuel line with a screw driver or sharp metal tool. Use only plastic autobody tools (Harbor Freight $5) to pry the fuel line.

Pry old fuel line out of hole in top of tank. Lube the new fuel line flange with 2 stroke oil and insert the curved end first. Work it into the tank with the square-sided tab oriented to the left in the square molding in the tank top (look at the first picture). Try to get the tab correct before the flange seats -- even lubed with 2-stroke oil, it's a #$%^& to turn.

Fish the line out of the tank as before and install new pick-up.

Reassemble in reverse, insuring tank vent tubes are seated over carb adjustment screws, linkages are correct and the springy cut-off contactor lever is lifted on top of the choke lever correctly.

Nicely documented. Will come in handy.

I have an ms250 as well and I like it.

Thats a awesome tutorial lesson.......thanx.....will come in handy..better then reading it from the book.

Thanks for the comments. I've learned so much from sites like this, it's nice to try to give back once in a while.

Yeah, the MS250 is a great little saw. I've used mine extensively for about 5 years with total reliability. So when it finally started spraying fuel on me, I was glad I could fix it for about $13. Good as new.

Very nice write up! Maybe you have inspired some to attemp a fuel line repair on their own and save a bundle. Great Job!

good pictures...

I have been eyeballing that MS 250 for some time now. that one and the farm boss..

might just be day dreaming but I do have a birthday coming up...

That saw doesn't look like it has been use much? Have you been leaving fuel in it?

Moonshine is hard on the lines I'm guessing.

I am running the same shine! 460 was bought early 07 and run the heck out of it, sure does not shine up like that anymore. (not need fuel lines yet)

It's been used extensively. I take care of my equipment. The local Stihl dealer told me the fuel line rubber loses elasticity after enough hot/cold cycles. Additionally, like most locations, I'm stuck with E10 fuel.

It was easy to fix. The MS250 has been a very reliable tool and a huge improvement over my earlier P____n that needed a 22 foot cord to start -- grab the pull handle and throw it off the rooftop. :lol:

Cleanliness, and changing wear items and fluids seems to keep most equipment happy.

Oh nothing wrong with a clean saw but there is things that will show use on a saw no matter how clean you keep them. That is a well cared for saw know dought about that. The discoloring under the sprocket cover will show the use of a saw. Flip the saw over and it will show the use there as well. Just seems very early in the life of that saw to need fuel lines thats all. Nice post just looking for more info on cause. Is this an issue with all the 250's?

the moderators should make a place where these good write ups could be saved as sticky's.
some other forum's i go to do this and is very helpfull.

make a saw maint. sticky.

has my vote

Yes, pic's and details on this is Awesome +1

or maybe not

Thanks for the great thread, I replaced the fuel pipe on my ms 210 using your directions.

Now I have the problem that the silly thing won't start. There is a spark and the plug gets wet if I keep trying to start it, so there is fuel and a spark.

I have very little experience with chain saws and would appreciate some feedback from you guys, in case it might be something simple I am overlooking.

Thanks in advance.

Louis

Hi again

Did a bit more research and was all set to dismantle the carb and expecting to see damaged parts because I had left it over the winter with fuel in it.

I also saw a comment somewhere else that because of warm weather the choke was not used and the chainsaw started, whereas using the correct starting sequence meant the engine was flooding. Although it is only 22 deg C here, which is not hot by some standards, when I tried it on Normal run setting it started ok.

Thanks anyway for me being able to post here.
Best regards
Louis