1. Can’t make it to the GIE+EXPO 2017?
    LawnSite brings the trade show floor to your fingertips with our new GIE+EXPO 2017 Sneak Peek video series debuting now in the Lawn Mowing forum.

    Dismiss Notice

Stihl FS85 AV will not start

Discussion in 'Mechanic and Repair' started by dgwestfall, Sep 12, 2009.

  1. dgwestfall

    dgwestfall LawnSite Member
    Messages: 1

    I am new here, and glad I found this forum.

    I have a Stihl FS85 AV (I can't find anything on the Internet with the AV after FS85...any way to tell how old this thing is?) I have a few questions, as it will not start.

    When I spray starting fluid back in the intake (took the air filter off) it will start for about 1 second and then sputter and quit. So I assume I am getting spark. Could anyone tell me where I need to start? I plan on taking the carb off and cleaning everything really well. I will also check the fuel pick up in the tank, as I read these can get clogged up as well.

    Should I just rebuild the carb while I have it off and can see what model the carb is?

    This trimmer looks really old...any way to tell how old it is?

    Final question...this thing never seemed to have that much power. I could use it fine as a string trimmer, but when trying to mow taller grass with the nylon blades, it boggs down quickly. Are these trimmers pretty powerful?

    Thanks for your patience! I have fairly good knowledge when it comes to cars, but not much when it comes to lawn equipment. I know the basics though, enough to get myself in trouble. Thank you!:)
  2. hate2work

    hate2work LawnSite Member
    Messages: 90

    I suggest you simply replace the carburetor. I have not had very good results rebuilding these carbs. Cost should be around $65 to $80, depending on the source you use. Change the FF as well.

    IIRC, these were rated at 1.1 HP. Not a real powerhouse, but good for trimming.

    Post the serial number, I'll look in the database to see if the selling dealer sent in the registration, that would tell us the purchase date.

Share This Page