Echo-370 Chain Saw Full Throttle Problem

Discussion in 'Mechanic and Repair' started by jud149, Feb 2, 2012.

  1. jud149

    jud149 LawnSite Member
    Posts: 102

    This saw has only about a couple of hours on it but is several years old. I used it about a year ago and it ran fine. I ran the gas out of it before storing it. Today it will not run a full speed, only 3/4 and then will cut out periodically. However, it does idle fine. Now I just noticed that if I run it at about 1/4 choke, it will run at full speed.

    The filters are obviously clean and I put a new plug in it as the old one was black, and removed the spark arrester which was clean. I tried to adjust the carb but to no avail. You can only turn the screws a half turn or so. Any ideas or is this just another carb I will have to rebuild because of ethenol? I have recently converted to non-ethenol fuel.
     
  2. dutch1

    dutch1 LawnSite Silver Member
    from Jayhawk
    Posts: 2,231

    Remove the limiter cap and open the high speed needle a bit at a time--see if that might help.
     
  3. jud149

    jud149 LawnSite Member
    Posts: 102

    Thanks! Would you happen to know how to get the limiters off? I have the top and side off the saw but still can't see how to get to them. They are flush with a metal base with limited access.
     
  4. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,246

    Walbro makes a tool that threads into the caps and threads them off.
    You may be able to thread a small screw into the caps and pull them out.
    Posted via Mobile Device
     
  5. dutch1

    dutch1 LawnSite Silver Member
    from Jayhawk
    Posts: 2,231

    The proper way to remove the external limiters is with the Walbro tool as Slapper suggested. I've also heard of guys running a sheetmetal screw into them to push them off but have never tried that method. I've always use a duckbill plier to grasp the outer part of the limiter and pull straight out--along the same axis of the adjustment screws. Twisting or bending may result of bent needles or possibly breaking the needle off in the carb. I've even cut them off with a pair of miniature side cutters.
     
  6. jud149

    jud149 LawnSite Member
    Posts: 102

    There's no way to remove the limiters with pliers as they are flush with a metal extension on the carb. I probably can get them off with a screw as suggested but once the carb is adjusted, I believe they must be replaced since the adj. screws have no spring to hold them in place. What a joke. I knew there was a reason I keep my old Echo SRM 1501 weed whacker despite having some minor problems with it. Thanks again for your help, guys.
     
  7. jud149

    jud149 LawnSite Member
    Posts: 102

    I should add that the old ones will probably be destroyed and I understand new ones are not easy to come by. Does anyone know where to buy the tool?
     
  8. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,246

    Jud....the caps aren't gonna make it run any better.
    You can pry out the aluminum face cover that is shielding the screws, with a flat screwdriver.
    Once you get the caps off the screws, they'll just look like screws.
    A whole lot more user friendly.
    Posted via Mobile Device
     
  9. dutch1

    dutch1 LawnSite Silver Member
    from Jayhawk
    Posts: 2,231

  10. piston slapper

    piston slapper LawnSite Platinum Member
    Posts: 4,246

    You're probably right. Dutch.
    My research dept has been out to lunch for some time.
    Posted via Mobile Device
     

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