Jones Red Chain Saw Idle Adjustment

Discussion in 'Shop Talk' started by Gunner, Oct 30, 2004.

  1. Gunner

    Gunner Member

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    Can anyone out there explain how to adjust the idle on these saws. The chain runs when the saw is at idle and I need to slow 'er down. Thanks!
     
  2. bumpus

    bumpus Well-Known Member

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    .
    Take the air filter of and work the throttle
    and you will see the adjusting screw.

    Turn it out counter clock wise.

    .
     

  3. Ross

    Ross Moderator Staff Member Supporter

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    Maybe your air filter is a bit plugged. Clean it or replace it first. If it's starved for air it will draw gas
     
  4. Cabin Fever

    Cabin Fever Life NRA Member since 1976 Supporter

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    I have two Jonsered chainsaws and a Jonsered brushcutter. There are three adjustment screws on the carburetors of these saws. Access to the adjustment screws are through three holes in the body of the saw. The holes are labelled: L, H and T.

    L = Low speed jet
    H = High speed jet
    T = Idle adjustment screw

    The L and H jets are used to adust the supply of fuel to match the rate that air is admitted, which is controlled with the throttle. If they are screwed clockwise the air/fuel mixture becomes leaner and if the are turned counter-clockwise the mixture become richer. A lean mixture gives a higher engine speed and a rich mixture a lower engine speed.

    The T-screw regulates the throttle setting at idle speed. If the T-screw is turned clockwise this gives a higher idle speed; turning counter-clockwise gives a lower idle speed.

    When adjusting, first adjust the L-jet, then the T-idle screw and then the H-jet.