ArboristSite.com Sponsors
 
 


028 idle problem

Discussion in 'Chainsaw' started by MR.STIHL036, Jan 7, 2010.

  1. MR.STIHL036

    MR.STIHL036 ArboristSite Member

    Joined:
    Jan 6, 2010
    Messages:
    68
    Likes Received:
    29
    Location:
    Lincoln Maine
    ever since I bought my 028 the darn thing wont idle right and without the chain brake on the chain still runs at full speed. I have replaced the carb fuel lines impulse tube and the cluch springs fuel filter and it still wont slow down I even have tried the idle screw and it still wont work:confused:
     
  2. jbighump

    jbighump AboristSite Guru

    Joined:
    Nov 10, 2008
    Messages:
    834
    Likes Received:
    75
    Location:
    ky
    sounds like u have a air leak. check the intake boot for cracks if its ok then u have a bad crank seal. you could always pressure and vac test it and find out the problem quickly.:givebeer:
     
  3. redunshee

    redunshee Addicted to ArboristSite

    Joined:
    Oct 16, 2007
    Messages:
    4,834
    Likes Received:
    392
    Location:
    Texas, but spend time in Vermont
    Boy, a differant situation. Have you checked throttle linkeage? Does choke/shutoff switch kick up to run when you squeeze it? Also have you pulled carb and rebuilt it as metering needle may be stuck partially open. I'd start with carb, though often its a non-start or flooding issue for most carbs. I'm sure someone else will offer their opinions. I'd also say you may have an air leak causing it to run lean, but that's only a guess. I've never had your situation so I'm guessing.
     
  4. striperswaper

    striperswaper AboristSite Guru

    Joined:
    Jan 5, 2009
    Messages:
    852
    Likes Received:
    38
    Location:
    ct
    tired clutch?
     
  5. sefh3

    sefh3 Addicted to ArboristSite

    Joined:
    Mar 8, 2007
    Messages:
    6,996
    Likes Received:
    559
    Location:
    Michigan GO BLUE!!!!!!!!
    I'm thinking you are sucking too much air and causing it to rev high. Where are your carb adjustments set at? This will tell us everything you need to know.
     
  6. lone wolf

    lone wolf Tree Freak

    Joined:
    Oct 5, 2009
    Messages:
    20,649
    Likes Received:
    6,224
    Location:
    Prowling The Pine Barrens
    look and see if clutch springs are all good one may be broken.
     
  7. matt9923

    matt9923 Stihl bustin knuckles

    Joined:
    Dec 17, 2008
    Messages:
    4,336
    Likes Received:
    295
    Location:
    CT
    Clutch spring are only a few $. Just put some in my 028

    Clutch Tension spring- 0000 997 5811

    Check crank seals and boot ect for air leak. Does it run erratic?
     
  8. spudulike

    spudulike AboristSite Guru

    Joined:
    Apr 8, 2009
    Messages:
    650
    Likes Received:
    39
    Location:
    Herts UK
    Sounds like classic air leak symptoms to me and a bad one, I would check the crankshaft seals by pressurising the crankcase and using the soapy water, if it isn't this then the jug base gasket and carb gaskets. There is nice video of a pressure check on this site - think it may be one of Brads and is worth a look - would think your seal/seals are pretty far gone IMHO.

    My jonsered 630 had a real bad crank seal, as soon as the saw started, it would run at half WOT, the only way I could get the idle down was to run the idle at super rich 2.5 - 3.5 turns out but it would run smokey and foul up. The idle adjustment could be left out and it would still fast idle.

    It is worth looking at the carb and making sure the butterfly valve closes up fully but my smart money is on an airleak.

    Good luck - let us know what you find

    Spud
     
  9. MR.STIHL036

    MR.STIHL036 ArboristSite Member

    Joined:
    Jan 6, 2010
    Messages:
    68
    Likes Received:
    29
    Location:
    Lincoln Maine
    028 problem

    Well it could be any of the problems that you all have listed I hope its not the cluch springs because I just had my local Stihl service center profsionaly replaced along with the carb wich is a new OEM part from walbro. Being a 25 year old saw the cluch is probly tired. This saw has a like new 16''stihl bar and chain that I put on back in may. Anyways the carb may have been rebuilt wrong.
     
  10. matt9923

    matt9923 Stihl bustin knuckles

    Joined:
    Dec 17, 2008
    Messages:
    4,336
    Likes Received:
    295
    Location:
    CT
    New clutch? there cheap and easy to fix, not sure what the big deal would be.
     
  11. spudulike

    spudulike AboristSite Guru

    Joined:
    Apr 8, 2009
    Messages:
    650
    Likes Received:
    39
    Location:
    Herts UK
    Weak clutch springs will cause the chain to spin at slow speed or to pulse forward as the clutch catches the clutch drum - it will now make the chain spin at a very fast speed or effect the idle speed.

    I would rather have shot springs than bad crank seals but my diagnosis of a fast idling saw where you cant bring down the idele speed is an air leak - probably crank seals - think of a saw just about to die as it runs out of fuel - the idle begins to race as the mixture goes weak- just like the symtoms of this saw problem and it is caused by a weak mixture.

    Get the thing pressure tested - a length of hosepipe, some plummers maite to block the inlet and outlet and some soapy water is all you need for a very basic test.

    best of luck

    Spud
     
  12. sefh3

    sefh3 Addicted to ArboristSite

    Joined:
    Mar 8, 2007
    Messages:
    6,996
    Likes Received:
    559
    Location:
    Michigan GO BLUE!!!!!!!!
    Before throwing money at the saw, do a pressure/vac test. That will tell you everything. With the knowledge I have, the springs would cause the chain to skip or be inconsistant.
     
  13. Paul001

    Paul001 Addicted to ArboristSite

    Joined:
    Dec 10, 2008
    Messages:
    1,198
    Likes Received:
    132
    Location:
    NJ
    Would double check that reciept, as the OEM carb hasn't been available for sometime...

    Most likely they rebuilt the carb.

    Do a pressure/vac test (see my sig.) and go from there.
     
    sefh3 likes this.
  14. Mastermind

    Mastermind Work Saw Specialist

    Joined:
    Nov 21, 2009
    Messages:
    32,555
    Likes Received:
    19,645
    Location:
    Tennessee
    I had the same problem with an 028. I bought a used case from ebay, put it all together it ran fast at idle, it would only idle down with the low speed mixture screw out 3 turns or so, and then it was erratic. A pressure / vac test is easy to do and will tell volumes, do a search. In an 028 the seals are easy to change without special tools, a flywheel puller is a must though. Seals fixed mine. It idles great and the bog is gone when revving up.
     

Share This Page