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Does Heat Affect Mtronics in a Stihl?

Discussion in 'Chainsaws and Power Equipment' started by buZZsaw BRAD, May 12, 2023.

  1. buZZsaw BRAD

    buZZsaw BRAD

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    Fired up my 261c yesterday and it ran very erratic. It had been in back of the PU in full sun and high near 80.
    "Cold" started ok but sputtered when i hit the throttle and stalled. Wouldnt get full power right away. Multiple pulls to hot start. Havent used it in a few weeks. Had me puzzled and aggravated! :headbang:
     
  2. stuckinthemuck

    stuckinthemuck

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    Consider running it through the tuning regimen that is outlined in the owners manual. Also, I have found that when restarting a hot saw, sometimes one needs to fully squeeze the trigger while pulling the starter to get it going. Saw it on a video and it worked for me 661 and my neighbors 261. Not sure why.
     
  3. RCBS

    RCBS

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    Heat can affect gasoline quality. Try some fresh stuff.
     
  4. brenndatomu

    brenndatomu

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    Fully opening the throttle while cranking on most fuel injected engines shuts the injectors off...often allowing a "flooded" engine to clear enough to fire...works on a carburetor engine too. Dunno what it does on the Mtronic...
     
  5. mike bayerl

    mike bayerl

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    Try canned gas, like TruFuel. Also, let it cool down at idle for 30-60 before shutting off in hot weather. If having trouble with hot start, set to "Run" not start, hold throttle trigger and pull multiple times. This often works.
     
  6. Canadian border VT

    Canadian border VT

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    What am I missing? Isn’t the C model a carb not a MTronic?
     
  7. The Wood Wolverine

    The Wood Wolverine

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    If a tank vent wasn't properly working, could the pressure build affect anything huskihl ?
     
  8. Chud

    Chud

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    I left a saw in a hot truck once and it ruined the tank vent. How’s the air filter looking? Bummer to have your #1 acting up. Maybe it’s just having abandonment issues.
     
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  9. stuckinthemuck

    stuckinthemuck

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    M-tronic is an electronically tuned carburetor. “C” stands for “comfort”. “M” stands for M-tronic.
     
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  10. buZZsaw BRAD

    buZZsaw BRAD

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    Any "Pro" model Stihl with the "C" designation is mtronic....661c, 462c, 261c etc. The ones without the "C" are the manually adjustable carbs.
     
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  11. buZZsaw BRAD

    buZZsaw BRAD

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    Mix is a month old.
     
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  12. buZZsaw BRAD

    buZZsaw BRAD

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    Didnt think of that. Ill give it a check. Thanks.
     
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  13. buZZsaw BRAD

    buZZsaw BRAD

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    The saw automatically resets to "run" when shut off. Either "off" "run" or "choke"
     
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  14. Canadian border VT

    Canadian border VT

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    Thanks for educating me! Brad:handshake:
     
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  15. buZZsaw BRAD

    buZZsaw BRAD

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    Glad to help Lyle. Passing on the knowledge. One reason i love this forum so much.
     
  16. huskihl

    huskihl

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    Winter fuel on a hot day. Dump it out and get fresh fuel. Videos all over YouTube this year of winter fuel boiling on hot days causing all sorts of mtron and autotune issues
     
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  17. huskihl

    huskihl

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    The tank vents don’t vent out now like they used to. It’s not a terrible thing though. The pressure in the tank helps prevent the fuel from boiling on hot days. Similar to antifreeze in your radiator
     
  18. huskihl

    huskihl

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    It’s actually a C-M. But the recoil badge only has the C. Makes it confusing
     
  19. Canadian border VT

    Canadian border VT

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    Ahh More info from smart people :yes:
    Thought there was M for mtronic
     
    Last edited: May 12, 2023
  20. stuckinthemuck

    stuckinthemuck

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    While that is true of the pro saws that are currently offered because all “c” designated pro saws are also m designated saws, it is not true that ALL saws with the c designation are mtronic. Previously, there were pro saws that were “c” designated such as the MS362C-Q which was a comfort-quick stop saw but not mtronic and thus manually adjustable..
     

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