Jump to content

Nominations for Tractor of the Month
Garden Tractors and Parts on eBay



Photo
- - - - -

kohler backfire on deceleration


  • Please log in to reply
11 replies to this topic

#1 alec OFFLINE  

alec
  • Senior Member
  • Member No: 61353
  • 382 Thanks
  • 412 posts
  • Location: oregon

Posted June 24, 2015 - 06:19 PM

my 12 hp kohler backfires on deceleration . its not terrible but I know that is a symptom of something

I just fired it up after it sat for a while runs good just backfires slightly . I have marvel in the gas .

to rich to lean ? thanks for any suggestions


  • Lmiller3358 said thank you

#2 olcowhand ONLINE  

olcowhand

    Red Tractor Nut & Diesel Addict

  • Staff Admin
  • Staff
  • -GTt Supporter-
  • Sponsor
  • Contributor
  • Member No: 20
  • 35,653 Thanks
  • 29,840 posts
  • Location: South Central Kentucky

Posted June 24, 2015 - 06:25 PM

Sounds like lean due to an air leak on the intake manifold or maybe a worn throttle shaft, or simply a dirty carb jet.  Marvel may clear it up.


  • MH81, Lmiller3358, superaben and 2 others have said thanks

#3 propane1 ONLINE  

propane1
  • Senior Member
  • Member No: 54307
  • 6,115 Thanks
  • 3,205 posts
  • Location: Charlottetown, Prince Edward Island, Canada

Posted June 24, 2015 - 06:35 PM

Lean mixture, set your high speed jet a little rich. Adjust when on full throttle and warmed up. Turn in, lean, until speed slows a little, then turn out, rich, until speed slows a little, then turn to the middle setting. Then adjust a little rich. Put engine on idle for a few seconds, then put to full throttle very quickly. Engine should speed up with out any delay. If it stumbles abit, then set the mixture a little richer, until it's good. If it does not work, you have other troubles. Check setting of points also. Noel.

Edited by propane1, June 24, 2015 - 06:37 PM.

  • Gtractor, MH81, Lmiller3358 and 2 others have said thanks

#4 DH1 OFFLINE  

DH1

    Electric Tractors

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 62
  • 4,587 Thanks
  • 5,295 posts
  • Location: Markham Ontario Canada

Posted June 24, 2015 - 07:38 PM

I'd say there is a hole in the muffler/exhaust somewhere, that allows air to get sucked in, mixes with the hot rich fuel mixture on deceleration and ignites causing the backfire.

Fix the exhaust leak and the backfire will disappear.


  • olcowhand, MH81, superaben and 1 other said thanks

#5 alec OFFLINE  

alec
  • Senior Member
  • Member No: 61353
  • 382 Thanks
  • 412 posts
  • Location: oregon

Posted June 24, 2015 - 10:28 PM

thanks guys !   I am savin this post . lots of good stuff here .  turns out she just wanted some love , let it run for a bit , oiled the governor linkage and she goes up and down sweet now no backfires the marvel probably did it .. its a mystery oil  :thumbs:


  • olcowhand and MH81 have said thanks

#6 Cvans ONLINE  

Cvans

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Member No: 5412
  • 4,522 Thanks
  • 5,033 posts
  • Location: Eastern SD.

Posted June 24, 2015 - 10:39 PM

I'd say there is a hole in the muffler/exhaust somewhere, that allows air to get sucked in, mixes with the hot rich fuel mixture on deceleration and ignites causing the backfire.

Fix the exhaust leak and the backfire will disappear.

 

I think I will have to agree with the above. If there is no oxygen there can be no fire. If it were lean there would be no fuel to burn. Late ignition timing might also lead to this problem. 

Hope you will report back on what you found so we can learn from your experience. 


  • MH81 and alec have said thanks

#7 alec OFFLINE  

alec
  • Senior Member
  • Member No: 61353
  • 382 Thanks
  • 412 posts
  • Location: oregon

Posted June 24, 2015 - 11:26 PM

I think I will have to agree with the above. If there is no oxygen there can be no fire. If it were lean there would be no fuel to burn. Late ignition timing might also lead to this problem. 

Hope you will report back on what you found so we can learn from your experience. 

look at post  above  yours  :usa: 


  • MH81 and Cvans have said thanks

#8 crittersf1 OFFLINE  

crittersf1

    GT Lunatic

  • Senior Member
  • Member No: 26142
  • 4,169 Thanks
  • 5,761 posts
  • Location: Newport, N.C.

Posted June 25, 2015 - 07:47 AM

Just a little late. :poke:


  • alec said thank you

#9 joel christensen OFFLINE  

joel christensen

    New Member

  • Member
  • Member No: 5954
  • 37 Thanks
  • 21 posts
  • Location: Katy, Tx

Posted June 29, 2015 - 02:30 PM

Question,  Was it a true backfire or a pop.  My John Deere 140 has a pop when you decellerate quickly and it's kinda annoying, but I wouldn't really call it a KaPow backfire.


  • alec said thank you

#10 alec OFFLINE  

alec
  • Senior Member
  • Member No: 61353
  • 382 Thanks
  • 412 posts
  • Location: oregon

Posted June 29, 2015 - 02:41 PM

Question,  Was it a true backfire or a pop.  My John Deere 140 has a pop when you decellerate quickly and it's kinda annoying, but I wouldn't really call it a KaPow backfire.

more pop than kapow but its gotten better



#11 Cvans ONLINE  

Cvans

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Member No: 5412
  • 4,522 Thanks
  • 5,033 posts
  • Location: Eastern SD.

Posted June 30, 2015 - 07:50 PM

You might have some carbon build up in the muffler. This can get hot enough to glow and ignite un-burned fuel when you shut the throttle down. 



#12 TAHOE ONLINE  

TAHOE
  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 24522
  • 6,503 Thanks
  • 4,955 posts
  • Location: "Hamiltucky" Ohio

Posted July 01, 2015 - 07:12 AM

My Sears gets the bad popping/back fire on deceleration if I shut it down quickly, but then my ignition set up is always at advance 25* so it can't catch up if I idle down too quick.


  • alec said thank you




Top