Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Sign in to follow this  
richp

A/C 912H Backfire

Recommended Posts

richp
Sorry, inexperience spoken here: What makes my 912H with Kohler 12hp backfire? Didn't do it during first two mowings, now filled it up with new regular gas and it backfires when I turn engine off. Know this is a basic, but I don't know.

Share this post


Link to post
Share on other sites
richp
I've had tractors in the past that if you didn't idle them down before shutdown, they would build up so much heat in the combustion chamber that they would ignight excess fuel built up after ignition stops.Don't know if thats your prob. but it is good to idle down before shutting off. Just A thought.
Rich

Share this post


Link to post
Share on other sites
tej
Brett, I second Rich's recommendation. I don't know Kohlers but some engines don't like certain brands of gas, I normally use Exxon. Also carbon build up in the combustion chamber can cause backfire as it stays hot enough to ingnite the gas. If it only happened after putting in new gas I'd try another brand. Tim

Share this post


Link to post
Share on other sites
Kent
Thanks guys, idling down for a minute or two seems to stop the backfire. Does backfiring have any adverse affect on an engine or is it just a loud nuisance?

Share this post


Link to post
Share on other sites
paull
Hi Brett, will you stop cutting your self short on experience as we all have to learn somehow and if you didn't ask questions none of us would have anything to do. I totally agree with Rich & my goodest friend Tim about the back fire and if you don't idle the engine down when hot raw gas empty's into the muffler and the heat from it inites the raw gas and thus a back fire. Or it can do the same in the cylinder. Alot of twin cylinders are prone to this also. Just keep asking your questions please.->jackl-happyjack<-

Share this post


Link to post
Share on other sites
Fred
Hi Brett,
Yup, we're back from our trip, so I can bug you again!
ALL "air-cooled" (in reality air AND oil cooled) engines must be idled for a few minutes before shutdown after being worked. This will greatly reduce top-end temperatures and contributes more than a little to engine life. The backfire will usually do no harm, but can't do any good.
If this gets to be an ongoing problem, you may need to de-carbon the top of the engine. Don't worry, we can walk you through that.
Fred

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

  • Who's Online (See full list)

    • timmangan
    • Legacy Dave
    • ShaunE
  • Today's Birthdays

    1. 720nut
      720nut
      (66 years old)
    2. Joe Scann
      Joe Scann
      (79 years old)
  • Recent Status Updates

    • Paul M.Murphy

      Paul M.Murphy

      Hello glad I got on this site. I hope to upload a couple of photos of my Simplicity Broadmoor 
      Model 707 Tractor. I have replaced all the belts on it and installed a new ignition switch.
      Have a mower deck which was in poor shape , repaced a couple of bushings and welded the
      deck where there was some holes. The tractor and mower deck came from a friend and the 
      mower deck metal was getting pretty thin. Some new metal was put in it and we also undercoated the underside of the deck. This was done by my friend Greg Toulman.
      I have not put the mower deck on the tractor yet, waiting for Greg to come home and give me a hand. Can you please tell me if there is a manual for the mower deck and where I could get one.
      I would also like to get some moon wheel discs as well.
      I will try and down load some photos of the tractor when my wife shows me how to. 
      I really love driving this tractor and also how well it is made compare today's tractors, especially the flexible rear end and the rollers.
      Tell the next time 
      Paul
       
      · 9 replies
    • jbrooks

      jbrooks  »  Talntedmrgreen

      Josh
       
      folowing  this from a link at the downloads.  I just rescued an AC 920 with the lambodini diesel. I can' t download  yet .  Where did you find the PDF copy you posted. . I would like to figure out how to adjust the injection pump. 
      I assume it's a bosche, correct
      · 0 replies
  • Adverts

×