Heymow - Lawnmower Racing Forum
Engine Help => Kohler Engines => Topic started by: hatt64 on July 26, 2012, 10:50:01 pm
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buddy has a craftsman mower with a 25 hp on it. he was cutting grass with it and after about thirty minutes of running a flame was was blowingout of muffler and stopped to see what was going on and it died and would not start 2nd time this has happened any ideas thanks Bo
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Too much fuel?
Exhaust valve hanging up?
Look at the plug(s), what do they tell you?
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Could also be a timing issue. Id check the flywheel key to see if it has sheared.
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ok done a little more investigating only the left pipe coming fron head seems to be burnt.the right is pretty much same color alway down.pulled the valve cover and noticed that the valves dont seem to be closing completely. i loosend the intake and axhaust rockers (and tuned engine so that in and ex was supposed to be closed) but still had pressure on valves, not much but enough to notice.anybody run across this before could it a lifter going bad.checked plug and you could see sighs of excessive heat but still aint checked the timing any help would be appreciated
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Yep I've had the lifters pump up enough to bend the push rods. I replaced the lifters and push rods problem has not returned. I brought it up on here I will use the search and see if I can find it.http://www.heymow.com/index.php?topic=17235.0 (http://www.heymow.com/index.php?topic=17235.0) That pretty much covers it
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ok i have checked the timing its ok, pulled both plugs and they were covered in smut, after looking a little closer i noticed the left header was burnt, right side was basically the same color all way down, checked pushrods and all 4 were still straight. now i found that exhaust was blowing back out of the muffler on front of engine and also found smut on the bottom of the carb,and yess the muffler is worn out. both sleeves inside the muffler i guess that is what they are called any how the pieces that the header pipes go into inside the muffler are loose and rattle.could this be part of the problem im having exhaust blowing back up on the carb maybe increasing the pressure inside the carb and pushing excess gas and causing it ti run lean?just dont want to spend a $100 for a muffler if it aint the problem. oh yeah,done a compression test and neither cylinder leaked down. right now im lost as ball in high weeds thanks guys to those of you who responded thanks Bo :bash: