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unknown motor problem


ac712

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okay not sure whats going on. i have a k301 in my tractor. it seems that the motor is putting ALOT of heat. and after about 30 min of mowing it started to spit, sputter and was backfiring. when i got it into the garage and shut down it sounded like the carb was gurgling. would this be a valve sticking, carb issue, or fuel? any help would be great.
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Check for trash under the blower housing. Gurgling gasoline is a sign of extreme radiant heat and the lack of of air flow. My guess is mouse nest.
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quote:
Originally posted by BLT
Check for trash under the blower housing. Gurgling gasoline is a sign of extreme radiant heat and the lack of of air flow. My guess is mouse nest.
agree, check that first. timeing may also be too far advanced. does the engine make a rattle sounds ?.
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Ok thank you BLT i will check that. you are talking about the cover on the flywheel side of the motor right?
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Perry, doesnt seem to be making any noise. I know that something is wrong, i've never seen a motor get that hot before. it was so hot i could barely take off the air cleaner cover.
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Mice or the dreaded southern dirt dauber wasp. Has it been raining a lot where you are? Gives em a lot of mud to play with
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nothing down around the fins on the flywheel, actually looks pretty clean. there is a little bit of stuff on the screen where the drive shaft is hooked on, i'm going to clear that out and try adjusting the carb. the kohler service manual said overheating could be caused by carb out of adjustment.
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Did you actually pull off blower housing to chck horizontal fins for bockage? That is where I believe your problem lies.
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You can unscrew the tins on the sides of the engine for a better look at the engine's cooling fins. There could be accumulated layer of old crawp, dirt, dust, decomposed grass, mud, residues from whatever, oil, gas spillage, etc. all built up between the cooling fins, inhibiting the normal cooling system. On mine I had the blower cover loose; but never pulled it off cos I didn't want to mess with drive shaft etc etc. But I had a flashlight, trouble light in there and got a good luck at it - altho it's kinda awkward. Carb set lean can cause overheats also; but if you are boiling and baking in a pizza oven, the mouse condo or blocked, gummed up, jammed up, air pathways is a better bet. Do not run engine without the tins in place! A basic test is to idle the engine, and "feel the breeze" free flowing through the cooling tins, near top front of engine, blowing on the muffler, at the grille, etc. - it's a strong flow at even idle speed ! But that can still happen if there's residues on the cool fins, acting as insulation, reducing heat transfer rate. If you just pull the top tins and run a popsicle stick or wood chip or screwdriver through between the cool fins, that might tell you something - good or bad. ? Also quit running nitro methane; unless actually drag racing.... :D 8D 8) I really don't know the best, recommended way to CLEAN the beast. I used a pressure washer on a hot sunny day, and then I let it sit for hours before I tried to start it, to avoid electrical chaos. Maybe degreaser and a big rinse, would be better; but I didn't have that - really not sure what's best. ???? Maybe someone else does.
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I have had plenty of experience with K series Kohlers from my Cub Cadet days, and the above suggestions are good. Letting a K series Kohler run too hot for too long is a bad thing. If you tried the above suggestions and you are still stuck, here are a couple more, particularly if the engine has high/unknown hours or previous work on it. Retarded timing generally won't make it knock, but since the fuel is still burning when the exhaust valve opens, your exhaust pipe can get red hot. Since the engine is running inefficiently, it will use even more fuel and adding more heat, aggravating things even more. Without a timing light or access to the timing mark on wide frame Cubs, I usually tuned it by ear, working back and forth between the timing and the mixture. If you find you have to adjust the timing frequently, or if it seems to change as the engine gets hotter, there is a good chance the camshaft has a groove worn on the points lobe, but before I went to all that trouble and expense I would check to make sure the points themselves are not worn or have a cracked insulator. Here is a picture of the cam out of an old 301 that had the same issue.


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Hey guys thank you for all the tips. I ended up pulling the motor out, taking off the blower shroud and cleaned all the fins real good. Used a small screwdriver to get all the crud loosened up then took my shop vac and an air hose and got it cleaned up pretty good. adjusted the carb back to "factory" settings and finished mowing...took a little over 20 min. It ran alot smoother than it ever has so i'm guessing the carb was set wrong and the motor seemed to still be pretty cool. Guess we'll see later this week when I have to mow again.
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Welcome to the site bnolte. You are spot on with timing and I mentioned it in here and was questioned about it and frankly I do not think not taken seriosly on it. I have found .020" point gap is on the light side and .o22" will net better performance and less fuel used. KT Twins benefit more from this than the singles.
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