Cold Kohler Command 20.5 wont start..

My lawnmower was running last night then tonight I went to start it and nothing. It is -10 outside and I hear the starter hitting the fly wheel and nothing. Tried to grab a wrench and turn the top nut under the plastic grill a turn and nothing. Any ideas? I hope I did not blow the engine? The tractor was out and running fine yesterday and I shut it off when I pulled it in. Seemed to shut off fine. It is a Kohler Command 20.5hp. Another side note if this engine blows which I do not think it is because I was running it yesterday what kind of upgraded engines can I find for cheap? A 19.5 briggs would be nice.. Give me your thoughts. Thanks

I was gonna say your battery doesnt have enough CCAs but I dunno. Could be your oil froze but I doubt it, unless there was water in it.

If it was blown it would turn.

I hooked my battery jumper up to it.. Do you think it might have to much compression? One of the valves stuck? I am running a 30 weight oil. I doubt the oil froze... LOL.. I hope not anyway..

Sounds siezed but....

How hard did you try to turn the engine over with the wrench?
Does it still have oil in it.
Were you running modified exhaust or carb?
Did you tilt it at an odd angle?
When you put the wrench on the crankshaft was there ANY movement at all. ( a crank siezed engine will have NO slop on the flywheel, If its ring or piston siezed it will have a slight bit of slop. VERY SLIGHT, You have to look/feel carefully. make sure you account for the slop in the wrench itself


If its ring or piston siezed and it has a large amount of play at the flywheel, it needs a new connecting rod for starters, probably a new crank and piston and rings too.

It's not un common for an engine to seem to be running just fine, only to lock up after it cools down. Galled rings can di it, or a spun bearing/bushing

Engine still has oil. I took a wrench to it and got it to move back and fourth about 1/4 of the way around if that. Funny thing is that it ran fine last night then I shut it off and a day later it would not turn over. I took the electronic PTO off and starter off. I took the plugs out also. Starter works fine and I could not turn it over far enough to check the compression. I do not think it was a connecting rod because it did not have enough play. I think something is lodged in the flywheel somewhere or something. I will take the plastics off tomorrow and double check. The carb was stock and the exhaust was just a cheap tractor supply glasspack. Sometimes it is important not to get upset but to walk away and laugh about it. I now have a DONER tractor to set up for a 2 cyl diesel or a reliable engine. Newer Kohlers are worthless. I can probably sell the engine even though it needs work for a few bucks. Any recommendations on a good diesel engine to take the place of the kohler? I will probably weld a steel mounting frame for a new engine..

When you turn the flywheel and it gets to the point where it stops, does it sound like its hitting metal or does it just stop with no sound or feel feedback?

I would take the rocket cover off (if OHV) and check in there, also try taking the head off and see it there is something in the cylinder, Water may have got in and rusted the cylinder wall stopping the piston.
If nothing has broken and the engines not seized, I can't understand why the engine would lock like it has.

all my briggs try and pull that crap when its 20 degrees or colder out, I leave them on a trickle charger in cold weatherto help a lil bit with the battery. to get them to crank i usually spin the motor over by hand a few times to get everything lossened up and then i jump it with the jumper pack.....usually starts right up...HTH

It sounds like it is hitting metal. I also cant get it to turn over because this fuse keeps blowing next to the battery. I probably melted a wire?

well that's not a good sign, like i said, you may want to take to rocket cover and head off and inspect it all. If all is good then you may need to open the crack case. Try warning the engine up the a non flame heater for a couple of hours and turning the engine by hand in both diractions to find out weather the metal has simple contracted too much making it stiff.

The fuse will blow if the starter is pulling to much current. It could be that the starter in just working harder then you have allowed it (by the fuse rating) or yes you could have a short. Does the fuse blow as soon at you turn the key or push the button or is there any delay?

There is a short delay of a few seconds yes.

I'd pull the plug and put a wooden dowel down the hole then turn the crank and see if the piston moves.

Just did they do move.. Made 2 videos will upload them in a few.

CraftsMAN wrote:

There is a short delay of a few seconds yes.

That tells me that the starter is pulling to much current for that fuse, not a short. If you had a short, the fuse would normally blow as soon as you turn the key or push the start button.

You can take the fuse out while your fixing it, just make sure you dont hold down the button or key for very long. This will allow a few more amps to the starter and stops you blowing $20 on fuses. You should replace it when you fix it for safety.

If i read correctly, the piston is moving up and down normally right? If you can id warm the block up with a heater for a couple of hours and see if it helps free the engine up.

New videos are under my Mowerracertt account. They are uploading now..
https://youtu.be/4NHDcqOIAJc
https://youtu.be/sYX8MYMXRQQ

I watched the first one and it turns and seems to have good compression. It has to be the starter. or possibly the solenoid.

Did you try to bypass the solenoid with jumper cables?

i saw a viedo while back, guy had same problem and it was a bad diode in one of his wires.

where in the circuit is the fuse? what does it protect?

and don't try to crank it till you know what the noise is.

Still waiting for second vid to load

i think his was on the hot wire coming off engine.

watch his video on you tube, its 805roadking, LAWN TRACTOR ELECTRICAL PROBLEM REPAIRED

It sounds like something is dragging under the flywheel. The metal shavings confirm it.

Are both coils properly gapped? I couldn't tell from the video.

If the coils aren't touching the flywheel, then you'ld best pop the flywheel off for a better look.

The fuse should only protect the battery from everything except the main line to the starter.

yeah there is something really wrong under that flywheel. pull it off and see.

I bypassed the solenoid and did a bench test on the starter. It coiled over. I remember trying to remove a flywheel a while back and it was a pain in the butt. Anyone have an easier way?

depends on the exact flywheel.

Some flywheels have threaded holes in them that you can run a bolt into to push the flywheel off.

maybe a crank bearing under the flywheel when out or sumtin