Seized Kohler K321 - Cub Cadet 1450
 

Yesterday I was using my Cub Cadet 1450 to mow the backyard. The tractor mowed and ran fine, up until when I put it back in the barn. The tractor had been sitting in front of the door from about 12:30pm-9:30pm. Since it was dark out I had not noticed that the oil drain plug had fallen out, consequently, allowing all of the oil in the crankcase to drain out.
I did not bother to check the oil when I put it away, as I had checked before I started the first time, as I always do. Anyway, I started the tractor, it didn't start very well and made sort of a clunk-clunk-clunk sound. I knew the engine sounded not quite right, but since I was only putting 20' feet into the barn, I figured I would have a look at it inside, as it was dark out and I couldn't see anything, anyway. It started blowing blue smoke from the front of the machine. At first I thought it was probably the deck belt or something like that. Upon putting the tractor back into the barn, I pulled the dipstick and realized where the real problem was.
Today, I refilled the crankcase with fresh oil, that was going to drain out, that way I would be able to tell if there were metal shards in the engine.
Not being able to turn the engine over, I suspected a dead battery, I put the volt meter on it, this was not the case. I then tried to turn the the camshaft with my hands, no dice.

Not wanting to ruinthe engine further I haven't tried anything else, besides some penetrating lubricant sprayed into the spark plug hole, to try to lossen the piston.

I'm not against fixing it myself, but I'm not sure what the next step sould be.
Is there something else I should try to free the piston, or do I need to start disassembling the engine, and opening it up?

Pull the engine...don't run it anymore. Anymore running could destroy what left of anything worth saving for a rebuild.

I would think the engine is definitely worth saving, as it was literally run less then 1 minute. It was sitting right outside the barn door and all I did was drive it inside - just barley inside, and then I shut the engine off as soon as it was in the doorway.
What kind of damage could occur in 1 minute that would totally ruin the engine for a rebuild?

Thanks for the help.

Well that is about a bummer of a story. Sorry about the mess.
I am curious as to how the drain plug fell out though. Had you just
changed it and didn't get it back in? Or did something else go wrong to
create the problem?

Ken

I had just recently changed the oil, but I had also mowed with it 2 other times before. I know I had the plug bolt all the way tight, because when I had first started refiling the crankcase I didn't have it all the way tight and the oil was leaking out around it.
The only thing I noticed when I looked at it today was there was a old cracked, uneven gasket around the top of the bolt. My dad wondered if the uneven gasket could have caused it to tighten unevenly, hence, causing it to slowly back out with the engine vibrations.

On a side note, my uncle said that because it was only run for about 1 minute, that it could just be the crankshaft bearings are seized. If it is that, it would be a relatively cheap fix, as they only cost about $70.

I won't know if it is that until later this week, because I have another mower I'm the process of finishing fixing for someone else.

If I understand this story correctly, you have quite a bit of run time on it since the oil change and then the oil drain plug just decided to fall out after you parked it at the barn door?

I surmise that because you still have the drain plug to add new oil and/or notice that the bolt gasket is cracked/uneven, so you must have found it where the tractor was parked.

On the other hand if it fell out while you were mowing, the tractor was likely run without oil for a lot more than the 20 feet/1 minute you are suggesting.

I wonder :bigthink:

1st step: Pull the engine and drop the pan for evaluation.
If you are lucky, you will only need a new rod and have the crank polished.
If you really want to save this Cub.....
"Do it right6 and do it once"

I know that it wasn't leaking before, be able I checked it before I started mowing and it was full. Plus, there was no oil on the shield when I pulled the grass off.
I know the majority of the oil leaked out where it was parked, because the next day I found a big oil mess I n the gravel driveway.

There isn't a lot if run time on it, the backyard only takes me about 20-25 minutes to mow.