Outdoor Power Equipment and Small Engines - Craftsman Lawn Tractor won't turn over

I have a 20 hp twin cylinder tractor that won't turn over. I started mowing and went about 20 ft and it stopped running. I have checked the battery and it is ok. I put a new seloinoid on it but did not help. I checked all the safety switches and they are ok. When I turn the key to start it just makes a click noise and that's all. The engine does not even try to turn. Any suggestions on things I can try or what to do next?
Thanks!

I had a similar issue.

Try taking the spark plug out and turning it over again and post what happens. This will help determine if starter is going or it's compression problem.

Try jumping it at the starter. Maby a bad fuse?

I have checked the fuse and It looks ok. I did remove the two spark plugs
and turned the key, still nothing. Only get a click sound when I turn the
key but nothing happens.

I'm not a pro but I'd make sure you're getting voltage to your starter by doing what msidan suggested.

Hopefully you don't have a seized engine! If your flywheel has a screen that rotates with the flywheel and is therefore accessible on top of the engine (assuming it is a vertical cranked engine, that is) then with the spark plugs removed, can you manually rotate the flywheel using the palms of your hands on the screen? How's the engine oil level and condition?

I am going to check and see if I can turn the shaft by hand this morning.
Thanks for your help and will let you know what I find. I too hope the engine
is not seised.

I removed the spark plugs and put a pipe wrench on the shaft just between
the drive pulley and the mower deck pulley. I was not able to turn the
shaft. I guess that mean the motor is seased??

Any more thoughts?

If the engine is seized, what would a new engine run. The replacement would be a 20hp that would fit my Sears tractor.

Was the engine out of oil? Did it make any odd noises before it died? It does sound like it's siezed, and probably internally. Might be worth checking to be sure the coil isn't against the flywheel, or the magnets under the flywheel haven't come out and jammed it. In any case, if it happened while it was running, it may have ruined it anyway..even if it wasn't internal.

I don't know what engine you have, so it's hard to give an idea of price, but you're probably looking at a list price of around $1000 to $1500 for a new engine at 20 hp. They can be had for less.