just MHO... $1600-$2000 won't buy you another 20 yr tractor - mebbe more like 5, depending on where/how used.
Can't speak to Ingersoll parts availability, but if that is not an issue, surely would look at repowering. They were/are quite a machine.

But, do change that tranny hyd fluid.. :)

...sounds like car dilemmas....put the new engine in...then change the fluid that has not been changed in years...then before you know it you need a new tranny!

I'd think / hope / prey a $1400 big box Deer/Ariens/Husk would last more than 5 years if serviced each year and used on less than an acre...of course if you have acres....?????

There were three old lawn tractors sitting in my neighbor's yard. Know something funny, every one of them would run, but not a one of them would mow. Their mower decks wore out, rusted out, long before their motors gave out. I thought that was strange.

You have the opposite problem: the basic part of your Engersoll tractor is fine, but the motor wore out. That's the difference between a quality machine and one that is not, and why you see old John Deere lawn tractors 20, 30, even 40 years, still mowing away.

If I liked it, I would fix it and keep it, if I didn't I would fix it and sell it. I think you could get your repair money back, and then some.

delima #1. 301s to my knowledge are not available anymore short blocks even it you can find them are 1K or more. OK, with that said you never said whats wrong with the engine.

Is it rebuildable? If so rebuilding it would be my first choice. Why? it would be cheaper and easier other than finding used one which is probably about worn-out also which wouldn't buy you much time IMO. If you can rebuild could be done for less than $500 bucks farming out the machine work and doing the labor of dissassemble and assemble providing you have those skills. IF not seek friend with thoses skills.

Now delima #2 No skills, no friends with skills. if engine rebuildable seek out repair shop. Preferable known shop that you had work done or had friends that had work done knowing the quality and workmanship. Probably plan on spending upward $800 bucks.

Delima #3 engine can't be fixed your worse case problem IMO. Now you have to find engine transplant which required major skills to get it to fit and knowing what horz. engine has same specs. plan on spending 1K or more just for the engine and another 300 parts to get it hooked up.

Delima #4 buying another substandard tractor as mensions above your not going to get same standard tractor to mow that many acres without spending 5K or more probably closer to 7K.

I'd repower if the Ingy is in any kind of decent condition. You'd end up with the advantage of a contemporary engine and the design and reliability of a great tractor design which you'd pay dearly for today.

This may be of some interest... http://www.jimsrepairjimstractors.com/case-repower-ingersoll.htm

Some repower kits are easily implemented by basic DIYers, include detailed instructions, and don't require master grade technical skills.

That was a great link lurker. These new tractors pale in comparison to that Case too.

You can get close to the Case for around $10k today and I think Eastman is still making Ingersoll GTs... http://eastmanind.com.mytempweb.com/INGERSOLL/tabid/186/Default.aspx

At link you find a seller that on ebay sell overhaul kit 100.00 machining can be done for another hundred this 200.00 there but you have take it apart clean and reassemble engine.

Here is a link that might be useful: case colt Ingersoll forum

I ended up getting the engine refurbed for a reasonable price and all is well. It was a bit of an adventure because the first mechanic I picked wasn't that great. I found a good website for guidance.
The piston and valves needed to be replaced.

I'll bet you feel better about that rebuild adventure now though.
Cheers! (clink) :^)