On 8-1-2011, I finally got my engine back from the machinists, it has been there since 4-7-2011, wow...almost 4 months! I had told him I wasn't in a big hurry, and actually I am still not ready for it, so the 4 month wait was a non-issue. I was hoping to have most of the tractor painted and ready to put everything back together, but work and the heat wave have keep me away from the shop, so not much has been done.

This motor was in horrible shape, the cylinder was previously bored to .030 over, and was worn beyond that. The original crank was worn to .019 under, if you remember, I parted a 125, it sacrificed it's crank to the 149 rebuild (the motor was junk, it was cracked through the side of the cylinder near the exhaust port, at least the crank was in good shape). I wound up spending a total of $248.64 at the machine shop to get it back in shape. The break down of work done and costs follow:

Hot tank engine..........................................15 .00
Install cylinder sleeve/ bore block to stock.....130.00
Valve job............................................... ....20.00
surface head.............................................. 10.00
grind crank (.010 under)...............................35.00
remove exhaust pipe....................................15.00
kohler exhaust valve....................................22.00
tax (on parts, the valve)..............................1.64
total............................................. ..........$248.64

I see lots of people ask on here what machine shop work costs, I realize they vary greatly based on location, but thought I would include what it cost me to give those wondering a loose baseline to go from. If I remember correctly, I think had I only needed to have the cylinder bored, it was about $40.00, sleeving the block was the only route I had available to salvage the engine(unless I could have sutmbled upon another K321, believe me I looked, no luck finding them around here).

Hopefully in the next few days I can get started on reassembling the motor, when I do, I will post the pics. Just thought I ought to update my thread, got to keep everyone up to speed!

Thanks for the update. Those numbers, though subject to regional variation, are pretty helpful to those of us who have never had any work like this done.

Just read this entire thread, from beginning to end. Great documentation, this is the kind of thing I would love to be able to do someday to my 129. Great insights, and quality work for sure. I'm liking all the little modifications you're doing along the way.

Congrats on getting the engine back!!

Looking forward to the rest of the story....

Justin

Thanks for the compliments! I have tried to keep the tractor more or less stock, just trying to improve on an already excellent design. Of course the most noticeable change is the change in color, but there are 2 mods that I am glad I tried. The first being the steering upgrades, when I got thus tractor, I would guess it had a third of rotation of the steering wheel worth of slack in the steering. Now it has absolutely no slack, it had slack in the steering box, tierod ends, and front axle pivot point, the front axle near the ends would move back and forth about an inch. I learned of the steering box upgrade (bearing to replace inner jamb nut) by reading threads here, and I decided on my own to replace the axle pivot pin with a bolt and jamb nut, these two additions plus replacing all the tierod ends made it great. The way the tractor sits right now (nose light without an engine) you can turn it lock to lock with one finger! As the engine and rest if the front end parts are assembled, I am sure it will increase the steering effort, but when I got it it took two hands to crank the steering.
The other upgrade I made that I think improved the tractor was the rear wheel studs. I cannot believe they came factory with wheel bolts, the studs make rear wheel changes a breeze. I don't have loaded rears or wheel weights yet, but I can't image trying to mount them on the tractor without the studs, what a PITA.

Hopefully I can get back to work on it and get some more pics on here, I am really looking forward to putting it back to work.

That's not bad for a engine rebuild. I'm going to have my 128s motor rebuilt soon by a guy that builds pulling motors. I'm having bore to a 14hp than a cheater cam that adds 3hp so it will be a 16hp:biggrin2:! The place is called Lakota racing if anyone has heared of them.

If I were you I would not bore a K301 to a K321 bore. I have heard of cylinder failures because what remains of the cylinder wall is too thin when this is done. If you want a K321 bore, get a K321 block.

I would have to agree with Matt on this one. After having both a 301 and 321 apart, the issue with boring one that much would be at the lower part of the cylinder. The cylinder wall is very thin at the bottom of the stroke, I had the same idea on the 321, boring to the larger 341, but this issue was pointed out to me by the machinist (not to mention in my case, the placement of the head bolts, the 341 uses a different head, with the head bolts move away from the cylinders bore). The second point is a non issue in your case, the 301 and 321 use the same head. I am sure you could do what you are wanting to do by adding a sleeve to the engine, without the sleeve I think you are setting yourself up for a broken block in the future.

I was thinking about that.What i'll do is bore it 10 over than put the cam in it. Thanks for letting me know about that.

Before you order anything, take it apart, take it to the machine shop and have them measure your bore and crank. The current condition of your motor will determine how much it needs bored (.010-.030) and what rod you need. Just for your info, if you crank is worn and you can't use a .010 rod, check on eBay, I bought a stens kit for my motor there and they have available a .020 rod. It is my understanding that kohler only offers rods in standard and .010 undersized. Plus, the stens kits are much less $$ than kohler parts, what I have read, most are satisfied with their stens kits.

I looked at the stens kit i liked them.I'm going to have The machine shop do the rebuild they are a kohler dealer and can get the parts. I plan on rebuilding in the fall or winter when i'm not using it. The bore is nice and has is STD bore. If the crank is bad i have one thats is .010 under. I have parts motors if something is bad.