K301 for sale?
 

Hello I’m new to the forum. I have a IH Cub Cadet 125 that needs an engine overhaul. It burns oil so bad that it fouls the plug. I don’t have the tooling, knowledge or experience to rebuild my engine. I would have to take the bare block to a machine shop. I would rather buy a short block K301 for my 125 to keep it original. I’ve seen predator swaps but I just can’t do that to my Cub. Thanks in advance. Jay.

The problem with a used short block is the unknown condition it is in, unless you've seen the engine running and ran a compression test yourself it will always be a question mark and you could find yourself in the same position in the near future. I think it would be best to have an experienced hand inspect and rebuild it for you, not only will you keep your original engine but you'll know it should be good for another 30 years. If you feel comfortable removing and reinstalling everything but the flywheel and cylinder head you'll save yourself a few bucks that way.

Just my 2 cents, take it for what it's worth.

You make a good point. Hopefully, a fresh K301 will come up for sale from one of the experienced members here.

I don't recall anyone here trying this but it may be worth considering: http://shop.kustomlawnandgarden.com/...ired-CUB12.htm

Wow that’s awesome! Thank you for that information!

Where in Georgia are you located?

Zebulon, GA

Does yours still run? If you found a rebuild able replacement could you run what you have til you could go thru the replacement engine the right way then swap? I am in a similar predicament. But I have what Is hopefully a better used engine that is going onto my 129, while I rebuild it's original.
I have a few k301s here but only 1 is the "mounting ear-less" style that these cubs ran. The rest aren't. And I am using that one.
I have a completely rebuilt k321 (14hp) that has yet to be started since rebuild but not Cub spec. It's the original engine from my speery new Holland (predecessor to the Ariens GT)
I do have a rebuild able Cub spec 10 HP here (k241) but I always had a problem in my head, going backwards in HP even if the company built a version that way.
About 10 years ago I went to an auction for a guy who ran a small engine shop in the garage behind his house and one of the last lots to sell was a PILE of Kohler engines, and parts to build several, albeit all the blocks probably needed to visit the machine shop but it went cheaper than scrap price, and I often think back to that pile /and how many times since, if I'd had that pile it would have saved my a$$ on a machine. And the kicker? All were cub cadet compatible.

Yes mine still runs, but burns oil and smokes bad. Turns plug electrodes oily and fouls them in about five minutes then quits. Won’t start back even with a new plug. After it cools down to ambient temp, it will fire right up with a new plug. I did a leakdown test and I have about 50% leakdown. I pulled the cylinder head off and took measurements. Here’s what I found:

1: 3.377
2: 3.378
3: 3.3845

4: 3.3805
5: 3.3795
6: 3.380

Took each of the above measurements three times before recording. 1,2 and 3 was with the bore gauge perpendicular to crankshaft. 4, 5 and 6 was with the bore gauge parallel. Top of bore, middle of the bore then bottom. The cylinder is no longer truly round, it’s also a tiny bit larger diameter at the bottom. Max wear limit is 3.378”, max out of round is .003”, max taper is .002”. Looks like it’s time to just reach out to a machine shop. I’ll have to take a zillion pics and refer to the shop manual. I should probably check crank journal too. Thoughts guys?

Strip the block and take it and the crank to the shop.
They will/should tank it, fully inspect it, measure the clearances and let you know what need to be done and what size piston and rod to order.
Most kits I have seen and used usually come with everything you will need including new valves.

IIRC the guides are only about $20 more if needed.
I'd also take the valves and they will/can advise as to the condition and whether or not they and/or the guides should be replaced.

That's what my shop does. your experience may be entirely different.

Good luck

Note: Do not forget the shim behind the governor, take it out for safe keeping as well as shims that may be on the crank and cam.

Here is a link to the Kohler K=series service manual
https://resources.kohler.com/power/k...df/tp_2379.pdf