Please put your 2018 WHCC Show Pictures in the new 2018 WHCC show picture forum. Enjoy the show!

Jump to content
Mike Nelson

Tired old Kohler K301 needs TLC

Recommended Posts

Hello to all. I have a 1973 Wheel Horse 12 automatic in pretty good shape. It has been in continuous summer use since the day it was new. This machine is only used for lawn cutting in Wisconsin. It spends it's winters inside of a garage that is attached to my house. It has never been left outside when not in use. It has the famous Kohler K series engine, (K301). Other than a replaced fuel pump, and standard tune up items, this tough old engine has never been worked on internally. Over the last few years, I can tell it is has lost some power. It also has begun to use oil (sae 30w) at an increasing rate, Although no signs of smoking. It is also seeping some oil out of the governor shaft bushing.  Because this is such a tough old tractor, and the fact that I have a spare hydro unit, I have decided to rebuild this engine. Heck, it's already got 43 years of use from this tough engine. I am not wanting to just "THROW some rings in there" and call it a rebuild. OH NO! I will do this the right way.


I would love to just get a new Kohler short block and call it a day, but I know they are getting rare now especially trying to match up with my unique spec number. So I will have to do a complete tear down and rebuild. I will leave no stone unturned. I have no knowledge of machine shop procedures, but I should have no problem, to dissemble, clean, have machine shop work done, then reassemble.  The reason I posted this, is to ask if anyone knows of a genuine small engine machine shop, without a bunch of high school kids learning how on my engine.  I have tried in the past to have quality work done at machine shops, and I have discovered that with all my ignorance in this area, I was more informed than most of them. The one place I came to trust is long gone now. I always run this engine full blast when cutting the lawn (wide open throttle) that is why I would like OEM Kohler parts inside. I know getting OEM for something this old will not be easy, but I am much more concerned about finding a trusted and competent machine shop to do quality work. I can find do it yourself machine shop hacks anywhere, 


MOST of the members here are well informed, caring and dedicated folks who care about preserving the classic old Wheel Horse. Can you please give me your thoughts on undertaking this rebuild?

Thanks so much 

  • Like 2

Share this post

Link to post
Share on other sites

:WRS:           Don't live in your area so can't come up with a specific name of a shop. I would suggest talking to the owner/managers of some equipment rental stores to see who they use; they want the work done right and they want it done promptly.

Take a look at this recent thread on engine rebuilding, it will be a good resource.

Good luck and keep us posted as you go along.

  • Like 1

Share this post

Link to post
Share on other sites

Talk to your local mechanic shop and see who he uses for his machine shop work. He won't take his work to a machine shop he does not trust to do his work. I have done a dozen or so K series kohler rebuilds with aftermarket engine parts with great success. Besides a quality machining job and a clean assembly will make a quality engine rebuild. And :WRS:

  • Like 3

Share this post

Link to post
Share on other sites

 I really cannot say what a rebuild costs, but one way to go is just buy another Horse with the same engine series. My addiction started with a Kohler 10 Raider of 1972 vintage. I bought a second tractor much like yours and a third 12 horsepower manual transmission. What i will probably wind up doing is pick the best engines and sheet metal from all three to make two sweet tractors and another running tractor that will be sold.  I have a Raider10, an Electro 12, and a c-121-8. that will be mix and match.If they all fit together like I think they will.


 Maybe you could do the same. Find a decent runner that may have other issues and swap engines so you can take all the time you need to get your 301 the way you want it.. You certainly do not want to run the risk of working your tired engine and then throw a rod through the engine block. I only have $775 in all my stuff, but I am careful and try to learn from my mistakes.



  • Like 1

Share this post

Link to post
Share on other sites

There are a lot of garden tractor pullers in Wisconsin - look some up and find out who they use , any builder that can handle doing mods to that extent on a Kohler engine knows their stuff . I'm lucky , got an old school machine shop nearby that specializes in these engines and will only use Genuine Kohler parts , never anything aftermarket . His prices aren't bad at around $500 if the crank is good...


  • Like 1

Share this post

Link to post
Share on other sites



The engine you describe might not actually need a machine shop, as there's no catastrophic failure. I'd tear it apart, and do some inspecting. If it's not blowing oil/smoking, perhaps a hone, valve lapping, some new seals, new rings, and you're off and running. Obviously you won't know until you get there, but all new parts might not be nessasary. Good luck with it. You've found the right forum.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By porschpow
      Good Morning everybody!
      I am in the process of sharpening the blades for my mowing deck (Model 78360 - Serial 7904987) and I noticed that the deck has a crack in it right where the bracket to the mounting hardware (to the tractor) is. SO I know I have to get that repaired.
      But while I was at this, I thought I could do a good quick once over on the deck to make sure I am ready for the season.
      What I would like to do is the following:
      Change the bearings for the spindles (or pack them with more grease)
      Get new rear tires (since they squeak)
      And that's about it
      If anyone here thinks I should do anything else, I would love to hear it!
      Where does everyone get the hardware (bearings, wheels for these rebuilds?)

    • By 12 hp Kohler
      I have a kohler k321. I picked this engine up at an auction and I don’t know it if it runs or not, I haven’t tried and don’t have the time. It has good compression and is complete. It would work in a wheel horse but would need to be wired differently. Pm or email me for details I will try to get back to you ASAP. The engine is a little dirty and could use a hose down. I can haul the engine to the big show. 

      HH100-115095B fuel pump I need a rebuild kit for this fuel pump does anyone know where to buy one. it bolts to the side of the engine
    • By Bill D
      I have a K321S, Spec # 60424, S/N 14169017.  I was counting the cooling fins on the rear of the engine and noticed that it has 13 fins.  I read somewhere that 13 fin blocks were more sought after thatn 12 fin blocks.  If so, why?  Also is it possible to have a 13 fin K321, or did someone possibly change the cover in the past?  Also is it possble to tell is this engine has balance gears from the numbers?  I have read that some engines did not have them.  Thanks 
    • By WVHillbilly520H
      @WHX14, @Achto, here's the offending culprits of Kohler K161 fuel tanks on the CC ORIGINAL, that keep breaking the solder around the fuel outlet bung, any tips on repair would be greatly appreciated, as well a couple pics of the original engines/tins and the tractor with few upgrades I'm planning with the repaint, besides the K181 with ring gear starter out of a Gravely, Jeff.