Something must have broke inside the engine
 

Hi,

I was mowing with my 129 (which a few months ago had significant work done to it including a valve replacement and other engine work) and I heard something break - figured it was a mechanical piece underneath the tractor somewhere, but checked and all is fine. When trying to start it, all that happens is the front pulley is turning but there is obviously no compression. If I look through the site hole that is used to check the timing - that part is turning. Any thoughts on what this might be? Obviously, the head has to be pulled to see if the piston and valves are moving. Not sure how much more money I want to put into a 45 year old tractor. I could get a rebuilt Kohler engine for it (have been wrangling over this for the past few years), but just not sure that would be the best decision. If I decide to replace the Cub, any suggestions on what to buy?

Sounds like you broke a rod.

I rebuilt Kohlers and sell them. I've got 20 years experience as an engine builder. I've got a K301 I can ship you.
http://www.onlycubcadets.net/forum/s...ad.php?t=52504

I would fix the 129. Good tractor. Cheaper to fix than replace it anyway.

Yes. If your engine is shot, put a rebuilt Kohler back in this one or get yours rebuilt (if it is salvageable. I don't know what all is wrong, so it may be bad, it may not). You're going to spend a pretty penny on a good certified Kohler, but it will be a cheap investment to get another 45 years out of it. Also, your machine isn't going to depreciate in value. They only made so many, and each year, fewer and fewer are alive. Rebuilding this cub will be an investment, but one that will hold it's value. Buying a new machine will get you back riding, but do the right thing and save this cub.:beerchug:

Pull the spark plug and put a long wooden dowel in the hole and turn engine it over. Then tell us how much it goes up and down, if at all.

I would thing that turning the engine over during this test should be done "by hand"..?:bigthink:

yeah....I'd think by hand would be best. I'll do that, although probably removing the head is the best way to see what's going on. Since the shaft coming out of the engine into the trans appears to be rotating normally, then it almost has to be a valve or piston/rod issue.

:):):):):)The cub might be able to get an additional 45 years of longevity, but if so the total span of that surely won't be with me!

Pulled the head...both valves appear to be working normally, but piston doesn't move.

You can't do that on a K series Kohler. The spark plug is over the valves, not the piston.


It broke the rod. Motor is done. :Sorry:

Broken connecting rod

Talk to Jon about one of his rebuilt engines :beerchug: