Kohler K Crankshaft Balancing.

[Ambush]

I just put the engine back into the 149 today. I rebuilt it a couple years ago, not long after getting the tractor and I left the balance gears out at that time. It does seem to shake a lot, but I don't really remember how bad it shook before. I've just found some info on a crank balance kit from an outfit called Kirk Engines. Its basically a weight you add to the crank, particularly if you leave the balance gears out. In his article he discusses differing weights in oversize pistons and pins. I did not compare the complete weight of my oversize piston to the stock one I replaced. He claims the added weight will definitely reduce vibration as they are "poorly" balanced to start with. I can make and install my own weight kit patterned after the Kirk one.

Has anybody static balanced a crank and piston set from a K series, particularly after boring oversize?

I'm probably going to fire it up tomorrow and if the vibration seems excessive, I may just pull the engine again and take it apart.

Just wish I had come across this a week ago when the engine was stripped and the pan and flywheel were off anyway.

[finsruskw]

I have one of those weights from Dave K installed on a 16 HP Kohler in my 1650 tiller rig.
At WOT is is smooth, I'm happy with it.

[Ambush]

Engine balancing used to be a common procedure for the performance guys during the muscle car era. Some voodoo involved or implied.

That’s good to hear you’ve had a positive outcome finsruskw. Firsthand experience is strong especially from someone who has sat in a lot of seats. Have you considered balancing others, or just not worth the money. I imagine the installation would be costly.

Does the Puller crowd balance engines for high rpm’s?

I believe there is a difference between “shake” and vibration. Shake being inherent in a one lunger.

[finsruskw]

Dave told me that installing the plate on a 14 HP Kohler would not yield much difference if at all.

[Ambush]

Good to know. If the guy selling them suggests no benefit, then that's very likely true.

I do wonder if the balance gears were more about counter vibration than balance. The engineers must have had a marketable reason to justify the cost to the sales execs.

[ol'George]

I agree 100% that balance gears offset vibrations.
But not much help balancing rotational unbalance.
Various engine manufacturers go about vibration issues in different ways than Kohler does with varying results, but any vibration reduction is good!