richmondred01 2,301 #1 Posted December 28, 2019 (edited) Over the years people have asked me the difference in the 12 vs 13 fin k341. I happen to have one on my bench right now just getting finished being rebuilt so I thought I would take a minute and show some photos and explain the difference. They are rather uncommon to find however, this is one that is a wheel horse spec engine which is even more uncommon. This is from Brian Miller’s website: The 12 fin Kohler K-series and Magnum engine block models K341/M16 (16hp) have an indentation in the cooling fins (clearance for a straight oil fill/dipstick tube) and a threaded hole towards the bottom of the cylinder. This block have a thinner cylinder wall than the 13 fin block. This block is most common, and used mainly for light duty lawn and garden equipment applications, and can be safely bored up to a 3.825" [pulling] piston without danger of seriously weakening the integrity of the cylinder wall. But the 13 fin Kohler engine block model K341 (16hp) have a thicker cylinder wall. This block is somewhat rare, and used mainly for heavy duty industrial applications and can be bored for a much bigger [pulling] piston, up to 4-1/8". Both blocks originally have a STD cylinder bore of 3.750 Edited December 28, 2019 by richmondred01 1 2 Share this post Link to post Share on other sites
ebinmaine 71,792 #2 Posted December 28, 2019 Were the 13 fin blocks used in any particular tractor? Share this post Link to post Share on other sites
richmondred01 2,301 #3 Posted December 28, 2019 (edited) This is only the second one I’ve encountered off a wheel horse. Most I’ve seen and rebuilt were on more industrial equipment like the Vermeer chippers and log splitters. This one was on a c160. The spec on the blower housing is wheel horse. Edited December 28, 2019 by richmondred01 1 1 Share this post Link to post Share on other sites
MikMacMike 489 #4 Posted December 28, 2019 were there differnces on fin count with the 321 or any other k series? Share this post Link to post Share on other sites
richmondred01 2,301 #5 Posted December 29, 2019 10,12 and 14 hp Kohlers have 13 fins. The vast majority of 16 hp have 12. 1 2 Share this post Link to post Share on other sites