HorseFixer 2,012 #1 Posted June 5, 2008 What are the differences between A K-90 and K-91 like on the internal parts pistons, rings, rods, main bearings? I have a few of these that will need refreshing. My Kohler manual only goes to K-91 I dont have manual for the K-90 Thanks Duke :whistle: Share this post Link to post Share on other sites
TT-(Moderator) 1,131 #2 Posted June 6, 2008 Without digging through a bunch of CD's of all the stuff I just cleaned off of my hard drive, I'm going to say that the K-90 and K-91 Kohlers are VERY similar internally. I know the K-90 cylinder heads have angled cooling fins and the K-91's are straight, and that the K-90 is governed at 3600 no-load rpm (3.6hp) and the K-91 is governed at 4000 no-load rpm. (4.0hp) I'll have to see if I can find the rest of the information when I get a chance. Share this post Link to post Share on other sites
HorseFixer 2,012 #3 Posted June 11, 2008 Thanks TT I have about 6 between the two that need freshening up Any info would be great! Thanks Duke Share this post Link to post Share on other sites