JC 1965 1,532 #1 Posted August 12, 2011 :D need some help here. I recently got a K-301 free, it runs fair. I pulled the head and saw .030 stamped on the piston and the cylinder has groves worn in the sides. My question is, Should i have it bored out and a sleeve put in or have it bored out to 3.500 and get a standard size piston for a 14 hp kohler K-321? I read somewhere that a 14 hp kohler K-321 is just a K-301 block bored out to 3.500. Could someone give me some advice here, the inside parts of the engine are new to me. Opinions welcome!! Share this post Link to post Share on other sites
TT-(Moderator) 1,162 #2 Posted August 12, 2011 I know you can bore the thick-wall K301 blocks out to K321 bore sizes (includes oversize) but I don't know if all 301 blocks are thick-wall castings. You will have to change to a K321/K341 crankshaft though - they are balanced differently due to the heavier reciprocating assembly. If you try using the lighter 301 crankshaft, it will vibrate excessively. Share this post Link to post Share on other sites
305 380 #3 Posted August 12, 2011 if i was in your situation , my first thought would be is how thick the cylinder wall is. standard bore of the K301 is 3.375 , so you would be boring it 1/8" or .125 i don't know if the factory K321 block has a thicker wall to allow that. maybe others here will know. Share this post Link to post Share on other sites
JC 1965 1,532 #4 Posted August 13, 2011 I know you can bore the thick-wall K301 blocks out to K321 bore sizes (includes oversize) but I don't know if all 301 blocks are thick-wall castings. You will have to change to a K321/K341 crankshaft though - they are balanced differently due to the heavier reciprocating assembly. If you try using the lighter 301 crankshaft, it will vibrate excessively. Thanks for your help Terry. I'll probably check with the machine shop to see how much it will cost to get it bored out and sleeved. Share this post Link to post Share on other sites
JC 1965 1,532 #5 Posted August 13, 2011 if i was in your situation , my first thought would be is how thick the cylinder wall is. standard bore of the K301 is 3.375 , so you would be boring it 1/8" or .125 i don't know if the factory K321 block has a thicker wall to allow that. maybe others here will know. you're right 305. .125 is a lot to bore out so i will check on a sleeve . I really want to save this old K-301 if it's within my budget. Thanks!! Share this post Link to post Share on other sites
