Thor27 835 #1 Posted November 29, 2021 (edited) Recently picked up a m18, had hopes of a quick de carbon, reseal, and put to work, unfortunately this appears to be a very high hour unit. It's std, no cross hatch, bit of a ridge. It also has a badly burned exhaust valve on #1, and the seat and guides aren't pretty. Looking for advice. If I go for a full rebuild with machine work, pistons and rods, could i buy a used m20 crank and build this as a 20? Is there a downside other than the big one (cost)? Other option is looking for a good running mv18 and robbing pistons, rods, and jugs. Imho the vertical shaft tractors don't seem to last as long as their kohlers do. What would you do? Edited November 30, 2021 by Thor27 Share this post Link to post Share on other sites
953 nut 59,917 #2 Posted November 29, 2021 1 hour ago, Thor27 said: Other option is tight is looking for a good running mv18 and robbing pistons, rods, and jugs. If the seller will let you do a compression test before you pass him some cash this would be a smart way to revive your engine. 1 Share this post Link to post Share on other sites
pfrederi 18,664 #3 Posted November 30, 2021 I just finished a complete overhaul of an M18. It is an expensive project. Frankly i would not do it again When one of my KT17s die it will be a re power.... I know everyone says rebuild it an it will last another 40 years...but OEM Kohler parts are not available for most things and those that are are priced out of reach. So how long will after market rods rings a an valves last??? Machineshop work is double the normal cost (2 cylinders...) Just initial parts and machine shop work I was in for $750 add some more parts I had to get and we are at almost $900 and again most parts are after market. Yes she starts and runs... but who knows how long. 4 Share this post Link to post Share on other sites
Thor27 835 #4 Posted December 1, 2021 (edited) I was all ready to go for the used MV route, Until I re read your build Paul, now I'm back on the fence because yours looks so good inside. I was spoiled when my last magnum went together because I didn't have to replace hard parts. So, No Lash on this valve so it was slightly open for lord only knows how long. You could shave with this thing... Edited December 1, 2021 by Thor27 Add pics from phone 1 Share this post Link to post Share on other sites
pfrederi 18,664 #5 Posted December 1, 2021 10 hours ago, Thor27 said: I was all ready to go for the used MV route, Until I re read your build Paul, now I'm back on the fence because yours looks so good inside. I was spoiled when my last magnum went together because I didn't have to replace hard parts. So, No Lash on this valve so it was slightly open for lord only knows how long. You could shave with this thing... When you start looking for valves be advised at some point in production they changed from 45 to 30 degree 1 1 Share this post Link to post Share on other sites
kpinnc 14,630 #6 Posted December 3, 2021 (edited) On 11/29/2021 at 5:38 PM, Thor27 said: Other option is looking for a good running mv18 and robbing pistons, rods, and jugs. Imho the vertical shaft tractors don't seem to last as long as their kohlers do. Brian Miller's site says converting Mag twins from vertical to horizontal is easy. Might be worth exploring on a cheap vertical engine for parts? Edited December 3, 2021 by kpinnc 2 1 Share this post Link to post Share on other sites
