Kohler 18 HP into a 20 HP??? same bore and stroke what do i need to do?

[clasicplug]

Hi I have a 1990 18 HP Kohler in a 8x8 Argo. Could you let me know how it worked out with the carb as I might rebuild my engine and if I can play with the carb to get more HP now would be the time to do it.

[spookum]

welcome to the forums clasicplug. when i get more information, ill let you know. probbably in a few weeks. make sure that you subscribe to this thread so it will email you wen i post again! you could also go down to the local kohler dealer/mechanic in your neck of the woods. They should be very knowledgleble, and if you find out before i do, let me know.

[clasicplug]

Thanks for the reply spookum. I'll see what I can find out.

[spookum]

Yah, i have taken it as far as i can with out sitting down with a pair of calipers to compare the actual interior bore size on the carb. Bolth sides need to be measured, the intake and the out side. They are *diffrent* part numbers, how ever it could be that they are actualy the SAME carb bodies (as evidenced by the exact same gasket sets for mounting.) I dont want to have to spend money on a new carb body to get 20 HP if all it is is jetting! The cams are the same for sure, along with the valves. All it can be then, is the way the machine "breaths" The 20 HP kohler is just some how getting more air/fuel than the 18 HP!

----->>>Friggin public computer!!! i hate adds.... if there was a way to get rid of it, i would!!!!!!! im sorry to all who view this post!<<<---------

i killed it

[msafi65]

Hey Spookum I found a complete Magnum manual available throught the databases in the local library. I downloaded the manual and the 18 hp shows 691cc and the 20hp 769cc. Same bore different stroke. Dont know if the carb swap will help or not .

[handbrake]

Sorry but I think there's a difference of 1/4 inch on the stroke if my memory ain't to bad. Giving the 2 HP.

[spookum]

dang it i think y'll might be correct. I was looking at newer model kohler engines, aka the ones you could buy today. I independently found this link:

http://www.kohlerengines.com/onlinec.../tp_2204_b.pdf

It is the complete rebuild manual for the kohler 18/20 hp magnums. Different ccs so i guess back to plan "b" get more power the old fashioned way by tweaking on the governor and mayhaps bumping the compression by slightly decking the heads. Thank you all for your participation! We will keep at it.

but the good news is that they have a 25 amp stator for it !!!! yeah! my winch on max draw pulls 30 so that is a heck of a lot better than 15 amp stator!