14hp Tecumseh to 25hp Kohler help

[NathanK]

I recently purchased a old maxll with a Tecumseh 14 hp engine that does not run. The trans had a stuck plunger. It has sat for years.. I have always wanted one of these machines and this one came my way and for a very few hundred bucks I figured I'd never get the chance again. Long story short I removed the engine and transmission. I have freed the plunger the bands seem to be in good shape it shifts freely. I have replaced the fluid and added friction modifier and will be installing back into the max ll this week.Next I traded some wheels for a 25hp Kohler command the crankshaft was to big for the pulley so my friend run it down on a lathe and machined a new keyway so that it all fits and I have put new rings and gaskets. I would greatly appreciate any insight, suggestions from anyone who has done this as to what I'm in for as far as modifications or trouble I will face installing this engine.. that is NathanK

[dirtdobber]

Congratulations on your first machine. I don't know about what trouble you may have but I can tell you some things you need to do. Post some pics so we can see what you have.

Check your chains and bearings. With the engine and tranny out now is the time to replace bearings and chains if needed. Get all six wheels off the ground and spin them. Listen for clicks and pops and try to move the tires up and down for slack in the bearings.

When you mount the engine, it needs to be adjustable so you can fine tune the belt tension. I think on max machines the engine sits above the tranny and you can shim the engine to get more belt tension. If so that's good. If not, figure out a way to make it adjustable.

Also, with a different engine your belt length will probably have to change. If you have to
fabricate your engine adjustment you need to start with the correct distance between the engine and tranny. Report back on what you have. Good luck.

[NathanK]

Copy, I will and am doing those exact things. As it is I got the trans put back together and now one side does t shift properly so I'm gonna take it back apart tomorrow to see what's up. It will shift from neutral one way but not the other.. the other side shifts as it should.

[NathanK]

The plate below the drums was in with the beveled edge the wrong way. Go figure. I reckon that answers weather it has been taken apart before I got into it.. nevertheless. I hope to get it back in my machine by the weekend..

[Noel Woods]

Most of the Max 14hp machines had hollow axles until fairly late in the production years. The power of a 25 Kohler will soon show you where all the weak areas are. I have such a machine and upgraded to 18hp only as a work around. If your's has hollow axles, the upside is that you can manage to shape those back to normal without too much effort if they get bent. Solid axles, not so easy.

Does your's have discs or drums in the front?

[NathanK]

It has drums

[Noel Woods]

Somewhere in 1995 they switched to discs usage from the factory, your's must have been produced prior to then.

[NathanK]

the serial number is 6493 idk what year that makes it. Early 80s I reckon.. I'm looking forward to getting the trans back in it this afternoon.

[trevorc5505]

Do you have any pictures of this whole operation? I'll most likely be doing a similar swap soon.

[NathanK]

I will get some pictures soon. This whole operation has been slow cause I have rebuilt the Kohler at work a little everyday on my lunch break and I tinker on the machine at home what I can before it gets dark... To that end I've made steady progress. My next task is to mount the engine on the brackets that came with the 14hp. Best I can tell I will just drill knew holes to move the engine to the right in the tub cause the Kohler is wider than the old Tecumseh.I have big dreams of getting it rite at the shop and bringing it home and fitting the first time... It could happen. The Kohler is just a little bit taller at the shaft maybe a inch give or take. So I'll let you know how it all shakes out. But so far it has all been pretty straight forward. I'm not sure what to do about exhaust yet that I feel is gonna be my next big issue in that I just don't know how things will fit and I don't yet have any exhaust for the engine or what I will have to modify or engineer to get it in there... The Kohler is a lot lighter than the old Tecumseh by far though.

[NathanK]

I got the engine placed in the max this evening. It fits like a glove, couldn't have asked for it any better. I used all the old mounts from the Tecumseh I marked where the clutch was one the bar motor mounts and drilled new holes so the Kohler would line up the same and sure enough it all fits.. got some wiring and plumbing to do but can't wait to get this thing moving..... Has anyone used a electric fuel pump on a Kohler 25hp?

[NathanK]

I have it all together running and rolling.. this is my first 6x6 I've owned. It's the first one I've ever looked at in person for more than a few minutes. It definitely the first one I've ever got to operate.. and it's the best I've been stomping all over and through everything all weekend and had a blast. There are still a few things I'd like to do to it... All in all it is gonna be a nice little rig... Thank you guys for having this website it has been very helpful and for sure seeing what you guys are doing have me a lot of motivation to get it done.. and without having to spend lots of money.. (at once, still got things I want to do to it now) again thanks and if there are any questions I can help anyone with just ask... Nathan K

[max4]

congrats, sounds like that went extremely well and you nailed the details better than i would have for sure.
I remember my first trip into the creek with a max, it was and still is very cool. You certainly deserve to have blast romping around thru everything you can with it after all that work. You won't know what it'll do till ya get it stuck!
Only question at the moment is hows it look, got any pics you might be able to share?

[NathanK]

I just haven't figured out how to post pictures... Maybe some advice in that area would be helpful

[NathanK]

I think my belt is to tight? I'm running the kohler25 horse with all the original clutches from the Tecumseh.i have to open up the pulley on the t20 to get it on and it rides at least a inch or better down in it at rest.. can anyone suggest a belt.. will the belts I see online for the Briggs motors be bigger?