Craftsman GT Revive!

Well it's happening. The Sears was supposed to be my mudder for this wet season but it's no were near done and I don't wanna rush it. So I'm putting the Craftsman GT back together but with some changes this time. The Bearclaws and SunFs will be going back on it but there will be some drive train changes. No more belt twist!

I'm gonna be using the 40ci horizontal briggs oppy I got. It will need some carb work but nothing much.


This was the state of the tractor about a week ago when I started this.
I got the axle carrier moved forward again but this time I welded the front part of it in and improved the pivot point.. maybe.


I will be using a jackshaft so I can achieve good gearing with out sacrificing my clutching or having belt slip. I would love it if Mr. Modified could chine in. I know you have some experience on this one. Not everything is gonna be perfect. Just remember it's a toss together. I'll have more pics later.

Sweet deal! That horizontal shaft oppy should work well!

I can't remember if it was mentioned in a different thread... but is that oppy a 14hp or a 16hp model?

AllisKidD21 wrote:

Sweet deal! That horizontal shaft oppy should work well!

I can't remember if it was mentioned in a different thread... but is that oppy a 14hp or a 16hp model?

It's actually a 12.5hp. But it is getting a 19.5hp carb. So not sure where thats gonna get me. I wish it was a 42ci but ah alas.

Might get you somewhere in the realm of 16.

Whatcha using for a trans? 633?

RichieRichOverdrive wrote:

Might get you somewhere in the realm of 16.

Whatcha using for a trans? 633?

Yup. And over all the pulleys should be about 1 to 1 maybe a tiny bit higher.

Nice. The pulleys on my GT6k are like 7 to 6, so just over 1:1. Can't remember what speed i get out of it, I think the gps said 19 but 15 seemed more right. Governed btw.

(Current picture)


The trans is in and locked.(moose knuckle technique)


The egine plate is welded on and should work perfectly. It's 12 gauge I think. I started work on the jackshaft mounts I should have pics of that this evening.

I dont think Id use a jackshaft unless absolutely necessary, Mr. M has trouble shifting because of his, but its part of the design of his tractor so he build a nifty brake to help aid in shifting, I cant see any advantage of adding one for the hell of it. if you do keep the jackshaft then make sure your clutch is on the belt that goes to the trans, not the motor.

Creepycrawler wrote:

I dont think Id use a jackshaft unless absolutely necessary, Mr. M has trouble shifting because of his, but its part of the design of his tractor so he build a nifty brake to help aid in shifting, I cant see any advantage of adding one for the hell of it.

I was worried if might create shifting problems. Well I have some time and money invested in it so I'm gonna go for it. I was hoping the residents in the bearings would be enough to slow the shaft down. I might have to make a shaft break too. The other reason I like it is I can center the motor on the frame alittle better.

Maybe the bearings would have enough friction to slow the belt if you had like 2" pulleys lol. With the pulleys you'll be running they'll have a lot more momentum. You'd be better off running a straight belt like I did. There's really no room in these stupid frames for a jackshaft. Hardly enough room for a straight belt with the steering and clutch stuff there.

shifting shouldnt be an issue if you put your clutch on the Jackshaft to trans belt, and not the engine to jackshaft belt. if you do it the other way your basically adding a flywheel to the transmission in the form of two extra pulleys and a belt and the jackshaft and bearings.