Craftsman GT6K

What would cause this thing to run really fat, fire oddly, and just not run smoothly in general? It always starts super easy, on the first few turns, but it just doesn't run right. There's a missing O ring on a jet but I don't think that would cause a problem this severe. There's something weird going on with it.

Oh yeah and im working on a foot throttle. My friend gave me this cool one so I'm trying to use it.

Yeah, if a jet isn't right, it will run bad.  Heck, if my tractors with adjustable jets are off just a half turn they will start running bad.

That pedal

I'm not sure if im keeping that pedal, it's not quite my style. We'll see.

Yeah its definitely shiny but man that's a cool find. Any idea what it came off of?

I think my friend got it from Wish but didnt like it. I have no idea what it's intended for.

It's that time




All welded. Not pretty but functional.


While waiting for the diff to cool i turned an arbor so i could turn the rear pulley to go to a 6". Gonna be fast. I think the taper was about 3°, don't take that for certain though.


No keyway but it fits snugly on the taper and I take pretty light cuts anyways so it's fine.



Hopefully tomorrow I'll get her back together and i can find a belt that'll fit. This thing might end up as fast as mutt. That'll be scary.

Why not just switch the gears around and lock it that way? People do it and it holds up great, and you can undo it.

I've heard some stories about that not holding up so well with hard use. It works for some people, but for others the diff assembly breaks and blows a hole in the case.

I flipped the gears around in my wheel horse, works good but I'd much rather do it a different way if I had to do it again. I think it holds up good for me because the gears are fully incased unlike a sears but I can turn one axle and theres some play before the other turns with it which I dont like.

I could've swapped the gears but you guys all know I'd break that in a heartbeat. I'm never going back unlocked anyway. Better to turn it into a solid chunk of metal so I don't have to worry about it.

Oh yeah i broke off two bolts in the case and have yet to address that issue. Ffs

nice locked Diff!

Wouldn't call it nice, it's functional though.

Cut the big pulley off, bored the little one to where it was cleaned off, turned the hub to a slip fit, peened it on there, and then welded it. Not bad on runout.




You know how many times i had to sharpen drill bits getting these things out? No threads left in the holes but theres room on the other side of the case for a nut.


Transaxle is back together, just needs the case bolts torqued down and refilled. I'm putting the old oil back in lol.

If you've never changed the oil, I'd put brand new in it. Just sayin'....

If anything's gonna kill this thing it's the diff coming apart not the oil. It's probably the factory oil tbh. Didn't have water in it so there's nothing wrong with it

She's a roller again. Working on a clutch now

I know it won't kill it, but I really don't care how good the oil is, unless I just put new in it or it's still golden, I always change it. Not telling you how to build your stuff, just telling you how I do it.

putting used oil in a trans U want to beat is the worst U can do....
I dont beat any trans thats still good without rebuilding it!

Yeah but i don't care about a 633, things are everywhere

633As R awesome transaxles! I'd do lots of dumb things to get 1!

@SebastianAlbrecht wrote:

633As R awesome transaxles! I'd do lots of dumb things to get 1!

You do lots of dumb things anyways

Took her for a top speed run. Runs nice when it's running outta gas. I have no idea why this thing runs this fat.


Drives really squirrelly, i really aughta find the tires I'm gonna stick with and start redesigning this front end.

I forgot i never showed what i did with the clutch

Just added a V idler and welded a tab on and drilled a hole for the linkage, pretty easy.

Ah the smell of a fresh new belt... Looks a little like mine did stock.

I'm surprised I've been able to use as many stock parts as I have.

I actually happened to be in town and just guessed on the belt size I'd need, luckily I guessed right lol.

Picked up this pair of 21x7-10s at the scrapyard for $20. As you can see, ones maybe ½" smaller than the tires of the same size on mutt, and one's another ¼" smaller than that (lot of left turns i guess). Regardless they're still the perfect size for front tires. I picked up some ATV tierods as well.


I really wanna do suspension on this rig but at the same time i really dont...ugh. I'd have to go back to the junkyard to get some coilovers or motorcycle forks (there was a ton of those there) and past then i don't even know... Monolink with a panhard(or two) and limiting straps would be easiest but i see it as a challenge to make it a tough as i want(i wanna slam on it like i would a regular mount. Plus with the cast iron axle, I'll have to bolt everything to it. Not an issue to drill, but an issue with rigidity.

J Spindles aren't staying anyways, going with a knuckle design over the stock spindle (at least thats the plan.

Drop some ideas you guys. I've not thought over suspension since I considered it on mutt.

No leaves, Allis.

Apologize for the multi post, but adapting motorcycle forks to work as regular (long ish travel) shocks sounds like a good project to me. Maybe cut the clamp off the bike and adapt it for a heim joint on top, and make something that bolts in place of the bottom spindle clamp on the bottom. Who knows. Possibilities are pretty endless.

Coilovers are always a good option, but not real short ones if you're looking for lots of articulation. In that sense I can see how the motorcycle forks would do good.

The only thing I wonder is would the sprung mass of this rig be too much for the shocks? I don't really know much about motorcycle shocks, but I assume if you get them from a bigger bike they'd have a higher spring rate. Do they usually have some adjustability to then?

A 1-link setup would be good and easy to fab up, but that setup has been dome a lot of times already. I think I'd be really neat to see something like a triangulated 4-link setup! Sure that requires some geometery work, but that's no big deal. Plus a triangulated setup would eliminate the need for a track bar.
I suppose the simplicity of the one link is hard to beat though..

One thing I really love about my Y-link setup is that it doesn't get in the way of anything under the tractor. Some multi-link setups like a 1-link, 3-link, etc. would make it a bit more difficult to mess with some stuff at the front of the tractor. Might not be a huge deal, but still a pain sometimes.

The strength issue shouldn't be as hard as you're thinking, just be sure to heavy enough steel and gusset every link mount so it'll stay solid and not break off or bend when you really get working the front axle. I've slammed or bumped the front wheels on my MTD forwards and backwards over countless objects, and surprisingly I have had zero issues with the link mounts or links themselves.

The only thing I can see not working out so great for you is the cast front axle, I'm thinking that might limit you to some degree.