# X300 won't climb hills



## Joneck1 (Mar 18, 2016)

I know there's plenty of info out there about the K46 being known garbage, but my situation is at a crossroads and I need some advice. Here's the deal:

I bought a used JD x300 that originally came from a JD dealer, second year of owning it now and it won't make it up the big hills that it lumbered up last year. My GT235 was way better on hills. X300 engine runs great, so I've got to do something with the trans.

I also own a GT235 with a blown engine and a good k71 trans, just sitting.

Do I:
A. Replace the oil in the K46 and see if that helps
B. Rebuild the K46
C. Put the x300 motor into the GT235
D. Put the GT235 trans into the x300

I'm a mechanic, but I'm also building a house right now so my time is tight. I'm leaning towards the fluid swap but I'd love to find some tech info on the swappability of these components. 
Thanks


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## HarveyW (Sep 15, 2014)

Howdy Joneck1,

Welcome aboard the tractor forum. 

All of your options are viable. In reading about the K46 transmission on the internet, it is not a question of "if" it is going to fail, it's a matter of "when". Yours has reached the latter stage. Junk. It's amazing that JD would produce such a low quality machine.

I guess I would go for options C or D, whichever is easier and more attractive to you.


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## Joneck1 (Mar 18, 2016)

Thanks Harvey. Do you know of any good tech info sources for swapping the trans?


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## jhngardner367 (Apr 5, 2011)

Both these transaxles,are the narrow type,so fitment should be ok. 
the K46 was originally intended for the rear-engine riders,so why JD would put them on the LX,or X series is beyond me !Maximum tire size rating for it is only 18" .
The k71 is designed for the 23" tires,and has 1" shafts.
Measure the width of both,to make sure there's no problems,and Plan on changing the rear wheels,and tires.


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## Joneck1 (Mar 18, 2016)

Thanks JH!
I'm gonna swap the K71 into the x300. 
Rainy and cold here today so I'm gonna get the garage cleaned out and ready it.
I still haven't seen any tuff-torq swap info, but I haven't looked too hard yet. I'd like to find a tech article or at least a table telling if and how the swap will work.

When/if I do the swap I'll take pics and try and do I write-up for this site. Unless I find that write-up already done somewhere.


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## jhngardner367 (Apr 5, 2011)

I don't know of any tech articles on these swaps. 
The main things to Look for is the width of mount pads,Clearance for the pulley/fan,and the connections for the forward/reverse pedals.
If these are ok,it should work.


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## Joneck1 (Mar 18, 2016)

The swap is underway.
The mounts, belt, and linkages "almost" fit.
The Gt235 does not have a removable rear clip, the x300 does.

I've got the x300 rear clip laid out to do some cutting and welding this morning. The K71 sits too low, gotta move it up in the frame, and back some too. 

May have to use the K46 fan and pulley due to the height issues. Gonna try not to though because the k71's is a little bigger.

We shall see.


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## jhngardner367 (Apr 5, 2011)

Should work,ok. 
If I can put a Briggs twin in an old Bolens,this swap should be fairly easy ! LOL!
keep up the pics.


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## Joneck1 (Mar 18, 2016)

Made quite a bit of progress today.
Everything is lining up pretty well with some easy mods. 

I'm taking pictures as I go.


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## Joneck1 (Mar 18, 2016)

*It lives!*

I got the swap done last weekend. It really wasn't too terribly hard either. I've cut the yard once and it sprints up the hills! The K71 has a ton of speed and torque compared to the K46.
The big changes that had to happen were almost all to the x300 chasis:

1.Cut off and reposition the mounting pads on the removable rear frame clip.
The K71 sat too low and forward in the K46's old spot to allow the drive belt to align. It needed to move up an inch and back about two inches. I made lines on the clip, cut out 1/2", and overlapped another 1/2" with the pad, drilled and bolted on, then re-welded. Also had to waller out the mounting holes some to get the K71 bolted in.

2. Make an access hole in the back of same clip. In order to access the K71's roll/drive disconnect, oil filler, and allow more cooling air flow, I cut a big rectangle out of the clip.

3.Straighten brake linkage. The brake levers are on different planes between the K46 and K71 but a simple tweak of one bend on the linkage allows the K71 to mount and function.

4. Make or find bushings to take up slack in brake and throttle linkage trunions. The trunions on the x300 are a little smaller in diameter than the K71 needs. I just took some thin sheet metal and made a split ring, then ground it down to fit. It was easy for the throttle trunion, but of course the brake trunion was a different size and required a lot more grinding to fit.

5. Shim up the K71 pulley and fan. I put a fat washer under the K71's pulley to bring it up a little more for alignment. 

That's about it really. Make sure you have all the linkages adjusted so that they make full travel and that your belt isn't rubbing anything too bad.


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## jhngardner367 (Apr 5, 2011)

Great conversion! Glad it went well !


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