4300 Range Shift Repair

   / 4300 Range Shift Repair #1  

jpinca

Member
Joined
Jan 18, 2010
Messages
42
Location
South San Francisco Bay, CA
Tractor
JD 2000 4300 HST 4WD
My range shift shaft is broken as is common with this model. This was a rental and the rental yard tried, unsuccessfully, to lock out high range with a strap across the shifter:
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and then again with a bolt:
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Neither seems to have worked and when the shaft gave way, it looks like the whole shifter linkage was tossed.

I bought all the parts online from JD Parts and it was pretty easy and the prices weren't too bad. Not good, but better than I feared.
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Instead of using the stock shaft (which might break again), I bought a piece of chrome plated 5/8" shaft stock from McMaster-Carr along with a couple of different types of shaft seals. I'll cut it to length and drill the two pin holes.
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Anyway, first course of action was to clean the tractor some so that I could see how it came apart.

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Part of this was from my infamous stuck a few weeks ago, but not all of it by a long shot.

The rockshaft cover was barely visible under all the years of crud.

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But after a little elbow grease and a water hose, I could see what was what and how all of this might come apart.

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Well, there's the part that caused this exercise
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The cover came off pretty easy. I ended up removing the SCV first to get better access to the pressure line, but it could probably be done without removing by using the proper wrenches. I don't have flare wrenches this big; I just had some adjustable that were too bulky to fit. Doing it over, I would remove the pressure line from the implement pump. The line hanging over the top of the cover just makes maneuvering the cover a little too awkward. The cover isn't especially heavy, but it isn't balanced and you have to remember that the lift arms rotate freely.
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There's the shaft we're going to replace
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Let's drain the oil and make sure the sump isn't full of clutch parts or something else

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The shift mechanism seems to be painted.

Looking around some more
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What is that?! It sure looks important.... Turns out it's from the PTO clutch release- one of four fingers. It looks like the pin just fell out as the mounts aren't broken and it looks reusable- good thing as you can't buy just the fingers, you have buy the whole hub. It seems a miracle it didn't pass through some gears. Heck, I must be pretty lucky.

Well, maybe not

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The PTO brake hub is broken and will need to be replaced. It is a $110 part, but it looks like I won't have to split the tractor to replace, just remove the PTO cover and slide it out the back.
This rental was used primarily with the tiller, so the PTO has been used/abused a lot. I'm not sure why the PTO brake isn't rigidly mounted. It can rotate 1/4 turn before it contacts the PTO bearing plate and stops the PTO shaft- hammering the part every time. It seems like this is needlessly hard on parts, especially an aluminum casting.

The range shift will have to wait until next week when I have all the parts to button things up.


<More to come...>
 
Last edited:
   / 4300 Range Shift Repair #2  
It almost hurts me to see how this 4300 was abused. You did get a good deal on it, Right did they pay us to take it? Good luck on getting it back in shape.

DR
 
   / 4300 Range Shift Repair #3  
This rental was used primarily with the tiller, so the PTO has been used/abused a lot. I'm not sure why the PTO brake isn't rigidly mounted. It can rotate 1/4 turn before it contacts the PTO bearing plate and stops the PTO shaft- hammering the part every time. It seems like this is needlessly hard on parts, especially an aluminum casting.

The PTO brake rotates freely a fraction of a full turn, as you found out,
in order to be able to attach the PTO drive shaft easier. Most tractors
I am aware of do not use a PTO brake at all, and that means you can
rotate the PTO shaft manually to get the driveshaft on.

I would consider (on the next 4300 I get) eliminating the PTO brake
entirely. Mine was in better shape, but I found a crack in one plate.

I can't quite make out the parts you found in the sump....are you going
to take photos of them cleaned up?

Anyway, I just got back from the Farm Show and just saw your pix. Good
luck.
 
   / 4300 Range Shift Repair
  • Thread Starter
#4  
I need to finish this post. I misplaced my camera and then....

Here's what the screen looked like. I'm not sure the screen had ever been cleaned although the fluid and HST filter were on a maintenance schedule.
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Removing the PTO cover gives access to the PTO brake clutch assemble.
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Another POV of the loose parts
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Broken clutch basket vs new
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Here's the new shaft installed and the seal I decided to use. It's just a 5/8" shaft seal from McMaster-Carr too.
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The new shift linkage installed, but the shaft hasn't been drilled or trimmed. I wanted to be sure I placed the dowel in the correct position for both the shaft seal and the shifter throw. Once I was happy with the position, I carefully drilled through the bellcrank into the shaft from both sides. Not perfect, but the best I could do without a drillpress
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Linkage adjusted so that the lever stop takes the abuse rather than the shift forks
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While I had it apart, I cleaned and painted the the back half. It looks better and should be easier to clean.

I've used the heck outta this tractor so far and this repair is working perfectly. I don't recall the exact cost, but subtracting the new fluid, I doubt I have $150 into it.

If there is no stress on the drivetrain, the ranges shift like butter. However it doesn't take much to bind the gears up and make the lever hard to move. I can see how this breakage can happen if you try to force the lever. Using the solid shaft as I did, I expect I've moved the weakest link further inside the tractor.
 
   / 4300 Range Shift Repair #5  
Good work.

Your misplaced camera isn't inside the tranny, right? :)
 
   / 4300 Range Shift Repair #6  
Thanks for the pictures and documentation of the repairs!:thumbsup:
 
   / 4300 Range Shift Repair #7  
I'm following up Egon...great thread and documentation!
 
   / 4300 Range Shift Repair #8  
Roy, I'm particularly interest as I have a 4200 JD. Selecting the range I want can be aggravating at times.:(
 
   / 4300 Range Shift Repair #9  
Roy, I'm particularly interest as I have a 4200 JD. Selecting the range I want can be aggravating at times.:(

I've got a 4400 so I'm interested too. My tractor is a sync-reverser though, not HST.
So far, mine shifts quite smoothly and I want to keep it that way. I bought Fluid Film (based upon several recommendations on TBN...I believe you were one of those recommendations, thank you very much!) to keep these linkages well lubricated.
 
   / 4300 Range Shift Repair #10  
Roy, I changed the hydro fluids so I've got several buckets of nice clear oil that I use. Pour some into a spray type dispenser plastic container from whatever and spray the areas in question.:D
 
 
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