John Deere 4300 complete rebuild

[dfkrug]

Originally Posted by Wayne_H

Regarding the aluminum axle, I guess you are sure it is Aluminum and not cast? Cast is not always magnetic I think too.

Good luck, in a few months it will look better than mine!

The rear axle housings are definitely aluminum. I assume they are cast,
rather than forged due to their shape. The broken places are definitely
crystalline....my first clue they were Al was the lack of rust. Forging
aluminum is a more expensive process than even casting Al is. The
center section (gearbox) is cast iron or cast steel. It is VERY
magnetic. I use a neodymium magnet, BTW, and it even sticks to my
granite countertops. But not to Al, and most stainless steel.

As for my tractor looking better than yours, Wayne, you are only saying
that cuz you heard about my new shiny green hood and side panels.
You practically need sunglasses to look at them! :-)

[Whitey]

Thank you for all of your time and effort to document this re-build. I would never take on something like this..........but I find this fascinating to observe!

It is very interesting peering inside the components and seeing all the gears and shafts.........amazing how you push through this like it was nothing at all.

[dfkrug]

Originally Posted by Whitey

It is very interesting peering inside the components and seeing all the gears and shafts..........

I am glad you find this interesting and thanks for your support.

I love to take things apart to see how they work. Even more interesting is to
see how they fail, and sometimes how you can improve them. I am interested
in the design trade-offs made by the design engineer and the manufacturing
engineer. I guess that is the engineer in me.

I can justify opening up a broken machine, but it is hard to justify opening up
something that is still working fine. Many years ago, I did failure analysis as
a "device engineer" for a large semicondutor company....I find the mechanical
and hydraulic machines more interesting, and I can do actual work with them.
And many times electrical things fail and you never find out why.

[joes_427_vette]

Interesting thread. How do you figure out what to pay for these disasters as you have no idea how expensive the parts may get ? I learned long ago JD doesn't give anything away. Should be a nice unit when fixed.

[mjncad]

For giggles I took a magnet to my 4200's axle housings today, and sure enough they are cast aluminum as dfkrug has noted. I like aluminum; but for the life of me I don't understand why a more expensive and weaker material was chosen for a component that sees lots of stress from ground engaging implements and a frame mounted backhoe for those that have one.

I haven't had time to try and inspect the air intake duct.

[ampa]

Very enteresting to see what some people can do on damaging an exspensive piece of machinery, I have a problem with my PTO shaft moving inwards when I connect my Finishmower, when this happens the shaft moves in an inch or so and causes the oil seal to leak real bad, trouble with me is I'm afraid to remove the mounting plate to find out what the problem is, probley a clip missing or maybe a clip has dropped down inside, bein a gray market tractor finding parts would creat a huge problem, I give you credit where due that job you have taken on takes great skill, and my problem, would not be a problem to you I'm quite sure......keep up the good work and I to will be following this thread to the finished product........take care.....AMPA

[dfkrug]

Originally Posted by joes_427_vette

Interesting thread. How do you figure out what to pay for these disasters as you have no idea how expensive the parts may get ? I learned long ago JD doesn't give anything away. Should be a nice unit when fixed.

That is a good question. If I were a businessman who did automotive or
tractor repair to make a living, none of these projects could be justified.
This particular machine is very unusual for me in that every major area of
the tractor needs work. So I can look at the machine as a hulk with a
salvage value based on its servicable parts. Last year's B21 project had
a good engine and backhoe, which gave it considerable value as a parts
machine. This 4300 has some peripheral parts value (alternator, radiator,
front axle, rear tires, wheels, and probably the HST). I could not verify
anything, but I know my contact at the rental company very well. I also
know how much JD parts (and Kubota parts!) cost, so I figured the hulk
was worth only a thousand or so, and I would be spending at least $3500
for parts. I expect to put 50-100hr into repairs, so you can see that a
project like this is profitable only if my time is cheap. Finished, this machine
is worth $10-12K. I do plan to mount a new hoe to it with custom subframe
and add a PB loop, as well as one rear AUX valve. That will push the whole
unit up to about $16K in value. I get to indulge my creative energies on
those projects.

In previous months, I have looked at and made offers on a few other
project machines, but nothing came through. Some were skidsteers, and I
found numerous cheap machines out there. The big problem with the
least expensive ones was that the owner had already taken them apart.
A $3500 project Bobcat 753 becomes a $1500 project when you take it
apart and throw all the parts in boxes or leave it open to the elements.
Even if nothing is lost or damaged in dissassembly, I do not know Bobcats,
so I need to take the machine apart myself to analyze how it works, how
it failed, and how it goes back together. That's a big part of the fun, too.

[Brimstone10x]

Hey guys , the final drive/ axle housings on 4000 and 4000 tens are all alumium. The draft arm mounts brake all the time . the mounting bolts bosses crack with a B/H. and under corrosive condtions they can just about disindgreat . However I have seen these units with 3500 hrs on them. John JD service tech.

[kebo]

I checked the axle castings and the middle casting that houses the transmission with a magnet yesterday on my 790. The magnet stuck, so apparently they were cast with a ferrous metal.

[mjncad]

Originally Posted by Brimstone10x

Hey guys , the final drive/ axle housings on 4000 and 4000 tens are all alumium. The draft arm mounts brake all the time . the mounting bolts bosses crack with a B/H. and under corrosive condtions they can just about disindgreat . However I have seen these units with 3500 hrs on them. John JD service tech.

Do you replace the housings or weld them as dfkrug is planning on doing?