John Deere 4300 complete rebuild

[dfkrug]

This thread is going to be a little different from my others. This time I am
going to post updates long before the project is finished. That way, events
are fresher in my mind, and I think this one is going to take longer than my
previous rebuilds. Some things may not work out as expected, too. (Is
that engine going to be rebuildable, or is it too far gone?)

As before, I welcome constructive comments and questions. As with most of
my projects, this is an interesting learning experience for me, especially in
that it is not exactly like any of the others, whether it is a tractor, car,
m/c, building, etc. Hopefully it willl be interesting to anyone who wastes
some time reading this and looking at my photos. Indeed, the project must
be different enough to interest me, too!

I have been looking for skid steer projects to expand my horizons, but I have
not found exactly the right deal. I was really fussy, I guess, in that I wanted
a Bobcat or Mustang or JD250 or whatever that had problems, but was not
already in pieces.

Anyway, my pals over at the rental yard made the mistake of showing me this
beauty: a 2000 JD 4300. Is is REALLY bad...lots worse than last year's B21.
I have done a bunch of rental tractor rebuilds and this one interested me
because it has a modern hydrostatic tranmission, which I want to take apart
to compare and contrast to the Kubota HST I recently rebuilt. It also
represents the recent evolution of JD's compact tractors, and this one is not
all Yanmar-built. How well does it compare to the earlier Yanmars? Finally,
this tractor is VERY close in every aspect to other 30+hp 3000 lb. CUTs from
Kubota, NH, and Kioti. (L3130, TC35, CK30) How do they compare?

Anyway, here are pix of how I found this poor tractor. Note the missing
parts: hood, seat, FEL valves, etc. If you look closely at #3, you can see
the instrument cluster lying on the floorboard, along with a 3-pt arm, and
a loose FEL cylinder. Tires are flat an wheels are off. There is a very
hefty JD hood protector....I don't think it worked. Reports are that the
engine is dead, and I can see a bent FEL cylinder rod and a broken axle
casting.

Next time: I get the beast home.

 

[mjncad]

Good grief! That poor tractor was beat to he11.

Since I own a 2001 4200, I'll be following your story with interest. Fortunately mine leads a very sheltered life.

 

[Farmerford]

I look forward to following your adventure.

At the local rental yard that one would still be in service; in fact, I think the same maintenance guy worked on the last Ditch Which I rented.

And on Craigslist it would be described as a "great project tractor" that was "running when stored".

Since you are attracted by a challenge, can I send you the barrel swing motor on my old JD backhoe?

Seriously, I always learn something from your posts and will follow this one closely.

 

[Scooby074]

Good luck on the rebuild. Looks like your going to have your work cut out on that one. Poor thing looks like it should have been taken out back and shot.

On the upside, your going to have a nice machine for not too much money (hopefully) when your done.

 

[dfkrug]

Since you are attracted by a challenge, can I send you the barrel swing motor on my old JD backhoe?

I don't know what that is, but it sounds interesting. Deere CUT fans should
take note that in 98 when this new series of tractors came out (4200/4300/
4400), the company integrated subassemblies and parts from many different
companies, not just Yanmar. This caused numerous failures and unofficial
recalls. This unit is one of several (7 or 8, I think) that replaced the JD955s
at this rental company and Deere had to do a bunch of warranty service on
them. More on that later. Needless to say, every weak point in these
machines was found by the renters!

I posted another thread the other day about some broken 4300s:

http://www.tractorbynet.com/forums/john-deere-owning-operating/146426-jd-4300-broken-half.html

 

[dfkrug]

These pix show the tractor after it was brought home on a rollback
truck. The place I bought it from sort of put it together with the parts
they could find, so at least it could be moved. Numerous parts had been
taken off to fix other 4300s that were in the active rental fleet. Since the
range shift was broken and the transimission was in gear, I had to pull
the tractor off the truck deck.

The 2nd photo shows the back end of the tractor, and the broken right
axle housing. I was surprised to find out this casing is cast aluminum....not
a good design decision, IMO. The lower 3-pt arm attachment has pulled
out. The middle section is cast iron or cast steel, which is the opposite
of the earlier 955, which had Al center and cast steel axle housings. The
Kiotis I have owned, and some of the Kubotas used all steel back there. I
would hesitate to buy a tractor this size with Al axle castings. (I do plan
to mount a backhoe on this tractor.)

3rd photo shows a bent loader cylinder rod....these guys are only 25mm
in diameter! Too small, IMO, which is supported by the fact that many
many of these have been bent. Attempts were made to protect them
(see the green bracket?) with limited success. This is the 420 FEL;
maybe the larger 430 FEL is more robust?

Finally take a look at the the two independent hydraulic pumps....no
flow divider is used, which IS the case on a lot of other CUTs this size. Nice.

 

[mjncad]

I'm surprised the rental yard spent the extra bucks to buy the hood armor kit.

 

[dfkrug]

I'm surprised the rental yard spent the extra bucks to buy the hood armor kit.

The hood armor is made by JD, but I can not find it in the parts book. There
are several "rental upgrade kits" that are not described, however. This
hood armor is awesome.....it must weigh at least 100 lb!

The new plastic is green all the way thru (ABS?) and not easily fixed when
broken. It replaced the earlier fiberglass hoods, which were aften smashed
but were easier to fix. I did a few on the 955s. The new plastics are
sourced from a plant in the US somewhere, according to the box the new
hood came it. I prefer sheet metal body parts, and I doubt the rental yard
will ever buy any tractor with plastic body panels again. (BTW, I have been
encouraging them to consider the Bobcat version of the Kioti DK35SEHST
because it has metal panels, no clutch, local service support, and very
aggressive pricing.)

 

[vic4news]

Very interesting. Looking forward to following your progress.

Vic

 

[pat32rf]

Judging by the paint I believe that the cylinder rod got bent when something was jammed UNDER it and the cylinder rod tried to crush it. Not surprized it bent.
Similarly the rear 3pth bracket seems to be chewed up from the pin not being fully in place during operation. These things are not really idiot proof....

 

[Kernopelli]

Wow, talk about "rode hard and put up wet".
As others have stated, I'm looking forward to seeing the progress. I was impressed when you did the B21 resto....this is going to be akin to raising Lazarus from the dead..... I guess that would make you the tractor Messiah. COOOLLL!!

All jokes aside, how are you going to address the aluminum (What was JD thinking??) axle housing, repair or replace?

 

[arrow]

I've stated before I am always amazed and gladdened by gentlemen such as yourself. I am glad you are taking advantage of an obvious ability gift. Most people looking at this tractor would give it a pass so hard the grass would rustle. It does bring to light about faith in companies. This appears to be a cost cutting measure tractor. It is an attitude one does not want to associate with a company with a history and legacy that runs to the very foundations of this country. All it takes is a few bean counters and pencil pushers to rip this institute right from its moorings and we are left with what? Can you trust this company again? If you owned this company and felt a connection to its vast history, would you want its name sullied with junk? Its really sad as it is a marker of our time. Where is pride in craftsmanship these days? We pray on altars with lesser priorities and the term "value" becomes bastardized with its new meaning. A meaning that is rammed down our throats as if it deserves credence. Gosh these pics pmo. That is why a guy such as yourself Mr. Krug is so valuable in today's world.

 

[mjncad]

All jokes aside, how are you going to address the aluminum (What was JD thinking??) axle housing, repair or replace?

Considering aluminum costs more than steel and weight savings on a tractor seems less important than on other vehicles; it seems odd that Deere would make the housings out of this metal.

 

[mjncad]

The hood armor is made by JD, but I can not find it in the parts book. There
are several "rental upgrade kits" that are not described, however. This
hood armor is awesome.....it must weigh at least 100 lb!

The new plastic is green all the way thru (ABS?) and not easily fixed when
broken. It replaced the earlier fiberglass hoods, which were aften smashed
but were easier to fix. I did a few on the 955s. The new plastics are
sourced from a plant in the US somewhere, according to the box the new
hood came it. I prefer sheet metal body parts, and I doubt the rental yard
will ever buy any tractor with plastic body panels again.

You'll find the hood armor parts on the JDparts web site under the 420, 430, & 460 loaders section.

The hoods and side panels are green all the way through while the fenders aren't. I believe they are all made of ABS; but I'm not sure.

 

[dfkrug]

Considering aluminum costs more than steel and weight savings on a tractor seems less important than on other vehicles; it seems odd that Deere would make the housings out of this metal.

I am dumbfounded by this design/manufacturing decision, too. It seems to
me that you need to bring a magnet with you when you get a tractor this
size. I would like to know what other tractors in this class (30+hp, 3000+
lb naked) use all-steel or part Al. Maybe other TBN members will post
about their CUTs. In terms of evolution, does the 4310 use Al? What about
JD's current crop, the 3xxx's?

As for fixing this, don't tell anyone, but I am going to take the axle housing
to a welder who does TIG process. Each housing new from Deere is $640.

As for analyzing this tractor, I see some mistakes like this that leave you
scratching your head (cuz it is likely cheaper to use cast iron/steel), and
some other areas where I am pleased with how they made certain parts
or subassemblies. (I just pulled apart the front wheel hub and it uses bigger
bearings and other parts vs. a similar sized Kubota I repaired a few years
ago.)

 

[dfkrug]

You'll find the hood armor parts on the JDparts web site under the 420, 430, & 460 loaders section.

The hoods and side panels are green all the way through while the fenders aren't. I believe they are all made of ABS; but I'm not sure.

That hood armor weighs over 100 pounds!

I think you are correct, the plastics are ABS. The rear fenders are very
thick, and neither of them are broken. I am scared to price THEM out.

 

[dfkrug]

Thx for the support, guys. I just got my engine block back from the
machine shop, so it looks like I can rebuild it with .25mm O/S pistons.

As for the FEL cylinders....the rods are only 25mm (one inch) in diameter.
Needless to say, most of the units have had theirs bent. The photo shows
one of the other 4300s in service....you can see the bucket cylinders are
rust colored. They have been rebuilt by a hyd shop that does not bother
to repaint. There are only one or 2 of these cyls that have NOT been
rebuilt (of 7 or 8 tractors).

 

[dfkrug]

Now for the dissassembly. Removing the FEL was tough. Without any
hydraulics, these things are terribly unwieldy. I ended up taking it all
apart to remove it. I like the QA loader bkt. I never had one of those.
The FEL pivots are in pretty good shape....at least all the pins are 25mm
in dameter.....the FEL pins on my 955s were quite a bit wimpier (17mm).

As I start removing things and splitting the tractor, I noticed that most
bolts are 13, 15, and 18mm head sizes. I have never SEEN an 18mm
socket, as none of my many socket sets comes with one. Very unusual.

 

[Scooby074]

18MM is one of those "Special" metric sizes. Its used alot on Japanese products especially. My honda has a 18MM sparkplug. It never comes in common sets for whatever reason.

 

[JohnDeere4300]

I'm glad to see you bringing a 4300 back to life.

Keep us posted & the pictures.