John Deere 4300 complete rebuild

[mjncad]

I got around to checking mine out today using an inspection mirror and a flashlight. From what I can see, the intake hose is barely touching the fuel tank; but the fuel overflow hoses are not trapped between the intake hose and the tank. I didn't see any obvious evidence of wear on the hose.

That is definitely one cramped installation. I thought about seeing if there was room above the battery for the air cleaner, and it would be tight; but I'm concerned it would negatively affect cooling air to the radiator and oil cooler.

Moving the air cleaner out from under the hood to a high location may be possible; but the intake hose would have to go through the side panel in some manner, and that would make removing the panel difficult.

I think it would be interesting to try and run a Milwaukee or Rigid flexible camera inspection tool down the hose through the air cleaner and check it that way. The trouble is I don't have one...yet.

Bottom line is this is one thing for 4200 - 4400 owners to keep an eye on.

 

[dfkrug]

The last picture shows clearnace between both hoses, but not much! If the gas tank moves or is somehow pushed down, it will make contact. There was no/no contact or even appearance of wear on my manifold air intake hose.

That's good news, Wayne. You can see in your last 2 pix that the overflow
hose is quite warn, due to being pinched, plus the vibration, plus the grit.
That's what will happen to any hose that gets pinched in there.

Getting a good view in there may also be aided by removal of the muffler,
which is quite easy.

 

[JohnDeere4300]

That's good news, Wayne. You can see in your last 2 pix that the overflow
hose is quite warn, due to being pinched, plus the vibration, plus the grit.
That's what will happen to any hose that gets pinched in there.

Getting a good view in there may also be aided by removal of the muffler,
which is quite easy.

I had to go back and look at Wayne's pictures of the 'overflow hose' and it does look worn.

JD should have done a better job routing these hoses.

 

[Wayne_H]

Yea, I think the pictures may be a bit deceptive, the overflow is not worn at all. My overflow does not touch the air intake, I think what you may see is where some of the dirt is off ot it. My bad for not cleaning it better! Which I will do now.

Wayne

 

[dfkrug]

OK, now I am going to take a bit of a detour. The engine is mostly
together, but I decided not to use the water pump and I changed my mind
and will go with an all-new filter housing. So the WP, etc will be ordered
with my next batch of parts.

While I waited for my pistons, I decided to rebuild my right front MFWD
axle hub. It leaked like a sieve, and I have just completed the refurbishment.
It took a long time because it was tough, and I had to make a special tool,
and order new parts.

The first photo is the front subframe. You can see the frame rails that bolt
to the engine's oil sump. This is the earlier of the two main types of axles
that came with the 4x00 tractors. It uses a single two-sided power
steering cylinder connected to articulated tie rod ends on each side. Later
units made use of a single-sided cyl with a long tie rod to attach to the
other hub. I do not know what the complaint was about these earlier
units....mine looks fine and there is no bent tie rod to deal with. (This is
the only rental tractor I have owned that did NOT have a bent tie rod.)

The front axle pivot is a very substantial unit with no wobble and no leaks.
I might not even take it apart!

The 2nd photo is the axle ID. The model number (next to the date) was
completely obscured by paint....you must have this number to get parts
for the hubs. There are 4 or 5 diffferent hubs.

3rd photo shows draining the axle. This one is full of tractor-hyd fluid, it
looks like. (Not straight hyd fluid as I stated earlier.) I plan to go to
80/90 gear oil when finished. I am a bit surprised that there is some
corrosion in there, even in places fully submerged in fluid. JD uses a
hex socket head drain plug. This is a bad idea since this area is completely
unprotected from rocks. The left side plug is damaged and some surgery
will be required to remove it. (This tractor has fought me again and again.)

Finally, I removed the tie rod end. This one is huge....bigger than my only
pickle fork, so I resorted to a hammer (with protection), and it came right
out.

Next, I start the disassembly. Warning: replacing the seals on this hub
is not for the novice! There are difficult large snap rings, and one special
tool is required.

 

[mjncad]

Geez, that almost looks like ATF coming out of that hub. JD specs out the same hydraulic oil for the front axle as the main system.

You should be able to find cast into the housing 'SPICER' who made the MFWD axles for our series of tractors.

For what it's worth, I use JD's regular viscosity hydraulic oil since most of my usage is in hot weather.

 

[kebo]

Geez, that almost looks like ATF coming out of that hub. JD specs out the same hydraulic oil for the front axle as the main system.

You should be able to find cast into the housing 'SPICER' who made the MFWD axles for our series of tractors.

For what it's worth, I use JD's regular viscosity hydraulic oil since most of my usage is in hot weather.

Two weeks ago I changed the hyd/tranny fluid in my JD 790 with 400hrs on it. It all came out looking red just like ATF fluid!! I am the third owner of this tractor so I can't say what the two previous owners did (if anything) with regards to changing the hyd/tranny fluid. Honestly, I have my doubts that either one of them changed the fluid but I can't say for sure. What I thought was interesting was that JD recommends their low viscosity hyd/trans fluid that I put back in, but it looks more like weak Karo syrup, not red like what came out of mine?? So maybe it was changed sometime in the past.

 

[kebo]

Geez, that almost looks like ATF coming out of that hub. JD specs out the same hydraulic oil for the front axle as the main system.

You should be able to find cast into the housing 'SPICER' who made the MFWD axles for our series of tractors.

For what it's worth, I use JD's regular viscosity hydraulic oil since most of my usage is in hot weather.

Two weeks ago I changed the hyd/tranny fluid in my JD 790 with 400hrs on it. It all came out looking red just like ATF fluid!! I am the third owner of this tractor so I can't say what the two previous owners did (if anything) with regards to changing the hyd/tranny fluid. Honestly, I have my doubts that either one of them changed the fluid but I can't say for sure. What I thought was interesting was that JD recommends their low viscosity Hygard fluid that I put back in, but it looks more like weak Karo syrup, not red like what came out of mine?? So maybe it was changed sometime in the past.

I'm in SC where it doesn't get real cold so I used three gal's of the low viscosity Hygard, and one gallon of the regular viscosity Hygard. I don't guess it will hurt anything to mix it???

 

[dfkrug]

Geez, that almost looks like ATF coming out of that hub.

Yeah, it is pretty reddish. Most of what I use is also red-brown colored:
Chevron 1000 THF, and Kubota UDT.

I wonder if the oil in this axle has ever been changed.....

 

[dfkrug]

OK, now it is time to pull the hub off and take it apart. After taking
off all the bolts, I broke the glue seal and it came right off.

The first snap ring was easy....the set of snap ring pliers I used is shown.
It holds on a straight roller bearing, made by LinkBelt in the US. I have not
run into that brand or type of bearing before. Very heavy-duty, IMO.
Other hubs I have seen use ball bearings here.

The third photo shows the hub fully disassembled. I needed my shop
press to get it apart. After I replaced the seal, I used the press again
to get it back together...it took some serious pressure, too. Nice big
hub shaft, and all bearings were in good shape.