John Deere 4300 complete rebuild

[dfkrug]

Originally Posted by mjncad

My 4200 is a 2001 and has about 485 hours on it. As I recall the owner's manual says to get a valve adjustment every 500-hours. Mine runs just fine, and although I'm not fanatical about maintenance, especially washing my vehicles, I do try to stay on top of the mechanical stuff.

I would not worry too much about valve adjustment. This machine has
700-800hr on it and none of the 4300s at the rental place have had their
valves adjusted. If your engine starts to smoke or gets difficult to start,
that is a different story. If the valve lash increases, that should not be a
big worry as these are low-revving engines with low valve spring rates that
will minimize the peening effect (distortion) you can get with a loose
valve train. That is my opinion; hardcore engine builders may disagree.

I AM concerned about potential failure of the air hose. I warned the rental
yard about this problem and I think you should check it out, too. The drain
hose from the fuel filler catchment basin is pinched against the air hose and
I think you can reduce the risk of damage by removing this optional hose.
I hope other JD owners see this (incl 4x10 owners) and check it out.

[mjncad]

Originally Posted by dfkrug

I AM concerned about potential failure of the air hose. I warned the rental
yard about this problem and I think you should check it out, too. The drain
hose from the fuel filler catchment basin is pinched against the air hose and
I think you can reduce the risk of damage by removing this optional hose.
I hope other JD owners see this (incl 4x10 owners) and check it out.

Thanks for the tip on the air intake duct, I'll be sure to inspect mine even if I have to use a mirror or one of Rigid or Milwaukee's new reasonably priced snake-cams. Another excuse to buy a toy.

[Bruce-4310TX]

Il ck my 4310 this weekend, also any chance u could post a good pic of that hood protector i want one to save my new hood. Thanks

[dfkrug]

Originally Posted by Bruce-4310TX

Il ck my 4310 this weekend, also any chance u could post a good pic of that hood protector i want one to save my new hood. Thanks

I will do that, Bruce. I do not plan to use my JD hood armor. I happen to
have a 420 FEL brush guard that I am going to use.

Please check your rear axle castings to see if they are Al or steel and post
here. I am very interested in how many improvements JD has made when
they moved to your series in about 2002.

[dfkrug]

OK, now I am going to drain the hyd oil. I collected about 10 gallons, as
expected.

The first photo shows the main drain underneath the middle of the tractor.
it is connected to the suction pipe/hose that feeds the implement and
power steering pumps. Very accessible, but very vulnerable, too. Not
quite as vulnerable as my Kioti's imfamous low-hanging filter, but there
is no protection from rocks or logs! :-( Anyone break theirs?

The second photo shows my suction filter. It does not look good! It was
not that easy to remove because it was covered with metal fragments,
many more than can be seen here. Something broke inside there, no
doubt. It could not have been sucking very well due to all these pieces...
mostly non-ferrous, BTW. Don't forget to check your suction filter when
doing your 400hr oil replacement!

[dfkrug]

OK, now I am going to open up the range shift/final drive gearbox,
starting with the rockshaft cylinder housing.

After I got all the bolts out, I needed my forklift to get the housing off
the gearbox...it must weight 100lb or so. I plan to completely disassemble
the cyinder, rate-of-drop valve, and position control valve later. The first
thing to do after the top is off is remove the range shift shaft. The shaft is
easily broken off due to the weakness of an O-ring groove cut into it. Mine
is broken as expected. There is a TBN thread posted about this problem
and a well-documented repair....a quick search did not find it. Maybe
someone can post the link here and give credit to the poster?

The 2nd photo shows removing the shifter fork so the shaft can be pushed
out the side of the case. I am using a drift to pound out the roll pin while
I hold a magnet underneath. If the roll pin falls into the sump, it will be
hard to remove. The final photo shows the shaft coming out, and the now
removed shifter fork. The tire has to come off to get this shaft out.

[dfkrug]

Here I am removing the rear PTO cover. Nice big gears in there.

Oh my, look at the pieces of clutch friction disk in there! I picked
out enough fragments for more than one whole disk. There are probably
enough small fragment to fill a 2-oz cup. These are the fragments that
adhered to the suction filter above.

The PTO on this tractor is engaged mechanically and the rental yard has
had a bunch of them broken when the renter engages the clutch at
high RPM with a rotary mower attached. Sometimes the whole clutch
"basket" disintegrated.

[kennyd]

Originally Posted by dfkrug

The shaft is
easily broken off due to the weakness of an O-ring groove cut into it. Mine
is broken as expected. There is a TBN thread posted about this problem
and a well-documented repair....a quick search did not find it. Maybe
someone can post the link here and give credit to the poster?

HERE it is...

[dfkrug]

Oh, yes, it was Richard. Thx for tracking that down , Kenny. I bought
an OEM replacement shaft, mostly due to the concerns of needing a way to
seal the shaft against oil leaks. Poor design, no question.

[johndeere4300]

Originally Posted by dfkrug

OK, now I am going to drain the hyd oil. I collected about 10 gallons, as
expected.

The first photo shows the main drain underneath the middle of the tractor.
it is connected to the suction pipe/hose that feeds the implement and
power steering pumps. Very accessible, but very vulnerable, too. Not
quite as vulnerable as my Kioti's imfamous low-hanging filter, but there
is no protection from rocks or logs! :-( Anyone break theirs?

The second photo shows my suction filter. It does not look good! It was
not that easy to remove because it was covered with metal fragments,
many more than can be seen here. Something broke inside there, no
doubt. It could not have been sucking very well due to all these pieces...
mostly non-ferrous, BTW. Don't forget to check your suction filter when
doing your 400hr oil replacement!

I've learned a lot by following this thread.

That's a lot of metal fragments in the suction filter.... I have checked mine before and never found no metal.

I still need to check my air intake hose, and thanks for the warning on that!