John Deere 4300 complete rebuild

[dfkrug]

Once I got the loader off, I went thru a second session with the pressure
washer. I cleaned off buckets of dirt, while removing the few remaining
body panels, seat, floor boards, radiator, etc. (And that 100 lb nose
protector.)

And here is my "eureka moment". The report on this tractor was that it
ran, but very poorly, with lots of black smoke. The air filters were correct
and in place, so the cause of the engine failure was unknown. Until now.
The first photo shows a split in the air hose between the air filter housing
and the air intake mainifold. The culprit hose, which is open to dirt, is
pinched between the fuel tank and the valve cover. The split was invisible
until I cleaned things up and started to remove the bracket that holds the
filter housing.

Now I need to get the fuel tank out to get access to the valve cover and
the air intake manifold. I have never seen such a difficult to remove tank!
I had to remove the steering system support, PS hard lines, instrument
cluster, fuse panel, numerous brackets, and the 2-sided brake pedals. The
pedals pivot on a shaft that goes through the middle of the the fuel tank!
JD was willing to do ANYTHING to get 10 gallons of fuel in there it seems.
I give deere a LOT of credit for putting a fuel drain in the tank. Every CUT
I have rebuilt has had sludge in the bottom of the tank, and this is the first
time I have had a drain petcock. The jar shows the last bits of liquid I
removed thru the drain. I had to blow into the drain a few times to get
the last to come out.

[dfkrug]

At last I got the fuel tank out....it took hours! There is NO access to
the engine while the tank is in, which means no valve adjustment and,
in my case, no access to the engine ID. (There are 2 different engines
used in the 4300, and I needed to know which one I had inorder to buy the
correct pistons.) Hmmmmm.

So here is the damaged hose. It was pinched between the tank and the
valve cover, and an additional hose. Vibration, dirt, and a non-reinforced
hose did this poor machine in. It seems to me that a fiber-reinforced hose
(like a water hose) could have been used to avoid this problem.

Look inside the air intake.....yeeecchh! What you see is the air heating
element (used instead of glow plugs) covered with dirt. Now I am in a
hurry to get that engine open because I am sure some water got in there
with all the pressure washing that I did.

[mjncad]

Good grief, I always wondered how deere got 10-gallons of fuel into that small volume; now I see how they did it with every nook and cranny filled with fuel. Isn't blow-molding a wonderful thing?

I have the Deere shop manual; but I've never read how to get the valve cover off to do a valve adjustment, and mine is coming up on the 500-hour mark for that maintenance service. I'm dreading to find out how much the dealer will charge me for that chore.

[JohnDeere4300]

Good grief, I always wondered how deere got 10-gallons of fuel into that small volume; now I see how they did it with every nook and cranny filled with fuel. Isn't blow-molding a wonderful thing?

I have the Deere shop manual; but I've never read how to get the valve cover off to do a valve adjustment, and mine is coming up on the 500-hour mark for that maintenance service. I'm dreading to find out how much the dealer will charge me for that chore.

Can you imagine what it would have looked like if Deere went with a 12 or 15-gallon.

Yea blow-molding is so wonderful.

mjncad,
(What year is yours ?)

(Is your tractor acting in a way that it needs a valve adjustment ?)


My tractor is a 01-model with over 800-hours.... The service that i have done is all fluid, oil, filters, cleaned the suction screen, checked all hoses and other maintenance.

I haven't ever done the "valve adjustment" and my tractor runs as good as the day they delivered it, and i really don't know how a 4300 would act to need this part of the service done

mjncad or dfkrug,

Should i be getting the "valve adjustment" done with the hours i have on it ??

I don't have the shop manual but i need to get one.

[JohnDeere4300]

Once I got the loader off, I went thru a second session with the pressure
washer. I cleaned off buckets of dirt, while removing the few remaining
body panels, seat, floor boards, radiator, etc. (And that 100 lb nose
protector.)

And here is my "eureka moment". The report on this tractor was that it
ran, but very poorly, with lots of black smoke. The air filters were correct
and in place, so the cause of the engine failure was unknown. Until now.
The first photo shows a split in the air hose between the air filter housing
and the air intake mainifold. The culprit hose, which is open to dirt, is
pinched between the fuel tank and the valve cover. The split was invisible
until I cleaned things up and started to remove the bracket that holds the
filter housing.

Now I need to get the fuel tank out to get access to the valve cover and
the air intake manifold. I have never seen such a difficult to remove tank!
I had to remove the steering system support, PS hard lines, instrument
cluster, fuse panel, numerous brackets, and the 2-sided brake pedals. The
pedals pivot on a shaft that goes through the middle of the the fuel tank!
JD was willing to do ANYTHING to get 10 gallons of fuel in there it seems.
I give deere a LOT of credit for putting a fuel drain in the tank. Every CUT
I have rebuilt has had sludge in the bottom of the tank, and this is the first
time I have had a drain petcock. The jar shows the last bits of liquid I
removed thru the drain. I had to blow into the drain a few times to get
the last to come out.

I have been following your work on this & trying to learn from it, but after reading what you have to take off just to get to the valve cover, i starting to fill a little ill.... The picture with the sludge in the jar really looks bad.

What made it smoke a lot with black smoke ??

From the sound of it you have done a lot of rebuilds, but this is the first one I've seen you do.... After you complete the rebuilds, do you sell them or keep them around for your use ??

You should have bought the "broken in half 4300s"

I really liked the 100 lb. nose protector, and really that's the first time I've seen one.

Thanks for sharing your work!

[dfkrug]

Should i be getting the "valve adjustment" done with the hours i have on it ??

Valve adjustment? Well the maintenance schedule prob does call for them....
I do not know the frequency. If an engine goes a REALLY long time without
adjustment, eventually you can get valves that do not fully close, so you
get a loss of compression, resulting in hard starting, and maybe even burnt
exhaust valves. Or the lash gets greater, which is not as big of a concern. On a gas engine, you can hear excessive lash (tick, tick, tick), but it is hard
to hear on a Diesel.

The bigger concern for you guys with a JD 4200/4300/4400, and maybe the
4x10s is that you could be in for a split air hose. This event will cause
the engine to eat dust, eroding your cylinders, with quick failure. As the
engine starts to get lower and lower compression, it will be harder to start
and you will get more black smoke, due to partially burned fuel. Checking
your hose can only be done if you remove the fuel tank.

BTW, draining your fuel and rinsing out the sludge is not hard at all, so you
may want to do this bit of preventive maintenance.

[WilliamBos]

Thanks for sharing, and letting us experience this with you. I look forward to following along as you progress.

[dfkrug]

From the sound of it you have done a lot of rebuilds, but this is the first one I've seen you do.... After you complete the rebuilds, do you sell them or keep them around for your use ??

You should have bought the "broken in half 4300s"

The B21 was the first tractor that I fully documented, but I have done
numerous cars, trucks, m/cs, and tractors. I used the B21 for several
months before selling it. I like to fully test the finished rebuilds, as well
as use them with implements not currently on my main tractor. I don't
like changing implements if I do not have to. So the JD I will use for a
while, then put out the word to my network that I have a machine for sale.
If that does not sell it, I will list the machine on Craigs or eBay. (I still
want a broken NewHolland w/HST, BTW.)

When I posted the thread about the 2 broken machines on eBay, I was
stunned, as I had just ordered $2500 in JD parts. Too late to buy those
machines, though I would have jumped at them earlier!

[JohnDeere4300]

Valve adjustment? Well the maintenance schedule prob does call for them....
I do not know the frequency. If an engine goes a REALLY long time without
adjustment, eventually you can get valves that do not fully close, so you
get a loss of compression, resulting in hard starting, and maybe even burnt
exhaust valves. Or the lash gets greater, which is not as big of a concern. On a gas engine, you can hear excessive lash (tick, tick, tick), but it is hard
to hear on a Diesel.

The bigger concern for you guys with a JD 4200/4300/4400, and maybe the
4x10s is that you could be in for a split air hose. This event will cause
the engine to eat dust, eroding your cylinders, with quick failure. As the
engine starts to get lower and lower compression, it will be harder to start
and you will get more black smoke, due to partially burned fuel. Checking
your hose can only be done if you remove the fuel tank.

BTW, draining your fuel and rinsing out the sludge is not hard at all, so you
may want to do this bit of preventive maintenance.

Thanks for all the info!

I will have to do some checking on that.

[mjncad]

Can you imagine what it would have looked like if deere went with a 12 or 15-gallon.

Yea blow-molding is so wonderful.

mjncad,
(What year is yours ?)

(Is your tractor acting in a way that it needs a valve adjustment ?)


My tractor is a 01-model with over 800-hours.... The service that i have done is all fluid, oil, filters, cleaned the suction screen, checked all hoses and other maintenance.

I haven't ever done the "valve adjustment" and my tractor runs as good as the day they delivered it, and i really don't know how a 4300 would act to need this part of the service done

mjncad or dfkrug,

Should i be getting the "valve adjustment" done with the hours i have on it ??

I don't have the shop manual but i need to get one.

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. Like you I've done fluids, filters and grease on a regular basis; but knock on wood that's it.

Since I added the front posts for my canopy and there are wires running through them, removing the fuel tank could become even more of a hassle than normal.

I would have accepted a gallon or two less fuel capacity in exchange for less hassle to get the valve cover off. Although most of us don't put 500-hours on our CUT's very quickly, there are places like rental yards that do, and taking a machine out of service for a few days to do a routine maintenance chore seems silly.

I'm using a few days as a guess depending on a dealer's service backlog, or a DIY'ers skill at working on their machines.