John Deere 4300 complete rebuild

[Arkaybee]

Come on now. You've got us addicted to watching and learning from your mechanical genius and now it has been almost two weeks since you have updated your progress. We are starving for the latest "fix".

Arkaybee

 

[robin1]

HELP!! got a 4400 john deere that i use for my landscaping business.
crew had it on job site and it started losing power and got a little
knock in bottom end. want to get open to look and see. is there a way
to get oil pan off without splitting and to do rebuild on it, do you have
to pull engine or can you just clear everything in front of engine, i.e. the
radiator, battery, etc. please someone let me know... post or email me
at robinmayall@yahoo.com. thanks in advance........

 

[dfkrug]

....do you have
to pull engine or can you just clear everything in front of engine......

Welcome to TBN, ROBIN. Sorry to hear of your problem with your 4400.
As you may know, it is identical to the 4300.

In a word, no, you can not access the lower end on your engine without
removing it from the front subframe. The subframe which holds the front
axle and differential is mounted to the oil pan, which is a massive steel
casting. See photo. It is a big job.

(BTW, RKB, I am in the midst of assembly now and just got my front suframe
mounted to my rebuilt engine. Pix coming soon!)

 

[dfkrug]

OK, it has been a while since I posted. I am in the assembly process, mostly,
and I am juggling this project with others, including a new all-steel carport
structure (tractorport?).

So these posts are almost in real time. I revisited my FEL cylinders just a
couple days ago. Recall that I have at least one bent rod to deal with.
Remember the first photo below?

These JD cyls only have 25mm rods, so they are easy to bend. They also use
wire-retained cylinder glands. I guess both are cost-cutting measures. I
much prefer screw-in glands. This rod has apparently been replaced once
already.

In the 2nd photo, I show how to remove the gland. I do not recommend
using a pipe wrench unless you do not care about the marks it leaves in the
steel, or you have no other way to get a grip. Mine were already marked
up with pipe wrench marks, so a few more won't hurt. I also recommend that
you leave the cyl on the loader as a good way to hold it while you turn the
gland. If you look closely, you can see the wire retainer as it comes out of
the hole in the cylinder as I turn the gland.

If your cyls are off the loader, you need some way to keep them from turning.
Photos 3 and 4 show how I do that. This is how I hold the rod to remove
the piston nut, too. Since there are zerks on both sides of the cylinder, I
also needed to use a piece of wood with a hole to protect one zerk from
being damaged.

 

[dfkrug]

And here is my bent rod. It looks like I may be able to straighten it well
enough to be able to reuse it. I did have to pull hard with my tractor to
pull the rod and gland out. If you look closely at the aluminum piston, you
can see it is pretty scored up from all the side pressure it received from the
bent rod. Repairs will be posted soon.

 

[dfkrug]

And here is the rod, good as new. Well, almost anyway. I used my
hyd press, and I smoothed up a couple of small nicks with a diamond
file. I will reuse the seals.

 

[dfkrug]

However the manual calls for a valve adjustment at 500-hours. The engine sounds and works fine; but I think I'll read the shop manual in greater detail to see if this is something I can tackle myself.

I am putting my tractor back together in a somewhat different order than
the disassembly. One thing is the engine. If you remove the muffler and/or
the exhaust manifold, you may not have to remove the fuel tank to get
at the valve cover. See photo.

 

[F-I-T]

On the bucket and lift cylinders of my 420 loader, they include a little orange ring in the "kit" package that slides down the shaft and lays in the groove after you push the rod guide bushing back inside. Then you give it a yank, and it generally destroys the orange thingy, but it fills the gap while the expansion ring passes over it. FWIW.

 

[dfkrug]

On the bucket and lift cylinders of my 420 loader, they include a little orange ring in the "kit" package that slides down the shaft and lays in the groove after you push the rod guide bushing back inside. Then you give it a yank, and it generally destroys the orange thingy, but it fills the gap while the expansion ring passes over it.

Have you used the JD kit, FIT? That is good experience. My earlier JD
cyls used glands that were retained by inside snap rings and the JD kit
was over $40. Lots of "extras" in the kit, too. I don't buy the factory
kits anymore....I would rather order from a place like Hercules.

 

[mjncad]

I am putting my tractor back together in a somewhat different order than
the disassembly. One thing is the engine. If you remove the muffler and/or
the exhaust manifold, you may not have to remove the fuel tank to get
at the valve cover. See photo.

Thanks for the tip as removing the muffler looks a lot easier than getting the fuel tank out of there.