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Case 644 lift and bucket cylinders overhaul

Posted: Mon Aug 28, 2023 4:28 pm
by Eugen
Hi guys, as far as I can tell by looking in all the parts manuals I could find for the 644 loader, the lift and bucket cylinders use the same kit seals, that is Case part numbers T41499 and C18574. If this is so, then all the seals I have measured and sourced for the other 644 should work on the current one. It'd be nice if someone who knows this for sure could confirm. :D

Of course, I could open up the cylinders again and measure everything, but I would like the loader to be functional until I get all the parts for the rebuild.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Mon Aug 28, 2023 8:18 pm
by Eugen
You know how things don't go exactly according to the plan? What started only as wanting to overhaul the lift cylinder quickly escalated to more. :109:


Big brother helps again.
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Engine goes out.
Engine goes out.
Some work needed in this area.
Some work needed in this area.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Mon Aug 28, 2023 8:36 pm
by Spike188
What's up now? Pump hose replacement?

Re: Case 644 lift and bucket cylinders overhaul

Posted: Mon Aug 28, 2023 10:12 pm
by JSinMO
Isn’t it nice having that big bucket to use as an overhead hoist?! :thumbsup:
Did you pull the engine to make room to work on the power steering?

Re: Case 644 lift and bucket cylinders overhaul

Posted: Mon Aug 28, 2023 10:47 pm
by Eugen
The real reason is to put in the engine I rebuilt a little while ago. I've been thinking of doing this for some time but now seemed like the right time. I'll pull out of loader valve too and rebuild it. Replace the inlet big hose, maybe the pump as well.

Wish I had a 14hp or 16hp diesel now. Unfortunately I only got a 10hp diesel, a 20hp diesel, and a 30hp diesel. 🤷‍♂️

Re: Case 644 lift and bucket cylinders overhaul

Posted: Tue Aug 29, 2023 8:29 am
by Spike188
@Eugen I admire your ambitious fortitude when implementing a repair job. I told a friend that lazy runs deep in my veins. They didn't believe it but they don't see the projects at home that never get finished, that started out as good dreams.

My 8th grade ag teacher said, "excuses are like butt holes. If you don't have one you are going to be in a world of hurt."

Maybe "The cobblers kids never have shoes." applies to me, but the dreams of finishing a 646lbh and a 4118AH live on.

Todays words of self proclaimed wisdom as numbing agent takes effect before the dentist starts grinding.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Tue Aug 29, 2023 9:53 am
by Eugen
@Spike188 there's nothing like a ramble from the dentist chair waiting for the anesthetic to kick in. :43:
But don't be so hard on yourself. I know for a fact that you repaired more devices in your life than I have seen in movies, and you're still doing that for a living. I also know that one is not the most eager to do the same type of thing at home as he does all day in his day job. When my wife asks me to do some job on the computer for her I do it, but it's something I avoid completely, after doing this for years as my day job. Plus I know that you'd finish the 646lbh and the 4118AH if you really needed them. :thumbsup:

There's a little more to the story of this 644. Because it was the functional one from the beginning, it got little attention. The benefit of the yellow 644 was that it came as parts, so it was an easy decision to overhaul things as building went on. Which was why I wanted to keep the yellow one, to avoid doing another overhaul which I knew this red one would need one day. See, I'm lazy for that. :wave2:

One thing I forgot to mention about this 644: the exhaust was done so by the PO that a proper fix needed the engine pulled out. I tried to fix/patch it a few times but it was still leaking exhaust fumes right under my nose. The smell of exhaust bothers me greatly! :106:

There, my ramble for today :wave3:

Re: Case 644 lift and bucket cylinders overhaul

Posted: Tue Aug 29, 2023 5:18 pm
by Eugen
The gunked up dirt and hardened oil this valve had on was next level. Took some rubbing in diesel to get it off. Preparing for disassembly.

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Re: Case 644 lift and bucket cylinders overhaul

Posted: Tue Aug 29, 2023 10:19 pm
by Eugen
Valve came apart easily.
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There are two o-rings for each spool. The spool for the bucket tilt has the o-rings on the spool itself, one top one bottom, sae size -111 with 7/16 ID and 3/32 CS. The srm lift spool has top and bottom o-rings on the inner body of the valve, sae size -114 with 5/8 ID and 3/32 CS.

The spools were pretty dull on all contact surface. So I put them in the lathe and shined them with 600 grit paper.

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The arms lift spool had noticeable tiny pitting near the top, so it got a little more polishing treatment.
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Used this contraption, 600 grit paper rolled thick and taped on a steel pin, to polish the inner surface of the valve body top and bottom for the spool that has the o-rings on the spool.

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Re: Case 644 lift and bucket cylinders overhaul

Posted: Thu Aug 31, 2023 1:24 pm
by Eugen
Polished, oiled, with new o-rings, buttoned up and ready to go back in.

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All the seals came in today so the lift and bucket cylinders are waiting patiently their turn for rebuild. It's not going to happen today though.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Thu Aug 31, 2023 4:54 pm
by Spike188
@Eugen
cylinder teardown.jpg
This is the method I used for breaking the nut loose on this shaft. The clevis end is clamped in the vise. An open end wrench with a cheater pipe extension slipped over it and drawn down on.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Thu Aug 31, 2023 6:33 pm
by Eugen
Thank you Eugene! I admit not using wrenches as much as sockets. I don't know why, a habit perhaps. If there's enough clearance I always reach out to sockets and ratchet or beaker bar. 🤷‍♂️

Re: Case 644 lift and bucket cylinders overhaul

Posted: Fri Sep 01, 2023 5:28 pm
by Eugen
Back to garden tractors.

The rod's out.

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Re: Case 644 lift and bucket cylinders overhaul

Posted: Fri Sep 01, 2023 5:45 pm
by Eugen
Gland and piston size difference.

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Btw the seals were in really bad shape.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Fri Sep 01, 2023 7:54 pm
by Eugen
The main rod seal inside the gland was originally an o-ring plus backup ring. I chose to replace that with a u seal of appropriate size.
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It provides a superior seal and lasts longer. A bit tricky to install without that special tool, but it can be done. This is what it looks like inside the gland.

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The cylinder is assembled once again, with plenty of HD grease around the retaining rings of the gland.

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Re: Case 644 lift and bucket cylinders overhaul

Posted: Sat Sep 02, 2023 1:31 pm
by Eugen
Re-installing the loader valve involves quite a bit of fiddling. No matter what I do there's oil spill. :109:

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This tractor needs an engine.

Re: Case 644 lift and bucket cylinders overhaul

Posted: Sat Sep 02, 2023 7:09 pm
by Eugen
With no functional loader I had to wrestle the engine in after using a jack to lift it.
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Only hooked up the pump bracket and called it a day. Some simple tasks take a long time.