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Re: Case/Davis trencher backhoe
Posted: Wed Mar 15, 2023 12:17 pm
by MattA
Another option would be to use a pair of vice grips or pliers to hold the steel rod your pounding on. I've done it but on a much smaller scale than what your doing.
Re: Case/Davis trencher backhoe
Posted: Tue Mar 28, 2023 7:04 pm
by Eugen
The thumb pain is less annoying so I thought I relax a little trying to disassemble the cylinders. I was stomped a little by this inner locking ring that holds the gland in place. As is there was absolutely no way to get to it.
With help from
@Spike188 I figured the gland has to be pushed in far enough. Didn't go in easy, I used a copper hammer to whack the gland all around 'til it went in far enough to reach that ring. Tough ring too.
The rod came out then.
Re: Case/Davis trencher backhoe
Posted: Tue Mar 28, 2023 8:53 pm
by JSinMO
@Eugen Glad to hear your thumb is a little better, and your able to make some progress.
I’m enjoying the work you
@Spike188 and
@thebuildist are doing on your backhoes.
It’s making me want to bring mine back into the shop for a little sprucing up too! Hopefully I can work it into the rotation later this year.
Re: Case/Davis trencher backhoe
Posted: Wed Mar 29, 2023 6:31 am
by DavidBarkey
Anouther way to draw in that type of gland for removing the ring . Is to fill the top end with gear oil or the heaviest weight oil you have . Burp ALL air out and seal with appropriate cap . You only need a couple of inches of oil between the piston and gland . Stand upright and put more oil or grease on shaft and around gland to air seal . Cylinders small enough to pick up by hand , pick up and bang the bottom on an piece of hardwood . The enercia of the rod assembly when hitting the floor will draw the glad with it as the fluid creates a vacuum between the piston and gland. The larger ones use a hd ratchet strap looped around it and or a BFH and block of wood . Sorry guys about being late to the party , I don't always think of these things untill after people are done fighting with stuff .
Re: Case/Davis trencher backhoe
Posted: Wed Mar 29, 2023 7:25 am
by Eugen
Thanks Dave! It's a good procedure to remember for next time.

Re: Case/Davis trencher backhoe
Posted: Wed Mar 29, 2023 8:57 am
by thebuildist
Re: Case/Davis trencher backhoe
Posted: Wed Mar 29, 2023 12:35 pm
by Eugen

yep, nope
Wish I had a press of sorts for this task

Re: Case/Davis trencher backhoe
Posted: Thu Mar 30, 2023 8:45 pm
by Eugen
Cylinder 2 and 3 done taken apart, 2 was a bear, done over three days bit at a time, 3 was easy, done in about an hour.
Next I need to get the pistons and glands off, and start measurements to figure out which seals and o-rings to get.
After that tackle the swing cylinder(s).
Re: Case/Davis trencher backhoe
Posted: Thu Mar 30, 2023 9:25 pm
by JSinMO
@Eugen I have no doubt your still hurting, way to power through it!
Great job getting it apart. Looks like you’ll be reassembling pretty quick.

Re: Case/Davis trencher backhoe
Posted: Fri Mar 31, 2023 12:09 am
by Eugen
Doesn't hurt much anymore Jeff.
After the kids were asleep I managed to get the pistons off of two rods. The nut holding the piston takes a 1-11/16 socket, which I don't have. Luckily, after heating it up, it came undone real easy with the 30" pipe wrench.
Piston, gland, seals, and o-rings ready to go inside and get measured. But not tonight. Time for