Bent bucket cyl on model 48 backhoe

[DanMc77]

I hate it when this happens.

I was digging out some stubborn roots and rocks, when my bucket would no longer curl. I got off and found this. WTF!!!!!!

JD dealer wants a thrifty $1500 for that cylinder, and they don't even have one available. They stock a replacement rod for $500. They said they don't have any specs for the cylinder. So they're pretty much useless.

I just replaced one of the stabilizer cylinders from Magister Hydraulics for $170. (some modifications required). So it looks like I'll have to go the same way with this one. Anybody have specs for that bucket cylinder?

 

[jthibodeau89]

You may want to consider going up in rod diameter on the replacement cylinder. This will only affect the dump force/speed.

 

[jpolcyn]

how in the world that can even happen is unbelievable to me. but bang up job on getting her done!

 

[CH4Ohio]

Take it to a hydraulic repair shop. They'll have some options for you. I'd think the worst that could happen is they replace the shaft and use your bushing end and new seals.

 

[daman1]

I've seen that before on sub-compacts I bet you there's a manufacturer defect in the iron in that rod it was forged too soft.

Happen to have any warranty left on it?

 

[DanMc77]

What was I doing? Nothing I haven't done 50 times before. I had the boom and dipper fully extended. I pushed the teeth down into some roots and lifted the boom and pulled the dipper together. Lots of pull this way.

I would think that a hydraulic cylinder rod should be super stiff and unable to bend like this. Whoever made this for JD stiffed them - AND ME!

Increasing the rod diameter is definitely something I'll work on, if I can find it.

 

[DanMc77]

I found a new cylinder for the backhoe, for $177. That's just a little less than JD's $1500 for a cylinder that is probably defective.

2.5 in bore x 18.25 in stroke Loader Welded Hydraulic Cylinder | Magister Hydraulics

2.5 in bore x 18.25 in stroke loader double acting welded hydraulic cylinder with cross tube ends. Made for heavy-duty hydraulic equipment. It can be used for a variety of automotive hydraulic applications, construction equipment, agricultural machinery, forestry and logging, and mining...

www.magisterhyd.com

This is a "loader cylinder" that has the correct stroke, but an extra 8" of rod when it's retracted. I'll need to have the rod shortened and the rod cross-tube welded back on to get the final proper dimensions. This one is also a 1 1/2" dia rod versus the 1 1/4" rod on the original. JD has a 1 1/2" dia pin bore on the body end, but this one has 1 1/4" bore pin, so I'll have to use a 1 1/4" pin and make some shims on the lathe for that end.

Alternatively, this one could be used without cutting and welding the rod, but it has 1/2" less stroke than the original, and it only has 1" pins. I have a good friend that can easily cut the rod and weld the cross tube back on, so that's no issue. I don't want to lose stroke.

Your thoughts on this? I'll wait a day before ordering, hopefully those more experienced can share some insights.

2.5 bore x 18 stroke hydraulic cylinder, welded cross tube double acting cylinder | Magister Hydraulics

2.5" bore x 18" stroke cross tube hydraulic cylinder 3500 PSI. Heavy-duty hydraulics, 2-year warranty, free ground Continental US shipping. Magister cylinders manufactured using steel piston and steel threaded gland with wear rings for long life. Welded cross tube ends, honed cold-drawn tubing...

www.magisterhyd.com

Not too bad, but it's sad that the backhoe is disabled for a few weeks.

 

[jthibodeau89]

I would not consider dropping the pin size to 1".

Looking at the first cylinder, i would be concerned with opening up the hole in the base end to 1.5". Do you know the closed length of the trashed cylinder? When shortening the rod, you could cut off the existing cross tube and have a new 1.5" ID x 2.5" OD DOM tube welded on to the base. Are the hydraulic outlets in the correct orientation? The cylinders on my 430 loader have an extended length from the hydraulic fitting to the base hole. Fittings are also aligned with the base pin axis instead of perpendicular.

This reminds me that i need to replace the curl cylinders on my 430 loader. One side is leaking at the gland due to nicks on the rod. I'll check the magister catalog for what i need.

 

[DanMc77]

If I use the first one, the loader cylinder, that has 1 1/4" pins. Couldn't I use a 1 1/4" pin, then machine bushings to fit into the 1 1/2" bores in the dipper?

I've been happy with Magister. Mostly, I like their selection, and the prices are great too.

 

[jthibodeau89]

Yes, you could bush the mounting ears down to 1 1/4". Will you also be making an alloy 1 1/4" pin? Does the width of the base tube match the mount on the BH?

What I was asking is if the hydraulic fitings on the replacement cylinder are oriented correctly. If not, it is easy to reorient by removing the current 1 1/4" tube and replace with a 1 1/2" tube in the correct orientation and width.

In my case the cylinder base mount is a tang type, with a 5" longer retracted and extended lengths for the 18" stroke. I cannot find an exact fit cylinder, and will have to modify the cylinder base mount.

 

[LD1]

In the first post you asked if anyone had specs for the cylinder on that backhoe but you have failed to give a model of the hoe?

Regarding a cylinder.....There should be nothing wrong with your current cross tubes. They are the right pin diameter and right width and no clearance issues. So simply shop for a cylinder that has the right bore, stroke, and rod diameter. Dont worry about what ends it has.....clevis, swivel eye, cross tube, etc. Sometimes one is cheaper than the other. Simply cut them off and disregard whatever comes on the cylinder that fits your specs. Then cut YOUR cross tubes off and weld on the new cylinder. Dont get much simpler than that.

 

[beenthere]

LD1, more than one model 48?

 

[DanMc77]

I chose this cylinder in part because the hydraulic fittings are oriented properly. I want to keep the modifications to the cylinder at a minimum, so bushings are preferable to me rather rather than replacing the base mount. I have some 1 1/4” 4140 TGP left over from pins I made for the thumb. I can use that. I may have to machine down the base pin tube if they’re too wide. I’ll use the pin tube off the original cylinder to weld onto the new one.
This is funny. I just finished replacing one of the stabilizer cylinders because I got sloppy and let a rock drop on the chrome rod. Then the next day this happens and I’m back replacing another one.

 

[bindian]

I bent a stabilizer cylinder rod on my Bradco 511. Mahindra didn't have a new rod available. But Houston Hydraulics rebuilt my rod, including welding the old mount on the rod for $200. I replace all my own seals.
hugs, Brandi

 

[LD1]

I chose this cylinder in part because the hydraulic fittings are oriented properly. I want to keep the modifications to the cylinder at a minimum, so bushings are preferable to me rather rather than replacing the base mount. I have some 1 1/4” 4140 TGP left over from pins I made for the thumb. I can use that. I may have to machine down the base pin tube if they’re too wide. I’ll use the pin tube off the original cylinder to weld onto the new one.
This is funny. I just finished replacing one of the stabilizer cylinders because I got sloppy and let a rock drop on the chrome rod. Then the next day this happens and I’m back replacing another one.

Going with bushings means you are downsizing the pins. That could very well be the next weakest link

 

[DanMc77]

Going with bushings means you are downsizing the pins. That could very well be the next weakest link

Agreed. But if Magister sells this cylinder with 1 1/4” pin tubes, that gives me some confidence that a 1 1/4” is ok. After all, the original cylinder has 1 1/4” on the rod end. It seems a bit goofy that JD would have different size pins on the same cylinder: 1 1/4” on the rod end, and 1 1/2” on the base end.

 

[ptsg]

I say you will be fine with 1 1/4" pins and bushings to make it fit the 1 1/2". If it ends up breaking, although unlikely, you can always modify the eye on the cylinder and make it work with the bigger pin.

On my homemade backhoe, I used 24 mm (~15/16") and 20 mm (~25/32") pins, which are actually made out of 10.9 grade metric bolts with just the threaded section cut off. I have yet to break a pin and that thing is used and abused beyond it was designed for, but that was exactly why I built a backhoe from scratch, so I would be afraid of breaking the tractor, had I made a 3 pt one.

Pics for reference:

 

[DanMc77]

PT: very cool backhoe. That’s pretty amazing work. I think stabilizers would make it even more amazing.

 

[ptsg]

PT: very cool backhoe. That’s pretty amazing work. I think stabilizers would make it even more amazing.

Thanks! Yes, it had stabilizers, although I had to manually apply those by lifting the machine, move the stabilizers down and put the pin on. This was not very practical, specially digging trenches, so I never really use the stabilizers much.

The machine handles alright without the stabilizers. Only tip it will lift the front, since it has a pivot point in the middle of the 2 rear axles, is when I'm digging stumps or rocks, or lifting something heavy. In those cases, I just put two blocks of wood between the subframe and the main chassis to prevent it from pivoting.

I think a rear blade would be more usefull and that's future plans for the machine.

 

[DanMc77]

Thanks! Yes, it had stabilizers, although I had to manually apply those by lifting the machine, move the stabilizers down and put the pin on. This was not very practical, specially digging trenches, so I never really use the stabilizers much.

The machine handles alright without the stabilizers. Only tip it will lift the front, since it has a pivot point in the middle of the 2 rear axles, is when I'm digging stumps or rocks, or lifting something heavy. In those cases, I just put two blocks of wood between the subframe and the main chassis to prevent it from pivoting.

I think a rear blade would be more usefull and that's future plans for the machine.

The mini excavators don’t have stabilizers, but have a blade that can serve the same purpose, so your comment makes a lot is sense. I think maybe their tracks are wide and stiff enough to handle the load.

Looks like you dug up a dinosaur turd.