Repacking Cylinders

[wng-2]

Good afternoon, I have a Kubota L 4400 Hydro, with an LA 703 loader. This morning my bucket started failing to stay curled. I am thinking the cylinders need repacked? I was wondering if you guys could tell me what I need to buy, and a good source? Thanks very much.

 

[TheOldHokie]

Seal kit - p/n 7J291-64400 - 2 reqd.

Looks like they are about $150 each. Might want to think about new cylinders at that price.

Dan

 

[wng-2]

Seal kit - p/n 7J267-63402 - 2 reqd

Dan

Thanks!

 

[Henro]

Seal kit - p/n 7J291-64400 - 2 reqd.

Looks like they are about $150 each. Might want to think about new cylinders at that price.

Dan

New kubota cylinders for the curl on my LA402 loader were $600 each, while a rebuild by a hydraulic shop was $100 each...

Just a data point.

I would probably take those cylinders to a hydraulic shop if I were the OP. Looking at the parts diagram for my cylinders I was amazed at how many seals/O-rings were used in them.

 

[TheOldHokie]

New kubota cylinders for the curl on my LA402 loader were $600 each, while a rebuild by a hydraulic shop was $100 each...

Just a data point.

I would probably take those cylinders to a hydraulic shop if I were the OP. Looking at the parts diagram for my cylinders I was amazed at how many seals/O-rings were used in them.

I was not suggesting he buy Kubota cylinders. $150 per cylinder will go a long way in the aftermarket. Looking at the parts diagram for his loader the OEM cylinders are pretty simple.

Dan

 

[Henro]

I was not suggesting he buy Kubota cylinders. $150 per cylinder will go a long way in the aftermarket. Looking at the parts diagram for his loader the OEM cylinders are pretty simple.

Dan

Might be simple to find exact after market cylinders for someone with know how/experience.

For me not so simple. I took the easy way out and have been totally satisfied with the rebuilt cylinders...probably at less dollars than after market ones would have cost, if I could have found them, after spending hours or maybe days (as an unexperienced amateur at this) trying to find an exact replacement...

 

[TheOldHokie]

Might be simple to find exact after market cylinders for someone with know how/experience.

For me not so simple. I took the easy way out and have been totally satisfied with the rebuilt cylinders...probably at less dollars than after market ones would have cost, if I could have found them, after spending hours or maybe days (as an unexperienced amateur at this) trying to find an exact replacement...

If you got them rebuilt for under $300 you did fine. But not much know-how required to find new ones - lots of manufacturers providing cylinders for small loaders. Bore and stroke are in the owners manual - LA703 is 1.9 x 18.9. You just need to make sure the ends will fit the mounts on the bucket and arms. and the retracted length is close - here a couple real close matches that will likely drop right in on an LA703. Took me longer to find the bore and stroke for the loader than it took to find the cylinders:

Wol;verine Welded Loader Cylinder

Chief Welded Loader Cylinder

Dan

 

[Henro]

… - here a couple real close matches that will likely drop right in on an LA703. Took me longer to find the bore and stroke for the loader than it took to find the cylinders:

Wol;verine Welded Loader Cylinder

Chief Welded Loader Cylinder

Dan

They may be a good replacemen, do not know. But we have an expression locally “Close only counts in horse shoes”.

Understand the need to make sure everything is compatible.

In my case, now and in the future I will again first try a local hydraulic shop for a rebuild, and use the aftermarket replacement Avenue if rebuild is not possible for some reason. KISS approach I suppose…

 

[wng-2]

I bought this kit. I hope it will be ok. I will decide when it arrives if I want to do it myself, or ask somebody to do it..
All States Hydraulic Seal Kit Compatible with Kubota 7J291-64400

 

[Dusty Dan]

Could the problem be the control valve rather than the cylinder?

 

[wng-2]

Could the problem be the control valve rather than the cylinder?

The seals definitely need changed, and should arrive tomorrow. I think the rods might have a slight bend though. I may just bring the whole thing to a local tractor guy....

 

[D2Cat]

A slight bend should not be a detriment to the function of the cylinder. If the seals are the correct parts they should work fine.

I've had cylinder rams bent enough I took them to a machine shop and had them straighten them. They put it in a press with brass to protect the ram. Came out fine!

 

[wng-2]

I was not suggesting he buy Kubota cylinders. $150 per cylinder will go a long way in the aftermarket. Looking at the parts diagram for his loader the OEM cylinders are pretty simple.

D

I've had cylinder rams bent enough I took them to a machine shop and had them straighten them. They put it in a press with brass to protect the ram. Came out fine!

A slight bend should not be a detriment to the function of the cylinder. If the seals are the correct parts they should work fine.

I've had cylinder rams bent enough I took them to a machine shop and had them straighten them. They put it in a press with brass to protect the ram. Came out fine!

That's good news. Looks like they are ~ $420 each.There are two part numbers. If it comes down to it, does anybody know which I need to buy for my loader? Thanks.

 

[TheOldHokie]

That's good news. Looks like they are ~ $420 each.There are two part numbers. If it comes down to it, does anybody know which I need to buy for my loader? Thanks.

At the risk of beating a dead horse - they are simple loader cylinders. Spend $300 for a pair of aftermarket cylinders. Measure carefully and they will work every bit as well as OEM at 3X the price.

Dan

 

[Pau7220]

With the risk of beating my dead horse... a quick google search of hydraulic shops near Berwick ME returned a 1/2 dozen. Walk into the shop with the rod just like it is. Have them replace the seals and straighten the rod.... believe me, they do it every day. Most cost effective way is the simple way... go directly to the source.

 

[wng-2]

With the risk of beating my dead horse... a quick google search of hydraulic shops near Berwick ME returned a 1/2 dozen. Walk into the shop with the rod just like it is. Have them replace the seals and straighten the rod.... believe me, they do it every day. Most cost effective way is the simple way... go directly to the source.

I took the cylinders and seal kits to the hydraulic shop Wednesday morning. They sent the rods to a machine shop to be straightened. I recieved a call yesterday afternoon to tell me the cylinders were ready. I reinstalled them this morning. Back in buiness. Thanks all.

 

[Lencho]

What was your cost?

 

[wng-2]

What was your cost?

$515 at the hydraulic shop, plus $80 for the seal kits.

 

[Pau7220]

Ouch! You got hit pretty hard. Here's my post from a year ago.

Jun 12, 2020

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Your best bet is to disassemble it and carry the piston and gland into your local hydraulic shop. Have them put the seals on for you. Check the rod for straightness before disassembly by turning it. I did mine right on the machine. My guys up here charged me $30.00 on a Friday at 3:30 for the 3 seals and o-rings.... and installed them!
If you're not able to do that just take them the cylinder.
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Clarification on the rod straightening.. the one I resealed I straightened with v-blocks in a press. The other one I unhooked the rod end and rotated it, marked the bent area, put a 4x4 under it, then slowly curled the bucket until I got it straight. Also note the bent rods were caused by broken dump stops... always check them.

P.S. I thought the $30 price tag was very unreasonable so I also gave him a $20 tip. Just having him roll the internal seal in the gland was worth that!

 

[lugbolt]

bent rams bind while in operation. The spec on bend is something like .015", so basically "not much" is allowed. That's one of many things I always checked (bend) when I was doing a bunch of cylinders. As long as they came apart easily, it was an inexpensive repair, typically labor under $100 + whatever parts cost. On average $175 roughly.

With that said if I had a bent ram, I replaced it or gave it back to the customer whichever he wanted. The ram shafts are plated and case hardened. When they bend, the "shell" becomes damaged and a lot of times would flake off with no warning whatsoever, even when they looked fine. When that happens the rod is junk, and it usually takes out both the dust seal and the main gland oil seal then you're back to square one. Real common on backhoes and loader tilt cylinders.