Cat Backhoe Hydraulic Valve Question

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I have a mid 80’s Cat 426 backhoe that needs the rear 6 valve assembly that operates the hoe. I know the Cat valves are different than most other manufacturers since they have resolvers. These valves are very difficult if not impossible to find used, and a new one cost more than the backhoe is worth. My question is, can you use an aftermarket valve or a valve off another brand hoe such as Case or Ford 555 on a Cat backhoe? Just trying to see what my options are. Thanks!

 

[Nige]

The valve comes as 6 individual sections. Are they all bad.?
If they are leaking can't they be re-sealed.?
Have you tried finding a used valve assembly based on Part Number.?
if you don't know what the Part Number of the assembly is post your machine Serial Number and we can figure it out.

 

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I have searched for a used valve assembly with no luck. The boom section of my valve is definitely bad. The other sections are working but might possibly be damaged as well. When I bought the hoe, it had a brand new pump on it. The previous owner kept turning up the pressure as the older pump got weaker. After the pump got weaker and he couldn’t turn the pressure up any more, he then decided to put the new pump on. Only thing is, he didn’t turn the pressure back down for the new pump. He lived close to the beach with sandy soil so he probably never stalled the pump. I bought the hoe and transported it 100 miles inland to hard red clay rocky soil. While pushing over a 18” diameter tree, I stalled the pump and the pressure must have skyrocketed to the point it ballooned the “not sure the technical name” but the silver test tube looking things inside the sections. They are machined for each section so once they get damaged, the section is useless. I would feel better buying a whole new aftermarket valve or one from another backhoe brand if they could be made to work.

 

[ahart]

What’s the serial number of your machine?

 

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What’s the serial number of your machine?

Serial # 7BC 02300

 

[ahart]

9T-7938 is part number for the 6-bank valve. If you google “machinery trader parts” you can enter that part number in and see listings. There’s a few places we deal with that show one, Pickett Equipment is one of them and they typically have decent take off components. Another place you might try is Crowe equipment, they’re also a dismantler that’s here in Indiana. I would expect to be in the vicinity of $3000 for that valve, they might come off of it for a little less as there’s probably not a lot of demand.

 

[Link]

9T-7938 is part number for the 6-bank valve. If you google “machinery trader parts” you can enter that part number in and see listings. There’s a few places we deal with that show one, Pickett Equipment is one of them and they typically have decent take off components. Another place you might try is Crowe equipment, they’re also a dismantler that’s here in Indiana. I would expect to be in the vicinity of $3000 for that valve, they might come off of it for a little less as there’s probably not a lot of demand.

Thanks.. I’ll check both of them out. But to my original question, will only a Cat valve work or will any valve that will handle the same pressure work?

 

[Nige]

But to my original question, will only a Cat valve work or will any valve that will handle the same pressure work?

Only a Cat original valve will work. Each manufacturer designs systems to work with their parts, not anybody else's. The resolver network in the Cat valve bank is also somewhat unique.

Attached is a parts breakdown for the Valve Group for your Serial Number. I also included a breakdown of one of the sections so you can see what's available as spare parts. The sections are all slightly different internally BTW.
Are the "the silver test tube looking things" Item Ref # 18 on Page 3 by any chance.?

 

[Link]

Only a Cat original valve will work. Each manufacturer designs systems to work with their parts, not anybody else's. The resolver network in the Cat valve bank is also somewhat unique.

Attached is a parts breakdown for the Valve Group for your Serial Number. I also included a breakdown of one of the sections so you can see what's available as spare parts. The sections are all slightly different internally BTW.
Are the "the silver test tube looking things" Item Ref # 18 on Page 3 by any chance.?

No that isn’t it. The tube I am talking about is not on that drawing. That looks like a different section but if you removed the plug (part #13) the tube would be down in there. I believe it sets on a spring and is pushed down by hydraulic pressure and rises by the spring’s resistance. You normally can pull the tube out with your finger but I believe excessive pump pressure ballooned mine and caused it to swell against the valve wall preventing it from moving. I’ll try to get a picture.

 

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Only a Cat original valve will work. Each manufacturer designs systems to work with their parts, not anybody else's. The resolver network in the Cat valve bank is also somewhat unique.

Attached is a parts breakdown for the Valve Group for your Serial Number. I also included a breakdown of one of the sections so you can see what's available as spare parts. The sections are all slightly different internally BTW.
Are the "the silver test tube looking things" Item Ref # 18 on Page 3 by any chance.?

Attached is a photo of the part I am referring to. There is no part number because you can’t buy separately from the valve.

 

[Nige]

Right. Gotcha. I see what you’re talking about now.

Another option would be to look for each section of the valve separately. The Part Numbers are all listed on Page 2 of the attachment I posted above.