Attaching Backhoe Hydraulics

[JaysonJocelyn2022]

Would like to transfer a backhoe from a disabled Case 530CK to a fully functional Ditch Witch 8020 with trencher.

The 8020 is designed to have a backhoe attachment mounted to the front and hydraulics hooked to 3 quick attach ports in the front. Since I don't need the trencher that's currently mounted, I'd like to attach the backhoe to the rear and use the rear hydraulics that's currently running the trencher.

The trencher chain hydraulic drive is controlled by a lever on the main machine and the flow can be switched on/off/reverse but the pressure is a lot higher than what the backhoe is designed for.

Fabricating a mount is pretty straightforward but hoping to get some help with the hydraulics from someone more familiar with the variety/options of parts available.

Ditch Witch 8020 Hydraulic Specs

Backhoe Hydraulic Specs

Ditch Witch 8020 Hydraulic Schematics
.

Ditch Witch 8020 Hydraulic Flow Controls

H512 Trencher Attachment Hydraulic Schematics

Thanks in advance!!!

 

[BarnyardEngineering]

Generally speaking the three connections would be pressure, return, and case drain. The backhoe should only have a pressure and return. Case drains are usually only needed when a hydraulic motor is involved.

Should be as simple as figuring out which is which, and putting the correct quick connects on the hoses of the backhoe.

 

[caterpillar guy]

I'd bee more concerned with the front end not staying on the ground if you put the hoe on the back replacing the trencher unit. With the hoe on the front they sort of balance each other out. As for the lines just figure out the pressure and return or a place to return the oil from the hoe. Could be just a case drain for it.

 

[geok]

I would be also concern about breaking the ditch witch in half. If possible check weight difference between Ditch witch backhoe attachment and that of a Case
backhoe unit. Case backhoes can lift entire 11,000 lbs self off the ground. They have a solid frame from front to back.

 

[JaysonJocelyn2022]

(quoted from post at 05:16:12 02/08/23) Generally speaking the three connections would be pressure, return, and case drain. The backhoe should only have a pressure and return. Case drains are usually only needed when a hydraulic motor is involved.

Should be as simple as figuring out which is which, and putting the correct quick connects on the hoses of the backhoe.

Appreciate the information and as a worse case scenario, I'll use the front attachment ports but was hoping to use the rear hydraulics.

 

[JaysonJocelyn2022]

Not really concerned with the weight issue, the base 8020 outweighs the base 530 by over 1000 lbs. One of the rear attachment for the 8020 weighs 3000 lbs. The Ditch Witch is a much larger unit. Couldn't find the weight of the backhoe attachment, do you have a guess?

This post was edited by JaysonJocelyn2022 on 02/09/2023 at 04:39 am.

 

[wp6529]

Don't confuse pressure and flow, the pressure (PSI) is what you need to be concerned with. The backhoe spec looks like it's rated for 2250 PSI, and I don't see specs on the Ditch Witch but if it's more modern the pressure is likely higher and that would be the issue.

Depending on what else hydraulic is on the Ditch Witch you might be able to just lower the relief valve setting on the Ditch Witch to bring it down to 2250 to be safe for the backhoe.

Are you selling the trencher attachment? I could use one here if you're not too far away and the price is right. I have machines I could adapt it onto.

 

[JaysonJocelyn2022]

Yeah, guess the images get compressed and might not be able to read the schematics. Ports I want to attach to are 5000 PSI. The flow is continuous and controlled by the lever in the color photo. Do they make a relief valve that would drop the 5000 PSI to what I need for the backhoe?

I'm off grid Alaska so selling the trencher is kinda out of the question. Hence the frankin-monster equipment I build to get the job done

This post was edited by JaysonJocelyn2022 on 02/09/2023 at 08:24 pm.

 

[wp6529]

(quoted from post at 00:22:53 02/10/23) Yeah, guess the images get compressed and might not be able to read the schematics. Ports I want to attach to are 5000 PSI. The flow is continuous and controlled by the lever in the color photo. Do they make a relief valve that would drop the 5000 PSI to what I need for the backhoe?

I'm off grid Alaska so selling the trencher is kinda out of the question. Hence the frankin-monster equipment I build to get the job done

This post was edited by JaysonJocelyn2022 on 02/09/2023 at 08:24 pm.

The Ditch Witch is almost certainly not running 5000 PSI hydraulics. The really big $$$$ excavators do, but highly unlikely for a Ditch Witch. 5000 I presume is a rating on the hose or a coupler.

From the first pic you posted that doesn't have column headings it looks like it's probably running at 2500 PSI, so you should be able to adjust the existing relief valve down to the 2250 the backhoe is rated for and have minimal impact on other functions.

It's not a big pressure difference and the backhoe would probably be fine at 2500 PSI, but I don't like running things over their rated pressure.

Off grid Alaska would be nice, except I've never been cold weather compatible and am getting less so the older I get. Under 70F I start to complain and anything below freezing is a nightmare.

 

[JaysonJocelyn2022]

(quoted from post at 04:28:38 02/10/23)

(quoted from post at 00:22:53 02/10/23) Yeah, guess the images get compressed and might not be able to read the schematics. Ports I want to attach to are 5000 PSI. The flow is continuous and controlled by the lever in the color photo. Do they make a relief valve that would drop the 5000 PSI to what I need for the backhoe?

I'm off grid Alaska so selling the trencher is kinda out of the question. Hence the frankin-monster equipment I build to get the job done

This post was edited by JaysonJocelyn2022 on 02/09/2023 at 08:24 pm.

The Ditch Witch is almost certainly not running 5000 PSI hydraulics. The really big $$$$ excavators do, but highly unlikely for a Ditch Witch. 5000 I presume is a rating on the hose or a coupler.

From the first pic you posted that doesn't have column headings it looks like it's probably running at 2500 PSI, so you should be able to adjust the existing relief valve down to the 2250 the backhoe is rated for and have minimal impact on other functions.

It's not a big pressure difference and the backhoe would probably be fine at 2500 PSI, but I don't like running things over their rated pressure.

Off grid Alaska would be nice, except I've never been cold weather compatible and am getting less so the older I get. Under 70F I start to complain and anything below freezing is a nightmare.

The trencher chain drive runs off the "ground drive" circuit.

So guess I'll have to run it off the front quick connect ports with some super long hoses.

Which ports do I hook to the backhoe inlet/outlet? Do I use the "Power Beyond" port?

Front ports are rated 15.5 GPM @2000 PSI, does this mean I'll have to run the motor at full throttle?

Backhoe Specs
Thanks for all the help.

 

[BarnyardEngineering]

You would use the pressure and return ports.

 

[JaysonJocelyn2022]

(quoted from post at 15:55:50 02/10/23) You would use the pressure and return ports.

Thank you.