Who's Online Now
0 registered members (), 1 guest and 41 spiders.
Key: Admin, Global Mod, Mod
Newest Members
Resurgence, Cobra2411, Patrick, Humberto, Schue
341 Registered Users
Forum Statistics
Forums23
Topics278
Posts2,883
Members341
Most Online248
Mar 14th, 2020
Popular Topics(Views)
31,961 77-MGB
26,749 2020 Gardens
Top Posters(All Time)
JIM 816
sonny 803
GatorS 239
Nnaatz 149
GLyford 73
Doc 68
chma 43
January
S M T W T F S
1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 31
Previous Thread
Next Thread
Print Thread
Rate Thread
Valve/pump selection #2761 11/14/2021 07:35 AM
Joined: Sep 2021
Posts: 6
D
Dave60 Offline OP
MBN newbie
OP Offline
MBN newbie
D
Joined: Sep 2021
Posts: 6
Hello all, I have started a towable backhoe project and looking for input on on 4 spool valve and pump selection. I am somewhat ignorant about hydraulics although I did build a FEL for my tractor that works fine. I had some plans from PF Engineering for that build. This project is my own design so I have a lot of doubts. Any recommendations out there for valves/ pumps and sources for them? Thanks!

Re: Valve/pump selection [Re: Dave60] #2762 11/14/2021 08:37 AM
Joined: Jan 2019
Posts: 73
GLyford Offline
MBN member
Offline
MBN member
Joined: Jan 2019
Posts: 73
For a towable, I suspect anything over 2 GPM (at your rated engine speed) will be fine.

Running higher pressures is the simplest way to get better performance, so if everything else in the system is rated for at least 2000 psi that's a good place to start. So that has to be all the hoses, cylinders and fittings, not just the pump and valve...lowest rating sets your safety limit.

Do you have an engine yet? If you are starting with a certain horsepower, go with the pump size suggested by https://www.surpluscenter.com/tech-help/tech-help-home/ They are pretty simple and straightforward and cover most of the basics pretty well, also their prices are reasonable, especially on hoses.

Most valves will start at about 10 GPM in size, which will probably work pretty well for you. As a general rule, you want the valve rating no smaller than the pump output, but something that is still close is better than a huge valve with a tiny pump, but they only go so small so at some point you just have to go with what you can get.

And lastly, if you find something moves too fast to be easily controllable after you build your machine, remember that you can always slow something down in either one direction or both with a needle valve. Something that moves how you expect it when you pull the handle is better than always trying to feather the valves and forgetting half the time and sending the bucket slamming into things.

Have fun, and remember, if something really isn't working, you can always change it, that's the joy of building your own machines.

Re: Valve/pump selection [Re: Dave60] #2763 11/14/2021 08:52 AM
Joined: Sep 2021
Posts: 6
D
Dave60 Offline OP
MBN newbie
OP Offline
MBN newbie
D
Joined: Sep 2021
Posts: 6
Thanks for the information! I do not have a engine yet but my plan is to use four 2-1/2 x 16 x 1.5 hydraulic cylinders. I thought I would have to select engine size to match pump and valve so I haven’t committed to anything yet. Does a mono block valve work for this or is sectional valve required?

Re: Valve/pump selection [Re: Dave60] #2764 11/14/2021 11:39 AM
Joined: Jan 2019
Posts: 73
GLyford Offline
MBN member
Offline
MBN member
Joined: Jan 2019
Posts: 73
As long as you have all the functions you want, in the order you want, either will work fine.

Re: Valve/pump selection [Re: Dave60] #2766 11/14/2021 12:11 PM
Joined: Jan 2019
Posts: 816
JIM Offline
MBN old hand
Offline
MBN old hand
Joined: Jan 2019
Posts: 816
How big you making this thing? I'm Running 2X8X1.25 cylinders on my mini hoe.
[Linked Image from live.staticflickr.com]


I know a lot about a lot of things BUT I still have a lot to learn.
Life is what you make of it. So, why not make a working machine to make it easier.
Re: Valve/pump selection [Re: Dave60] #2768 11/14/2021 02:47 PM
Joined: Jan 2019
Posts: 803
sonny Online Content
MBN old hand
Online Content
MBN old hand
Joined: Jan 2019
Posts: 803
I used what I had in a big scrap pile to make this towable unit.
It digs a little over 17 feet deep and you can load over tandem trucks with it if needed. I have 2 buckets for it, and the little 12 inch is on it in the pic. The other bucket is 25 inches or so wide and the hoe handles it with ease.
I used an old valve bank off of a junked hoe and the cylinders also came from it.
The pump came off a MM combine, and is not all that big but had a high volume to it. I had to go with 2-wire hoses after I started to use the hoe. It would blow 1-wire hoses after a while when you started crowding it,--(which we all do), so 2-wire solved that problem for me.
As for the motor/pump setup,---a single B section belt drives it from the back of the engine which came off an Oliver 525 combine. Its a Chrysler industrial 230 flathead 6. My main reason for using it was that I needed counterweight!

Attached Files
20201201_111034.jpg (69.68 KB, 15 downloads)

"A machine you build yourself is a vote for a different way of life. There are things you have to earn with your hands."
Re: Valve/pump selection [Re: Dave60] #2769 11/15/2021 08:32 AM
Joined: Jan 2019
Posts: 386
B
bunkclimber Offline
MBN enthusiast
Offline
MBN enthusiast
B
Joined: Jan 2019
Posts: 386
Originally Posted by Dave60
Does a mono block valve work for this or is sectional valve required?


Dave you can use either one 4-spool monoblock valve with 4spools/sections or two sectional valves but then you get into inter-valvebody reliefs and it gets complicated.To use two seperate valves in series you'll need a separate pressure relief valve inbetween the two monoblock valves with a separate return hose back to the tank for the relief.

You really shouldnt series feed separate valves because of pressure doubling that happens when you unload one spool into another charged spool..an easy way to use two valves is to convert the first into a power-beyond valve,some you can some you can't with a conversion plug that goes into the side of the valve. Ive built a LOT of hydraulic equipment and I think if I was going to build a hoe,i would use the Prince backhoe valve,

Prince Backhoe valve

its a bit pricey at around $900 but does give you the whole backhoe shebang in one compact double-joystick valve package with minimal accessories required,and it makes for a very neat package hydraulically and with two valves just for your stabilizers.When you $$ total up all the hardware the valves can run you big bucks unless you're getting them for free-but its also the part you touch and interface with the most and makes a tremendous difference in how the machine will work for you.
FWIW,and thats my opinion, but your mileage may vary and as always batteries are not included lol

Surplus Center is a good place to shop for parts,valves,pumps and fittings for a hydraulic project,they do have it all..Once again my advice is when you order hydraulic fittings or adapters, if you need two, then purchase 4, put two in a drawer because WHEN (not if,) you need one more, you have one, not having to wait two weeks and pay $15.00 for shipping on a $3.50 part is priceless..been down that road many times.
Best of luck with this,take pics and let us know how you do


Recent Topics
Wheel bushing question
by sonny - 01/18/2022 12:10 PM
What Odd Job Did you Do Today?
by bunkclimber - 01/18/2022 03:08 AM
Troy Built Tillers
by JIM - 01/17/2022 09:15 PM
Back With Cyclone Rake Questions
by sonny - 01/16/2022 02:38 PM
weather pix.
by JIM - 01/16/2022 08:35 AM
F-700 bucket truck
by sonny - 01/15/2022 03:48 PM
motor selection
by Old as Dirt - 01/15/2022 10:56 AM
1978 f250 4x4 rebuild
by JIM - 01/15/2022 06:48 AM
Eager Beaver 2.0 Chainsaws
by sonny - 01/12/2022 02:43 PM
SLOW PROGRESS
by JIM - 01/02/2022 07:10 PM
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Today's Birthdays
There are no members with birthdays on this day.
Donation Box
Powered by UBB.threads™ PHP Forum Software 7.7.3