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Hydraulic Thumb/Hammer (Plumbing Recommendations?)

Pdexter1210

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Dec 20, 2024
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Drexel, MO
I have a Kobelco SK230SRLC-3 that has 1 set of auxiliary 2-way hydraulics plumbed to the stick. I have purchased a quick coupler, hydraulic hammer and a main pin hydraulic thumb for the machine, and setting it up to run everything is the winter project. My question relates to plumbing/connecting/disconnecting the hammer and thumb. I have been studying other setups and how they have run the plumbing for the thumb. Some add an auxiliary block and an additional valve near the top of the auxiliary line (looks like a code 61 port spacer with an auxiliary port in the first pic), and some pull from the valve at the bottom. The drawback to pulling from the valve at the bottom seems two-fold to me, first it's a very large valve relative to what the thumb needs and it's only a 2-way valve, so there would be lots of changing to go back and forth from thumb to hammer. I am thinking about buying a 3-way valve and replacing the bottom valve and plumbing both the thumb and hammer fittings to the 3-way valve ports. This way I would have 1 point of on/off switching to go from hammer to thumb, vs. two with the additional valve installed near the top of the stick. So my question here is, for those who have used different setups, what are the pros/cons of the different setups? Thanks.
 

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92U 3406

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A 3 way valve at the bottom of the stick on each side is fine.

Where you might run into issues is if you do not have the ability to program multiple attachments or switch to 1 way flow. Not a huge deal, just requires some additional plumbing. Kobelco aren't common around here so I don't know how they're setup from factory.
 

skyking1

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different breed of machine, but I ran a dedicated return line for the 1 way device ( compactor in my instance).
3 way valves where you describe them to lock off the thumb. No fancy flow choosing in the old 120 so it just works.
 

Pdexter1210

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Drexel, MO
Thanks, the machine has programming for nibbler and hammer modes, so I think I should be good on that front. The 3-way valve seemed more efficient to me, but I have seen so many with the aux block at the top and the additional shut off valve for the thumb that I thought I better ask, in case I was missing something important. Appreciate the responses.
 

tylermckee

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781
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washington
I like a 3 way valve like pictured here, top picture. This machine had the upper 3 way valve and additional hose/hard line to a valve at the bottom of the stick. I got rid of that additional valve as in my experience you're far more likely to wipe out your quick couplers if their at the end of stick. Plus on this machine in particular you had to have a 45 between quick coupler and valve for the hydraulic hose to clear the thumb and thumb linkage.
 

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92U 3406

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May want to verify that the machine has a diverter valve on the aux return side to switch between 1 way and 2 way flow. Have seen some machines show it in the display but not actually have the electronically controlled valve installed.

Have also seen the valve stick in the bore sometimes due to lack of use for years. I would definitely verify that your back pressure on the return side is no more than about 175-200 PSI, lower is better. Hammer's manual should list all the info related to proper setup. Nothing wrecks a hammer quicker than having excessive back pressure. Usually blows out the lower piston seal.
 

Pdexter1210

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Joined
Dec 20, 2024
Messages
24
Location
Drexel, MO
I like a 3 way valve like pictured here, top picture. This machine had the upper 3 way valve and additional hose/hard line to a valve at the bottom of the stick. I got rid of that additional valve as in my experience you're far more likely to wipe out your quick couplers if their at the end of stick. Plus on this machine in particular you had to have a 45 between quick coupler and valve for the hydraulic hose to clear the thumb and thumb linkage.
Thanks, this is very similar to the setup I had in mind. That looks like an Anchor Fluid Power 3-way valve on your setup? Do you happen to know what size that is? My two-way valves have a 22mm through hole but best I can tell they are SAE #20 fittings (1-1/4") which seems like overkill. The #16 (1") valve seems to have a large enough through hole to be adequate, 5075psi rating and 53gpm so say the specs, and they are about half the price of the 1-1/4.
 

tylermckee

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Thanks, this is very similar to the setup I had in mind. That looks like an Anchor Fluid Power 3-way valve on your setup? Do you happen to know what size that is? My two-way valves have a 22mm through hole but best I can tell they are SAE #20 fittings (1-1/4") which seems like overkill. The #16 (1") valve seems to have a large enough through hole to be adequate, 5075psi rating and 53gpm so say the specs, and they are about half the price of the 1-1/4.
Not sure on the brand. Through hole bolts on this are undersized IMO, have broken them a bunch of times running a breaker. This one has #20 (1.25") but it's on a Hyundai hx330, I'd imagine 1" would be fine on a smaller machine
 

skyking1

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May want to verify that the machine has a diverter valve on the aux return side to switch between 1 way and 2 way flow. Have seen some machines show it in the display but not actually have the electronically controlled valve installed.

Have also seen the valve stick in the bore sometimes due to lack of use for years. I would definitely verify that your back pressure on the return side is no more than about 175-200 PSI, lower is better. Hammer's manual should list all the info related to proper setup. Nothing wrecks a hammer quicker than having excessive back pressure. Usually blows out the lower piston seal.
Hence that 3rd line on the 120 right back to the tank. It was factory kit.
 
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