Log splitter hydraulic questions, dump valve and pressure setting

[Socalmisfit]

So I want to put a dump valve on my splitter, I kind of get how the system works and I believe all the return oil flows through the log lift side of the system. All those hoses are smaller so more restriction. By the looks of it I would hook a & b from the cylinder to the dump and then into the return if I’m understanding it right. I’m wanting to add the dump for faster recoil and help to keep the oil cooler. I understand I’m gonna still have heat but if I can shove it straight back to the tank and not through the detents it should help a little.
Next question my pump pressure can’t be set, it is set through the detent and the valve has a fixed pressure of 2000 psi. If I got a different valve could I then adjust the pressure up, or buy a valve with a higher fixed rate? Like I said I am new to hydraulics and I get the basics. I also understand the less restrictions I have in the system the cooler the system runs, and that’s what I am trying to accomplish.
I also understand that I can put a 5” ram and get a higher splitting force, but a valve is cheaper than a ram. I’m not exactly sure how much more force 500-1000 more psi would make but if it would get what I’m looking for I would like to try it. I know adding more pressure puts more of a working load on the cylinder but if the cylinder is rated at 3000 I’d like to be somewhere from 25-2800.
I don’t run an auto cycle so I will be there to make sure stuff don’t get tore up with the added force. Just want to get a little more out of the system with out the huge cost of a bigger ram. If after doing these upgrades, if I’m on the right path and they can work, and I’m still looking for more than a bigger cylinder it is. After that I’ll have more questions about the oil cooler I will need thanks guys.

 

[Deets066]

Your power is dictated by the ram, pumps and valves will gain you speed.

You should have a separate return for the log lift and for the ram.

 

[Deets066]

This is how I have mine setup.

 

[Socalmisfit]

Your power is dictated by the ram, pumps and valves will gain you speed.

You should have a separate return for the log lift and for the ram.

So both run into 1 filter on top of tank on mine. I see it now the main runs into the pressure regulator for the lift. 1 comes out to the tank the other goes into the lift detent which comes out into the tank. I can run a tee off of the ram on front and hook into the side with the line off of the detent and run off of the back or that T to the dump. Same on the back, T off of the cylinder run the detent hose into the T, and out of the T, goes to the dump. From the dump I can run it into the return line off of the back of the pressure valve. I would just make that line bigger.
Now for an oil cooler. I can run off of the lift detent out, into cooler and from cooler into filter? Or should I run both lines into the cooler then to the filter and dump in front of the cooler through the filter? If that makes sense
Here are some pics of how my systems ran. Thanks for the pics. Oh yeah, where did u get that temp gauge that’s *b-wordin bro.

 

[Deets066]

I didn’t run out of the dump through the cooler, didn’t want to slow the flow down.
What pump and engine do you have?

 

[Socalmisfit]

I didn’t run out of the dump through the cooler, didn’t want to slow the flow down.
What pump and engine do you have?

22 Gpm 2 stage, with a 14hp Koehler

 

[Socalmisfit]

Your power is dictated by the ram, pumps and valves will gain you speed.

You should have a separate return for the log lift and for the ram.

So your valves are adjustable, you can set the psi on your system. My ram valve is fixed psi, non adjustable, the psi is fixed at 2000 psi. I can get the valve that goes in it to make it adjustable and then could add pressure to the system. So at 2000 psi with a 4” ram and a 2” rod you get 25000 lbs. 2500 psi gives u 31000 lbs, 2800 psi gives u 35000. 500 psi gives me 6000 lbs, that could help crack open some of this nasty euc I’m having trouble with.
My motor doesn’t labor at 2000 psi it just relieves the pressure, so at 2500 I’m thinking it should be ok. I understand it will put more strain on the system, but the system is rated at 3000 psi, and I f the temps get up where it may be a problem. At that time I could add the cooler and hopefully be good. Then the dump valve would give me a slight faster recoil time all a plus in my book.
How much psi are you running on your system? On your log lift and wedge lift valves, how did you adjust the pressure for them to be manageable, speed wise? I know it I turn up the flow control valve on mine the lift speed is nuts.
I think I got it figured out, I’m gonna order the relief valve so I can try and turn up the pressure. I guess u can add shims to adjust pressure on a fixed valve but I would just rather it be adjustable. This is my first big splitter, my next one will have a 5” ram with a 28 gpm pump, and a bigger motor so I can get the bigger numbers, and keep up the cycle times. But spending 32$ on a valve, to see if I can get what I’m looking for, is a lot cheaper that a new ram.
Thanks again for the pics and the input I do appreciate it.

 

[Grimmy]

On a 22gpm system, you should calculate what the gpm of the oil coming out of the cylinder on the return stroke is. If you valve is rated for that gpm, then adding a dump valve will do nothing for your return speed. You might lose a little heat, but I doubt it would be that much. Only way to get a faster return, get a bigger rod. My return stroke on my 5" cylinder, produces about 63gpm, therefore I had to have a dump valve. I think I also had 25gpm valves for my 4 way and lift table installed, as I wanted the oil to heat up. I do run an oil cooler, but it was designed and built with it, not added later.

I think you'd be wasting your time and money trying to add this, and you wouldn't gain anything. If you want it faster, you have to pay.....just no way around it. And you want it safe.

 

[Deets066]

On a 22gpm system, you should calculate what the gpm of the oil coming out of the cylinder on the return stroke is. If you valve is rated for that gpm, then adding a dump valve will do nothing for your return speed. You might lose a little heat, but I doubt it would be that much. Only way to get a faster return, get a bigger rod. My return stroke on my 5" cylinder, produces about 63gpm, therefore I had to have a dump valve. I think I also had 25gpm valves for my 4 way and lift table installed, as I wanted the oil to heat up. I do run an oil cooler, but it was designed and built with it, not added later.

I think you'd be wasting your time and money trying to add this, and you wouldn't gain anything. If you want it faster, you have to pay.....just no way around it. And you want it safe.

Won’t a larger cylinder return slower?

 

[Al Smith]

On my home built it is a 5" cylinder and it very seldom shifts into high pressure .It's not quite as fast of course as a 4" cylinder but it's faster than I can stuff wood in it .With a 5" and 8-10-12 gallons of Dextron it doesn't get hot ,every thing is tubed up with 3/4" lines ,no need for a cooler .I've seen 4" cylinder models running ballz to the wall the cylinder gets so hot you could fry an egg .

 

[Grimmy]

Won’t a larger cylinder return slower?

Most will, but there are some bigger piston cylinders that have a bigger rod. Rod diameter determines how fast it can return.....along with what valves, hoses.....and port sizes.

 

[Pincher]

I would like to see a pressure gauge between the main valve and the flow control. It appears the return to tank line from the flow control looks small for being fed by a -12 (3/4") inlet hose. Might be a cause of heat if you are having issues.

 

[Socalmisfit]

I would like to see a pressure gauge between the main valve and the flow control. It appears the return to tank line from the flow control looks small for being fed by a -12 (3/4") inlet hose. Might be a cause of heat if you are having issues.

I got it figured out. I added 2 washers in front of the spring and got the psi up to 2800. Splitter livened up and the temps are down since it isn’t by passing as much. Ran it day before yesterday for 3 hrs and temps were sitting at 150. It is colder weather, but before that I ran it for 4 or more hrs and never ran over 175. As it is now I am super happy with it, when I have some extra cash I might still throw a dump valve in it just so I can get a faster recoil to get the pusher out of the way faster.

 

[Ontario Firewood Resource]

Custom 35 ton high output log splitter to be resurrected...