wood splitter

[ron65]

JJ, I agree with you. My suggestion to hold the lever long enough is based on partial engagement of spool valve will allow low flow and low pressure readings until resistance is met. Continueing to hold the lever engageing the spool will let pressure built to relief setting, albeit somewhat slower than if the spool was completely engaged. Once total resistance is met pressure should rise pretty fast. As I under stand it, his switching of the hoses to the cylinder, the system will build full pressure on both sides of the cyl piston, depending on which end he currently has the hoses connected to. I think that eliminates the cylinder as the problem since he has stated system pressure at both ends of the cylinder. The pump is building system pressure as set by the relief at 2000psi, You are right, if the relief works in one direction,it will work in the other direction, the oil flows over the relief in the same direction, requardless of which direction the spool is centered. I think that narrows it down to either a defective control valve, or improper plumbing. The problem seems to be only on one port/direction of the control valve, could be a crack internally allowing oil to flow back to tank which would negate any attempt to adjust pressure at the relief.

Thanks for stepping in muddstopper. I do have the tee with the gauge installed between the pump and valve. It is right at the 3/4" inlet to the main valve housing. I only moved it to the extend port to make the test Leejohn had suggested. I have also kept the lever engaged for a long time to see if it would build higher than the usual 5-600 psi, but it does not.

Now in reading both your posts and J_J's recent posts, I may be at fault for saying something in my testing results which is not true, but you are taking for granted it is true. And I do not know if it even makes a difference to your finding a solution, but J-J, in your recent post you said: "The gage came from the factory set to 2000, so it appears the relief valve is working and relieving at 2000 psi." That is not really true, whenever I am testing and the pressure goes up to 1500-2000 psi I have always stopped what I was testing, thinking I might bust something. So I do not know if the main relief is really working. All I know about that relief is I can screw it in or back out and I will always get the same slow build up to 5- 600 psi. While in other tests the pump, cylinder, and 3 of the 4 ports have tested 1500-2000 psi. very quickly.

When I can switch and test the log lift spool on the main cylinder, do you want me to rev the engine and see how high the pressure will go since I know the log lift spool has show me it easily hits 1500-2000. Would I damage anything or would it just kill the engine?

Thanks

 

[J_J]

If the relief is working, it will not kill the engine as you are relieving at 2000 psi and at that pressure, you are not using all the the engine HP.

Your engine and your pump was selected to provide the specified GPM and pressure.

At 3.4 GPM and 2000 psi, you are using only 5 HP.

By the way, your detent is preset to 1200 psi, and the adjustable main relief is from 1500 to 3000 psi. When the cyl is maxed out at the indicated 2000 psi, turn the main relief in and the pressure should rise. You are simply tighten the spring on the relief valve to provide more force, if the cyl can make that force.

The speed of the engine only controls the GPM. The resistance to the flow dictates the pressure.

Yes, hold the lever to maximum to get the maximum pressure allowed by the relief valve.

You might check the load checks valve on the log splitter spool. That is under the hex plug between the work port. When they go bad, you get strange results.

Check the poppet, spring and the seat for debris.

 

[Leejohn]

I think the spool isn't getting moved far enough or it's the wrong spool or body is cracked.

 

[J_J]

Again, the spool position does not matter.

Any flow will fill the cyl and when it meets resistance, the pressure will build up until the relief pressure is met.

GPM's determines the speed of operation. Pressure determines the force.

 

[J_J]

Again, the spool position does not matter.

Any flow will fill the cyl and when it meets resistance, the pressure will build up until the relief pressure is met.

GPM's determines the speed of operation. Pressure determines the force.

 

[muddstopper]

I think the spool isn't getting moved far enough or it's the wrong spool or body is cracked.

JJ is correct, it doesnt matter how far the spool is moved, it still should build maximum pressure, it will just take longer because of restricted flow. I am leaning toward valve problems myself, but I just skimmed thru the threadt. I am going to reread the thread before commenting further.

edit,
after further review, unless the splitter has a dump valve plumbed in the system, and it plumbed wrong. I still think it is a valve problem. As far as factory relief setting on the valve, it doesnt matter (for testing purposes), if its set at 2000 or 3000psi, You still should see the same pressure in either direction the valve lever is activated. When you change hoses at the cylinder,the problem moves with the changes. You have pressure at the pump, your cylinder will allow pressure build at each port, only thing left is the valve. With that said, if the splitter has a dump valve to allow oil to bypass the control valve on return stroke and it was plumed on the wrong line, then pressure could be flowing thru the dump valve back to tank, not allowing full pressure to build. I doubt a splitter with a 11gpm pump has a dump valve, but it is a possibility. The control valve should have a in, (pressure),out, (tank) and 4 ports, one port for each port on the two cylinders. Is anything else plumbed into the system?

 

[ron65]

If the relief is working, it will not kill the engine as you are relieving at 2000 psi and at that pressure, you are not using all the the engine HP.

Your engine and your pump was selected to provide the specified GPM and pressure.

At 3.4 GPM and 2000 psi, you are using only 5 HP.

By the way, your detent is preset to 1200 psi, and the adjustable main relief is from 1500 to 3000 psi. When the cyl is maxed out at the indicated 2000 psi, turn the main relief in and the pressure should rise. You are simply tighten the spring on the relief valve to provide more force, if the cyl can make that force.

The speed of the engine only controls the GPM. The resistance to the flow dictates the pressure.

Yes, hold the lever to maximum to get the maximum pressure allowed by the relief valve.

You might check the load checks valve on the log splitter spool. That is under the hex plug between the work port. When they go bad, you get strange results.

Check the poppet, spring and the seat for debris.

Thanks J-J I will see if I have time tomorrow to test these things out.

 

[ron65]

JJ is correct, it doesnt matter how far the spool is moved, it still should build maximum pressure, it will just take longer because of restricted flow. I am leaning toward valve problems myself, but I just skimmed thru the threadt. I am going to reread the thread before commenting further.

edit,
after further review, unless the splitter has a dump valve plumbed in the system, and it plumbed wrong. I still think it is a valve problem. As far as factory relief setting on the valve, it doesnt matter (for testing purposes), if its set at 2000 or 3000psi, You still should see the same pressure in either direction the valve lever is activated. When you change hoses at the cylinder,the problem moves with the changes. You have pressure at the pump, your cylinder will allow pressure build at each port, only thing left is the valve. With that said, if the splitter has a dump valve to allow oil to bypass the control valve on return stroke and it was plumed on the wrong line, then pressure could be flowing thru the dump valve back to tank, not allowing full pressure to build. I doubt a splitter with a 11gpm pump has a dump valve, but it is a possibility. The control valve should have a in, (pressure),out, (tank) and 4 ports, one port for each port on the two cylinders. Is anything else plumbed into the system?

muddstopper

Made a comment earlier to you but do not see it so will try again. I do not have a dump valve or anything else plumbed into the system. It is a very simple system. Oil from the holding tank, to the pump, to the tee and gauge next to the main valve, then into the main valve, then out the other side of main valve, then through the filter, then returning to the holding tank.

 

[muddstopper]

I didnt think you would have one, but just wanted to make sure.

 

[ron65]

If the relief is working, it will not kill the engine as you are relieving at 2000 psi and at that pressure, you are not using all the the engine HP.

Your engine and your pump was selected to provide the specified GPM and pressure.

At 3.4 GPM and 2000 psi, you are using only 5 HP.

By the way, your detent is preset to 1200 psi, and the adjustable main relief is from 1500 to 3000 psi. When the cyl is maxed out at the indicated 2000 psi, turn the main relief in and the pressure should rise. You are simply tighten the spring on the relief valve to provide more force, if the cyl can make that force.

The speed of the engine only controls the GPM. The resistance to the flow dictates the pressure.

Yes, hold the lever to maximum to get the maximum pressure allowed by the relief valve.

You might check the load checks valve on the log splitter spool. That is under the hex plug between the work port. When they go bad, you get strange results.

Check the poppet, spring and the seat for debris.

J-J

Had a short time to work on the splitter this morning. (I thought if I retired I would not have any more dead lines Removed hoses from log lift side of valve and replaced them with hoses from the main cylinder. Levered in and out and seems to work perfectly in both directions. Been cold around here and oil was a little thick but the gauge read 1500 psi at either end of the piston stroke. Fairly fast up to 1200 psi and then slower build up to 1500 psi. Did not have time to try and raise the main relief psi. What do you think, new valve?