Log splitter not building pressure

[pdqdl]

None of those corrections would account for the hydraulic fluid blowing out the tank vent, guys.

THINK!

 

[CJ1]

Op said he changed the valve, same problem. Said has new cylinder. Putting my money on the 2 stage pump. jmho OT

The pump does not care if it is pressuring A or B line. In this case you either have a work port relief messed up OR a cylinder bypassing internally. A spool valve not shifting completely will cause this also. New parts does not rule out that they are not bad. Especially now that most of this crap is made in China. A $10 pressure gauge would find the problem fairly quick. But again I have played out this same situation more times than I can count. Second hand info is hard to get a 100% picture. I would say 90% of the time I can get a customer fixed over the phone IF we get accurate info. The other 10% has to be hands on. As far as the engine stalling, at what pressure? There are at least 8 different displacement pumps out there and the smallest one I know of Is a 9gpm in the high side and they all basically look alike, a 5hp Honda would run it if as was said the high / low switch point is adjusted right. You put a 16gpm pump on that honda and you will get just what the op is saying. That pump needs a 13hp. CJ

 

[CJ1]

None of those corrections would account for the hydraulic fluid blowing out the tank vent, guys.

THINK!

Ah another one I didn't see, I should read the whole thread but sometimes it just takes too much time! Ha ha. Time to call HL supply and get my new 592xpg! CJ

 

[ctf58]

Thank you all guys,
As far as me being a newbie, I guess that would be correct when it comes to working on hydraulics. But I have used splitters for years and have rebuilt car engines and am a retired master electrician. Oil venting seems to be fixed, I reconnected lines and found a high pressure line that did not seem to be sealing where it swivels. As far as plumbing the pump is mounted on the bottom of the vertical shaft engine with a re-enforced 2' long 1" hose from the bottom of the reservoir to the pump, pump to 3000psi pressure guage then on to "in" on valve, "out" on valve to inlet of reservoir located on the top of the tank. "A" Outlet port of Valve directly piped via nipple to ram end of cylinder. "B" Outlet port of Valve to end of cylinder farthest from ram end. I cannot change connections because of length of lines. I'll try to post some pics.
I do agree that the motor might be small, but you dance with the girl you got. Plus it can build 2000psi in one direction, just happens to be the wrong direction.

Thanks again guys

 

[ctf58]

Hopefully these post up.

 

[ctf58]

Pump, and valve

 

[James Sawyer]

My 2 cents I agree if the pump dead heads at a high pressure the motor will bog down and stop running that's a problem. All hydraulics system should have a bypass some where... on the pump and/ or the control valve, dead heading the hydraulic pump without a functioning bypass can be dangerous...something is going to break (line usually). The control valve should have what looks like a plug, inside that plug is a spring and steel ball this should be check valve (bypass). If this has a filter, it's should be between the tank and pump inlet, but I have seen system where the filters is on the return line to the tank which is wrong. So, if some sawdust got inside the hydraulic tank and filters is after the pump on the control valve return then it could have something lodged in the check valve.

If the pump is producing 2200 psi on any circuit then the pump is working ... there is nothing wrong with the pump.... its got be a problem in the bypass on the circuit not working. If this pump is a 2 stage there is adjustment screw on the pump to set the stepdown. Say the pump is 16 gallons/min on the primary stage, If the splitter motor bogs down at this high flow, it's go into the 2nd stage (usually 5 gal/min) so its easier on the motor. Lower flow less HP needed from the motor. The stepdown is set so the system pressure can remain high at the working pressure and not kill the motor. The over all pressure setting for the system bypass is for safety... these are separate adjustment from my experience.

Depending on you equipment the bypass adjustment can vary, I would look up the information on the pump and the control valve. Research these adjustment procedures. Note: the bypass pressure setting is not the adjustment for the step down on lower 2nd stage operation. If the pump stage step down is working you should hear the motor bogging, then speed up and the ram will move at slower rate... this step down adjustment is on the pump. The control valve should have bypass adjustment or it maybe factory set too I guess.

As other stated if the control valve on ram return side is 2200psi then there is problem at the control valve if all the plumbing is correct. So...that said you should have a line from the tank/reservoir to the pump inlet, The pump should have a output line to the control valve. The control valve should have lines to each side of the cylinder and return line back to the Tank/Reservoir. You don't need to swap lines, just visually check the plumbing is correct.

Your problem is in a control bypass is my guess.

 

[rancher2]

ctf58 Looking at your pictures you posted looks like the relief on the new valve is set at 2250 PSI. Your building 2200 on the gauge so the pump is building to the relief setting. Looks like you have a filter on the inlet to your pump if its not plugged up or the tank is low enough on oil that your are running out of oil on the extend cycle making the pump cavitate then that cylinder has to be bypassing on the extent cycle. Be it the piston is cracked or the seals are bad. I dislike tye rod cylinders. I have had a lot of issues with them on farm equipment. I myself never want one on a log splitter. You could also unhook the hyd hose to the extend side of the cylinder and put a pipe plug in it and put the valve in extend position with it running and see what the gauge reads should be the 2000 PSI.

 

[dave ensign]

Ok, you can't switch hoses which would have provided some insight. Not sure but it does sound like a bad cylinder that leaks (blows by the piston) more going forward and less on the return. I DO NOT think it has anything to do with the pump or the engine. Check you fluid level, hose connections and filter for the spitting issue

 

[dave ensign]

James,

You say the filter should be on the intake but post a diagram of it on the return? I favor the return but I do not have any great reason.

Dave

 

[user 74409]

Here is a suggestion you can try without spending any money. Remove hex shaped cover from low pressure relief valve on pump and turn screw found underneath cover counter-clockwise several turns to lower "kick-down" pressure between low and high volume. Current setting of 650 psi at 16 gallons per minute is too much for your engine and is causing your stalling problem. Next, go to directional valve and turn pressure relief screw counter-clockwise to lower pressure from 2,250 down to 1,800 psi (might be shiny screw in third photo but not sure). Try splitting a piece of wood and see if this solves your stalling problem (expect it to be slow). If it works you can use as is or upgrade to 8hp engine (pressure washers with failed pumps make good donors) or keep engine and go with 11 gpm pump.

Valve specs:
Specifications:
• Maximum GPM: 30
• Maximum operating pressure : 3,625 PSI
• Spool action is spring center/hydraulic kick-off
• Built-in relief valve preset at 2,250 PSI
• Kick-off pressure is non-adjustable, preset at 800 PSI


Pump specs:

• GPM: 16
• Shaft: 1/2in.
• Inlet: 1in.
• Outlet: 1/2in. NPT
• Dimensions: 7 1/4in. L with shaft, 5 5/8in. L without shaft, 3in. H across body, 3 3/8in. across mounting surface
• Minimum 8 HP or larger gas engine, direct drive only, horizontal shaft
• For use with open center hydraulic systems only
• First Stage: 16 GPM @ 650 PSI

• Second Stage: 3.5 GPM @ 2,500 PSI
• Maximum pressure: 3,000 PSI
• Bolt circle: 2.83in.
• 4 holes spaced 2in. on center
• Hole diameter: .344in.

 

[user 74409]

A few years ago I acquired a 20-ton version of this splitter from an estate with a water-logged Tecumseh engine and re-powered it with 190cc OHV Briggs engine. Before I sold it, I changed the filter set up away from the suction side to prevent pump captivation (caused by restricted flow and the death of many pumps).

 

[user 74409]

Looked at your photos again and have one more observation. The hydraulic oil reservoir needs to be vented and I could not tell from the pictures.. A small hole drilled in the "up-pipe" or oil fill cap be sufficient (not weatherproof) or a vented cap would be offer some filtration and would be better keep water out of the tank.

 

[pdqdl]

Thank you all guys,
As far as me being a newbie, I guess that would be correct when it comes to working on hydraulics. But I have used splitters for years and have rebuilt car engines and am a retired master electrician. Oil venting seems to be fixed, I reconnected lines and found a high pressure line that did not seem to be sealing where it swivels. As far as plumbing the pump is mounted on the bottom of the vertical shaft engine with a re-enforced 2' long 1" hose from the bottom of the reservoir to the pump, pump to 3000psi pressure guage then on to "in" on valve, "out" on valve to inlet of reservoir located on the top of the tank. "A" Outlet port of Valve directly piped via nipple to ram end of cylinder. "B" Outlet port of Valve to end of cylinder farthest from ram end. I cannot change connections because of length of lines. I'll try to post some pics.
I do agree that the motor might be small, but you dance with the girl you got. Plus it can build 2000psi in one direction, just happens to be the wrong direction.

Thanks again guys

In my experience, high pressure lines when loose always leak. Just sayin'.

You sure that's a high pressure line?

 

[CJ1]

Never filter a suction line on a open loop system. Always the return. A suction strainer 100 micron with a bypass on suction only. Cj

 

[ctf58]

Guys, thanks again for all your input. It is great to see so many willing to try to help.
I have found a local guy that does agro hydraulic work and he said he will take a look at it.
I have now had 2 different valves on it and adjusted the 1st one numerous times in both directions trying to find the sweet spot. I have left the brand new one as is for now.
On the pump, I have removed the cap and adjusted it in small increments counterclockwise until it does not stall or even slow the engine. All that does is reduce the forward pressure to about 450psi.
I put a brand new filter and even tool filter off completely and ran it.
No change whatsoever.
The splitter's detent does kick out at about 1500-1800psi. The only way for me to get the gauge to show 2000psi while retracting is to hold the level and fight the detent.

AGAIN THANK YOU ALL!
I will update with what this guy says since he can be hands-on with it.

 

[fishdrivel]

24x4 cylinder
16gpm pump 2 stage
160cc honda engine
Energy valve with detent
Haldex pump
Hi guys,
Bought this old splitter and it is not building much pressure . New cylinder and engine. I put a pressure guage on the inlet at the top of the cylinder and only get 500psi when running the ram all the way to the plate at the bottom of the splitter and the engine will stall after about 5 seconds. Same results in a peice of 10"oak. I moved the guage to the inlet of the hand valve, on the line from the pump and got the same reading. It acts as if it is not going into stage 2, BUT, when I retracted the ram the guage will spike to 2000psi if I hold the handle and not allow the detent to disengage the valve. I'm at a loss.. could the valve be mounted in reverse and if so can the handle and detent swap ends?
Thanks in advance.

Have you checked/ cleaned the filter (screen) on the intake? Usually in the tank/reservoir?

 

[Oletrapper]

My 2 cents I agree if the pump dead heads at a high pressure the motor will bog down and stop running that's a problem. All hydraulics system should have a bypass some where... on the pump and/ or the control valve, dead heading the hydraulic pump without a functioning bypass can be dangerous...something is going to break (line usually). The control valve should have what looks like a plug, inside that plug is a spring and steel ball this should be check valve (bypass). If this has a filter, it's should be between the tank and pump inlet, but I have seen system where the filters is on the return line to the tank which is wrong. So, if some sawdust got inside the hydraulic tank and filters is after the pump on the control valve return then it could have something lodged in the check valve.

If the pump is producing 2200 psi on any circuit then the pump is working ... there is nothing wrong with the pump.... its got be a problem in the bypass on the circuit not working. If this pump is a 2 stage there is adjustment screw on the pump to set the stepdown. Say the pump is 16 gallons/min on the primary stage, If the splitter motor bogs down at this high flow, it's go into the 2nd stage (usually 5 gal/min) so its easier on the motor. Lower flow less HP needed from the motor. The stepdown is set so the system pressure can remain high at the working pressure and not kill the motor. The over all pressure setting for the system bypass is for safety... these are separate adjustment from my experience.

Depending on you equipment the bypass adjustment can vary, I would look up the information on the pump and the control valve. Research these adjustment procedures. Note: the bypass pressure setting is not the adjustment for the step down on lower 2nd stage operation. If the pump stage step down is working you should hear the motor bogging, then speed up and the ram will move at slower rate... this step down adjustment is on the pump. The control valve should have bypass adjustment or it maybe factory set too I guess.

As other stated if the control valve on ram return side is 2200psi then there is problem at the control valve if all the plumbing is correct. So...that said you should have a line from the tank/reservoir to the pump inlet, The pump should have a output line to the control valve. The control valve should have lines to each side of the cylinder and return line back to the Tank/Reservoir. You don't need to swap lines, just visually check the plumbing is correct.

Your problem is in a control bypass is my guess.

View attachment 984060

Looks like the drawing above has the filter in the wrong place? OT

 

[CJ1]

Looks like the drawing above has the filter in the wrong place? OT

The schematic has the filter in the correct flow path. In the return line with the oil flow returning below the oil level. The only change I would make would be a drop tube to the other side of the tank [away from the suction] with a 45 degree cut on the end of it to help with vortexing. CJ

 

[muddstopper]

If this has a filter, it's should be between the tank and pump inlet, but I have seen system where the filters is on the return line to the tank which is wrong.

I disagree with this statement. Pretty much every piece of equipment I have ever seen has a return line filter. Most large equipment also has a suction side filter and really expensive and sensitive equipment even has inline high pressure filters to keep even the smallest of particles out of control valves that could cause sticking Looking at the diagrams of pump circuits, already posted, they also show a return filter. Granted the return filter is usually a 10micron, but I have seen 5 micron as well as 20 micron. We used to have a machine that used 2 micron filters. That machine was used to filter dextron fluid and would take the red out of the oil. Return line filter housings usually have a bypass built in that allows oil to bypass when return pressure exceed 250psi. The oil then returns to tank unfiltered. You want to know where those little pieces of rubber seals come from that are causing your reliefs and control valves to stick, well its because fluid is bypassing the return line filter. That is the reason it is always a good ideal to install a suction side filter between the tank and the pump. There is nothing inside a hyd tank that needs rubber seals so what ever is flowing thru your hyd system is either introduced to the tank when you have the cap off, or it is coming from parts breaking down in the cyl, reliefs or pump.

He is having a hyd mechanic look at the machine, it will be interesting to see what the guy finds. I will reserve my speculations on the what might's until I hear a better explanation. A new control valve should have solved the problem, but as has been said, I have seen many a new part that didn't live up to expectations out of the box. That goes for control valves as well as new hyd cylinders. The pump is building 2000psi in one directions so it should build the same pressure in the opposite direction. I will suspect the problem is not the pump. Of course it now seems the op has been messing with the relief built into the pump so all bets are off. If I was to speculate at this point I would check the control valve and make sure the spool is shifting all the way in both directions. I bought a new valve once where the detent ball has slipped pass the end of the spool and wouldnt allow the spool to shift all the way in one direction. The little ball was between the spool and the cap and acted as a positive stop.