Dinasour wood splitter

[jdsawmill]

I am new to the Arborist site. I just purchased a dinasour of a wood splitter, I knew it had some issues when I got it and could use a little help finding the problem. It has a kohlor k241 10 HP motor on it,Vickers v214 8w 1a 12 vane pump.it has a 4 inch piston 6 or 7 inch bore and about 6 foot stroke.The man I got it from uses it for years and one day busted a hydro hose and never could get it to work right again.on the split stroke it works fine but on the return stroke it bogs the motor down real bad smd sometimes kills it.

 

[motoman3b]

Sounds like a restriction somewhere..... maybe some gunk got in the valving causing a block or something internal with a hose

 

[jdsawmill]

Sounds like a restriction somewhere..... maybe some gunk got in the valving causing a block or something internal with a hose

I am doing some replumbing and going to put new hydro fluid it and pressure gauge this week.I'll post a pic of it when I figure out how.it is strong enough in split stroke that it will flex the six inch I beam on the main frame in croched or knotty wood and barely grunt.

 

[turnkey4099]

I am doing some replumbing and going to put new hydro fluid it and pressure gauge this week.I'll post a pic of it when I figure out how.it is strong enough in split stroke that it will flex the six inch I beam on the main frame in croched or knotty wood and barely grunt.

Check all the elbows and T's. I had much the same problem and found that one of the elbow fittingwas a restrictor. 3/4" pipe size but with just a tiny hole in it used to slow down actuator action.

That is a low probability but if he couldn't find the problem...

Harry K

 

[muddstopper]

Blowed hose, replaced and then problems started. I would guess that the problem is what casued the hose to burst in the first place. Let me guess, was it the return hose that bursted. Did he replace the hose with the same size as the one that burst. Just because the fittings are the same size, doesnt mean the hose size is the same. If the replacement hose is the same as the original, I might lean towards the cylinder bypassing internally allowing pressure on both sides of the piston. On the split stoke, their is enough power that the cylinder can extend, but on return you have more flow going back thru your valve body than the relief can handle, hence, the engine bogging and excessive pressure on the hoses. Just a guess on my part. To test the cylinder, remove both hoses and take a air hose to blow into one port of the cylinder. You will see the cylinder either extend or retract fully. If at the point of full retraction or extention you can hear or see air blowing out of the opposite fitting, then the cylinder is bypassing and time for a rebuild. Sometimes the bypassing is so bad that you can unhook the rod end of the cyliner and use your hands to push or pull the rod in and out of the barrel, even with the hoses still attached. This would be a sure sign of a bad cylinder.

 

[jdsawmill]

Done some replumbing and a new pressure gauge.it builds up about 1000 to 1500 psi on back stroke so I guess I can try to check the cylinder next

 

[jdsawmill]

I tried one more thing.the cylinder move at an OK speed in split stroke but it moves real quick in return even though it bogs the motor down. I left one hose on the cylinder and worked the valve and then swapped to the other hose and it did not boh the motor in either direction then just shot the hydro fluid across the yard no restrictions. I will try and get the fittings to test the cylinder with air and see what that tells me. This thing is very heavy duty appears to be 4" solid piston.

 

[homemade]

Pics or it didn't happen

 

[mga]

I am new to the Arborist site. I just purchased a dinasour of a wood splitter, I knew it had some issues when I got it and could use a little help finding the problem. It has a kohlor k241 10 HP motor on it,Vickers v214 8w 1a 12 vane pump.it has a 4 inch piston 6 or 7 inch bore and about 6 foot stroke.The man I got it from uses it for years and one day busted a hydro hose and never could get it to work right again.on the split stroke it works fine but on the return stroke it bogs the motor down real bad smd sometimes kills it.

just out of curiosity, what would you use a 6 foot stroke for?

 

[Homelite410]

just out of curiosity, what would you use a 6 foot stroke for?

That would be absolutely fantastic for making a split rail fence

 

[jdsawmill]

I has saw video of a wood splitter on YouTube of a splitter that you can put 3 sticks OK wood inline and push them threw a die type splitter and come out in six or eight pieces pretty cool. I do have pictures of this thing now but can't figure out how to post them on here.

 

[jdsawmill]

View attachment 314815

 

[motoman3b]

Looks to me like the return plumbing steel lines are awful small... also with a cylinder rod that huge its going to put strain on the return stroke as the area for oil to push it back is small

 

[big mog]

check the valve block for any bits of hose internal that might be blocking the return to tank orrifices in the block, these would restrict the flow and could be the problem

 

[muddstopper]

With that large of a rod, you are returning more oil to tank on return stroke than the pump is suppling to split with. Any restriction, be it a small fitting dia, hose, relief valve, ect, is going to cause excessive pressure build up and excessive heat. Double check all fittings and hoses, if a smaller hose was used to replace the one that blew, it could be causeing your problem. Relief valve could be sticking or the spool inside your control valve isnt shifting all the way giving the olil a clear path back to tank.

When you where trying to work the valve with one hose unhooked, was the cylinder fully retracted or extended the direction you where trying to move it. If it was and still blew oil across the yard, then your cylinder is bypassing. If the cylinder wasnt in full retract or extend and had room left to move when you operated the control valve, you where just emptying the cylinder of whatever oil was already between piston and port. Retract cylinder all the way in and then disconnect the hose at the base of the cylinder, operate valve as if to retract cylinder even further, and see if it still blows oil out of the cylinder port. .

 

[dave_dj1]

Sounds like the cylinder is bypassing internally. You may have to take the cylinder apart and rebuild it.

 

[origionalrebel]

there is a term for what you are describing with the huge rod dia. vs piston dia. i don't remember the term but what happens is it takes much less volume of oil to return the cylinder than it does to extend it. it will amplify the pressure in the extend side of the cylinder and can be extremely dangerous. the system must have a means of dumping all that volume of fluid contained in the extend end of the cyl. i'm sure if that old thing had been designed by someone in the know it would have some means of regulating the speed of the return stroke to prevent overpressure in the return circuit. spliteze uses a dump valve on some of their splitters to speed up the return stroke. i hope i haven't just muddied the water here. i didn't stay at a holiday inn express last night but i did read this in a hydraulic book some time ago.:msp_rolleyes:

 

[jdsawmill]

I unhooked both ends of the cylinder tonight and put air pressure on one end and left the other open and it did blow air out the other end then I swapped the air to the other end and it let air pass thew also.then I put a chain on the rod to keep it from fully contracting and then to keep it from fully extending and air still past out the fitting on the other end. So just as many on her suggested I think my cylinder needs rebuilt.

 

[homemade]

Looks like a cylinder from an excavator. I would recommend like everyone else has said, go to bigger hoses. I like going one size bigger then the smallest port for that specific hose... For instance, if the port on the cylinder is 3/4 and the valve has 1 in connection. Put the one inch hose on . a dump valve on the return stroke wouldn't be a bad thing either. I will allow you to, on the return stroke, put the oil straight into the reservoir instead of forcing threw the valve.

I've seen it on the bucket on a backhoe or track hoe. Designed to have power on the curl stroke but on the dump stroke they don't care about power but need the speed to empty the bucket faster.

 

[jdsawmill]

I like the idea of putting a dump valve on it and have a friend that i at can get some one inch joses from cheap.I may have to save my money to rebuild this cylinder don't know how much that will cost yet.