wood splitter sudden loss of pressure

[jonsstihl]

well, I couldn't get one of the hydraulic lines off but then I realized, I don't need to take the line off so I kept going. gland cap came off easy after my homemade tool took a crack at it.

piston came off easy after putting the rod back on the splitter.

problem is. I didn't see any damage severe enough to be the cause of the problem. I will rebuild it anyways if I can find the parts. the piston seal is just an o-ring with two support rings beside it Plastic or rubber.

I think I may be looking at an internal valve failure because it isn't leaking externally.

this valve is particular. anyone know of a log splitter valve that springs to a work port instead of to neutral and I don't need the detent in the retract position or the auto release from detent. I will post pics after I call the dealer.

 

[jonsstihl]

here are a few pictures

the tool isn't pretty but it works. I put it all back together as is to test just the cylinder and it holds 2400 psi of pressure so next step is disassembly of the valve.

 

[davedj1]

Looks kind of worn to me. Also you will find an O-ring on the inside of that piston or even a gland depending on it's design.

 

[jonsstihl]

I took the gland and the piston off before, those were just the best pictures. the seals don't look new but they are not broken or cracked. Are you talking about the piston that looks worn. everything looked good and those marks just seemed like small witness marks that don't catch a fingernail.

o-ring between the piston and rod was intact, the gland has the same type of setup as the piston one o-ring plus back up ring in the groove only it has an extra nylon(hard palstic) wiper seal.

 

[jonsstihl]

took apart the valve yesterday cleaned everything out and re-assembled. now it works. I found a small piece of metal that appears to be from the relief valve seat. The edge of the slot seems to have broken off but the damage was not in the sealing area so I cleaned it out real good and re-assembled and it is back to normal.

should have checked the simple stuff first but I'm glad I took apart the cylinder. learned a lot and I definitely would not be afraid to tackle a loader cylinder rebuild.