Hydraulic problem with 3 point hitch on Yanmar YM165D

[Bazman72]

Hi everyone. I am a newbie tractor owner and have minimal knowledge of hydraulics. I have a Yanmar YM165D with a 3 point hitch problem. The hitch will lift if there's no attachment (it's too weak to lift anything) but sinks back down immediately. I need to figure out the problem but it's hard to know where to start. Hydraulic fluid level looks fine and fluid seems OK (not dirty or bubbly). Does this indicate some kind of leak? I haven't seen any fluid around the area.

Is there a troubleshooting guide (online?)? Does anyone have any idea how I should start? Thanks!

 

[The Nitro]

Does it have some sort of tap you can turn off that stops the hydraulic oil to the linkage? If it does you could try raising the hitch up then turning off the tap and see if it still sags down. If it stays up then it might have something wrong in the valving but if it sags down there might be something wrong in the lift piston seals.

 

[Bazman72]

Thanks. I will try this tomorrow. I would still like to find a manual or troubleshooting guide so I can figure out how this system works. Does anyone know of one?

 

[Bazman72]

Well the hitch drops at the same speed whether the tap is off or on. Does this mean a leak in the lift cylinder seals?

 

[Gunny]

Probably the o-ring in the lift piston. You might want to read the thread in the Yanmar forum where someone else was going through the same problems you have. Not an expensive fix, just a lot of labor involved.

 

[Bazman72]

Thanks Gunny. I will do that. I downloaded the parts manual so hopefully that should help.