Where is the hydraulic relief valve located on a Yanmar YM1500

[wireman1957]

Hi can anyone tell me where the hydraulic relief valve located on a Yanmar YM1500
i think it might be on the drop valve body near the control valve but not sure.
i think mine is bad as i have a weak lift and wont lift over 200lbs and the control valve squeals when lifting implements.
i changed the hydraulic/trans fluid and cleaned the screen and made sure the drop valve is all the way open and its still weak.
one thing i noticed is if i have a heavy implement on there it will just lift if off the ground slightly but if i move my the lift lever at about the mid way point back and forth real fast it slowly lifts the implement all the way and will stay up.
is this the control valve causing this or the relief valve ?
any tips would be apreciated.
you can email me at wireman1957@bellsouth.net if you can
Dave!

 

[J_J]

Have you installed a hyd gage to check pressure?

The relief valve is probably located close to the IN port on the loader valve.

Install a hyd gage in a tee in the IN port and max out the lift cyl and read the pressure.

Can you show several pics of your FEL valve?

 

[wireman1957]

Hi my tractor doesnt have a front end loader i only have a rear 3 point lift.
i havent put a pressure gauge on it to test it as i cant seem to find one locally
if you crack the hyd line it seems to have good pressure.
from what i read if the 3 point lift hydraulic control which is under my seat squeals its most likely a bad control valve , relief valve or its plugged up there in the valve somewhere.
the reason i think its the control valve is it lifts regular implements fine but when i use my dirt scoop with a little dirt in it or my 4 ft bush hog it doesnt want to puck them up .
but if i try lifting it and putting the lift control about the mid point or above and i work the lift lever back and forth fast it will pick it up all the way.
i think if it was a bad pump it wouldnt pick it up period.
im not hydraulic mechanic so im not sure if im right.

Dave!

 

[normde2001]

Forget the relief valve. It could as easily be any 1 of the valves shown in the Hoye picture.

 

[wireman1957]

yea i think i might take it all down and clean it and put new o-rings and seals in the relief valve , control valve and the hydraulic piston
i was just wondering where the relief valves is located on the lift system under the seat

Dave!

 

[winston1]

The assembly behind plug #39. Yanmar Tractor Parts: HYDRAULIC_LIFT

 

[wireman1957]

Thanks i apreciate the info
i was thinking that it was located there but wasnt 100% sure
i ordered O rings , seals , springs ect for the whole lift assembly including the control valve , drop valve , relief valve and lift piston and will clean and re Oring it this week hoping it cures my lift issue .
again thanks for the confirmation on the relief valves location