John deere 300 hydros

[Dconk91]

I have a jd 300 with front loader, and box blade, everytime i use to box blade my hydraulics die, but if i take the box blade off i have no issues, i was thinking that my 3 point hitch lift is leaking around the piston in the rockshaft housing, is there a better was to diagnose this?

 

[Tx Jim]

With hyd oil at operating temp,3 pt raised,engine running look in hyd filler hole behind seat for moving/spraying oil. If moving oil is seen then rockshaft valve seals are probably leaking & need replaced.

 

[Dconk91]

It was was settled debri behing the pump screen, a little help with a bore scope, and magnet and everything works great now

 

[Dconk91]

This is the hole

 

[Dconk91]

This is what my 300s trans looks like, it has 3 bolt holes for pressure control valve but does not have the second hole....

 

[Tx Jim]

Yes your tractor must be below serial number 45199. You can get by without installing pressure control valve or install valve & see what happens. Either way won't cause 3 to operate correctly