not sure about a 1968 but mine ( 1966) has one inside the hydraulic oil tank. your best bet is to obtain the parts book for your machine , available on e-bay an on the John-Deere site . Dig in boy !! J-D 350 straight 1966. model # = T4F3D. serial # = 08883T. J-D 690-B 1980. model # = D690B. serial # = 007364T.
This is the COMPLETE Technical Manual for the John Deere 850, 900HC, 950, 1050 Tractors. It contains profound data about looking after, gathering, dismantling, and adjusting your John Deere 850, 900HC, 950, 1050 Tractors. This manual contains data and information on this model. Has specs, charts, and genuine photograph representations, shading
Here's a selection of Hydraulic system information that you can view: 850-950-1050 Hydraulics. If the power steering is working fine and the rest of the hydraulics are weak then the flow divider may be the issue. It could be something as simple as a bit of debris sticking the valve.
Replace fuel filters every 400 hours. HYDRAULICS (OPEN CENTER) HYDRAULIC/MAIN ENGINE GEAR CASE FILTER AH128449 (S550, S660, S670, S680, S690) HYDRAULICS (CLOSED CENTER) (FILTER IN RESERVOIR) AXE12964 (S680, S690) AL203061 (S690) S. N (-745100) Filter change interval for all three filters is 400 hours. (Click here for capacity)
xm3Vg.