INSTALLATION & ADJUSTMENT
of
Exapta
7777
s UniForce
J
J
J
J
hydraulic downforce system
for
JD 1850, 1860, 1890 (3-section), 1895, 1990, 1690 air drills
(See different instructions for box drills, 5-section 1890s.)
Installing the cylinders:
1) Remove the big coil spring on each opener: Lower the openers until they’re touching the
ground or shop floor, then put circuit in float. Note: Only remove the first nut from OEM spring’s
rod (the second nut pre-loads the spring; no need to mess with it). Knock out roll-pin (roll-pin
punch provided). Coil spring & rod/clevis apparatus lift out.
2) The lower end of cylinder’s rod slides into the cast
bushing, and seat it with several whacks with a rubber mallet
on a solid surface (adding a drop of red Loctite may be
prudent; provided) (Note: turning the bushing on the rod by
hand often allows it to go easily; if the bushing won’t go into
position, use fine emory cloth to clean any paint that may
have gotten into the bushing’s hole).
3) Set the cy bushing into the large flat washer, then
into the hole in the cast opener (see photo A).
4) From the bottom side of opener casting, the notched plate
slides over the cylinder rod and its ears go forward over the
opener arm (see photo A).
Position
the angled ear of the
plate behind/below the nut on the boot attachment bolt.
Secure with a 3/4" flange locknut,
being sure the prongs on
the end of bushing mate into the notches of the plate as you
tighten
. Tighten nut sufficiently that the notched plate sucks
up tight against the lower end of bushing (Note: the bushing
is longer than the hole in the shank).
5) Insert pin into top yoke of cylinder, and secure with roll pin.
Installing the support brackets for header hoses:
1) Trays are positioned directly over the rank of
openers that they serve. Position the center trays at an
offset fore/aft so they aren’t directly in line with wing
trays (see photo B) (they need clearance when wings
fold). The center section trays are spliced on 40 & 42/43-ft models (also rear center tray on all
_______________________
U.S. Patents Pending.
Instr. revised 13 Dec. 2016.
Photo A
Photo C