Lit. No. 30118, Rev. 00
June 15, 2020
20
1. Lower the blade to the ground before making
any adjustment.
2. Remove the hydraulic unit cover.
3. The quill in the valve manifold adjusts the
blade drop speed. Turn the quill IN (clockwise)
to decrease drop speed. Turn the quill OUT
(counterclockwise) to increase drop speed.
4. Stand 8 feet clear of the blade when checking
the drop speed adjustment.
5. Replace the hydraulic unit cover.
CARTRIDGE & CHECK VALVE REMOVAL
BLADE DROP SPEED ADJUSTMENT
HYDRAULIC SYSTEM
It is possible to remove cartridges and check
valves from a hydraulic unit without draining the
hydraulic
fl
uid from the reservoir.
1. Install the Diagnostic Harness (PN 29290-2)
following the instructions included with the kit.
2. Cycle through the control functions twice to
remove the pressure in the hydraulic unit.
3. Slowly remove the breather from the top of the
hydraulic unit.
4.
To remove cartridges or check valves
without draining the reservoir,
proceed with
Steps 5–8 and 10.
To drain the reservoir before replacing
components,
remove the drain plug and
completely drain the reservoir. Reinstall the
drain plug. Replace the desired components
and skip to Step 9.
5. Install a 3/8" barb
fi
tting into the top of the
reservoir tank.
6. Attach a hand-operated vacuum pump to the
barb
fi
tting.
7. Using the vacuum pump, pull a vacuum of
approximately 5 to 10 Hg.
WARNING
Keep 8' clear of the blade when it is being
raised, lowered, or angled. Do not stand
between vehicle and blade or within 8 feet
of a moving blade. If the blade hits or drops
on you, you could be seriously injured.
Quill
8. You should now be able to remove cartridges
and check valves from the hydraulic unit with
minimal
fl
uid loss. Maintain the vacuum until
the replacement cartridge/check valve has
been installed. Once the replacement part
has been installed, release the vacuum and
remove the 3/8" barb
fi
tting.
9.
If the reservoir was completely drained
at
Step 4 above, re
fi
ll the reservoir with hydraulic
fl
uid to 1-1/2" to 2" from the top.
10. Reinstall the breather and remove the
29290-2 Diagnostic Harness according to the
instructions included with the harness kit.
