Western Snowplows Midweight Series, Mechanic'S Manual

Page: 21 / 104

Lit. No. 48163, Rev. 00 March 15, 2016
21
HYDRAULIC SYSTEM OVERVIEW
It is possible to remove cartridges and check
valves from a hydraulic unit without draining the
hydraulic fluid from the reservoir.
1. Install the Diagnostic Harness (PN 29290-1)
following the instructions included with the kit.
2. Cycle through the control functions twice to
remove pressure in the hydraulic unit.
3. Slowly remove the breather from the top of the
hydraulic unit.
4. Either (a) completely drain the reservoir and
skip to Step 9, or (b) proceed with the following
instructions for removing hydraulic components
without completely draining the reservoir.
5. Install a 3/8" barb fitting into the top of the
reservoir tank.
6. Attach a hand-operated vacuum pump to the
barb fitting.
7. Using the vacuum pump, pull a vacuum of
approximately 5"–10" Hg.
8. You should now be able to remove cartridges
and check valves from the hydraulic unit with
minimal fluid 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 fitting.
9. Reinstall the breather and remove the
Diagnostic Harness according to the
instructions included with the kit.
Excerpted from Gland Nut Ram Seal Kits Service Literature (Lit. No. 28944, Rev. 01).
CARTRIDGE AND CHECK VALVE REMOVAL