Western Snowplows Midweight Series, Руководство механика

Страница: 91 / 104

Lit. No. 48163, Rev. 00 March 15, 2016
91
INDIVIDUAL SOLENOID COIL TEST
1. Remove both wires from coil terminals.
2. Attach an ohmmeter across the coil terminals.
3. A reading that is not approximately 7 ohms
indicates coil is damaged and must be
replaced.
4. Attach an ohmmeter to one coil terminal and to
the steel washer at the end of the coil.
5. A reading that is not "open" indicates that
the coil has internal shorts and needs to be
replaced.
6. If both readings are OK (i.e., approximately
7 ohms across terminals and "open" between
terminal and washer), then the coil is good.
NOTE: A good coil will draw approximately
1.5 amps.
TROUBLESHOOTING
1. Remove the coils from the solenoid cartridge
valves and remove the cartridge valves from
the manifold. Look for visible contamination or
damaged seals.
2. Check for stuck spools with a plastic,
aluminum, or soft brass probe by pushing
on the spring-loaded internal spool from the
end of the valve. The spool should move
freely through its entire travel. Spool travel is
approximately 0.07".
NOTE: Using the probe to move the spool may
shear the contamination that was affecting
spool movement.
3. Bench test the cartridge valve by installing a
coil on the stem and applying 12V and ground.
Watch through the side ports for internal spool
travel.
4. If the cartridge valve spool is stuck or its
travel is restricted, replace the cartridge. If
the cartridge valve appears to be in good
condition, clean it with parts cleaning solvent
and dry with compressed air, being careful not
to damage the seals.
5. Check the spool travel again in case any
internal contaminants were dislodged during
cleaning. Re-oil the cartridge valve seals
and O-rings and reinstall the cartridge valve,
torquing to 10 ft-lb). Install the coils and torque
the retaining nuts to 4 ft-lb.
NOTE: If contamination is seen in more than
one component, it is reasonable to assume
that the entire system is contaminated. In order
to perform a proper repair, the entire hydraulic
unit, including hoses and cylinders, must be
disassembled and cleaned. The source of the
contamination must be located and repaired
before reassembly.
Apply 12V
and ground
to coil
Cartridge valve
identification
marked on hex
(SV08-XXXX)
Watch here
Probe here
SOLENOID CARTRIDGE VALVE INSPECTION