940 series Powerig®
(HK496)
Alcoa Fastening Systems & Rings
8
M
aIntenanCe
PARTS LIST
See Figures 3-6 for part numbers.
WIRING
See Figure 6 for wiring diagram and
TABLE 1
for wire
list.
PREVENTIVE MAINTENANCE
An effective preventive maintenance program includes
scheduled inspections to detect and correct minor
troubles. Perform the following steps monthly during
normal use:
Inspect hydraulic and electrical fittings to be sure they
are secure.
Inspect hoses for signs of damage. Replace hoses if
abrasion is deeper than the surface texture.
Rotate hoses end-for-end to equalize wear and
fatigue.
Inspect during operation to detect any abnormal heat-
ing, vibration or leakage.
Inspect hydraulic fluid. If contamination (particles,
water, sludge, etc.) is detected, clean the reservoir and
replace fluid.
Clean exterior surfaces.
Check supply voltage. Do not operate the the
POWERIG
®
Hydraulic Unit if the line voltage is more
than 5 percent above or below 115 Volts.
SPARE PARTS
The quantity of spare parts that should be kept on
hand varies with the application and number of the
POWERIG Hydraulic Units in service. For directional
valve and pilot valve maintenance, Seal Kit, 124100,
should be kept on hand at all times. This kit contains
O-rings and back-up rings required to service one
directional valve and one pilot valve. Other parts that
should be available to the service technician are:
Pump to Motor Coupling, Relay, Transformer, Pilot
Valve, and Motor Brushes.
DIRECTIONAL VALVE OVERHAUL
If minor overhaul of the directional valve (cleaning and
replacing O-rings and back-up rings) is necessary,
Seal Kit, 124100, is available. If major overhaul is
necessary, return the directional valve to the nearest
repair facility shown on the inside of the back cover.
Clean components in mineral spirits. Smear
LUBRIPLATE 130AA, or equivalent, on O-rings and
mating surfaces to aid assembly and prevent damage
to O-rings. LUBRIPLATE is trademarked and manu-
factured by Fiske Brothers Refining Co. and is avail
-
able in most localities. A handy tube of LUBRIPLATE
130AA is available from Huck as part number 502723.
INTERNAL ADJUSTMENT OF PRESSURE SWITCH
1. Remove the top cover of the switch.
2. Loosen two screws located in the bottom of the
switch housing.
3. Place a 0.20-inch-thick shim between the spring
retainer and the platen.
4. Loosen the set screw on the spring retainer until it
contacts shim.
5. Lock the spring retainer in place with the set
screw.
6. Slide the switch mounting bracket toward the
switch button until it contacts the platen surface.
7. Secure with two screws located in the middle of
the bottom cover.
8. Connect a volt/ohm meter to the electrical cord.
9. Tighten the switch adjustment screw against the
switch mounting bracket until the switch button
contacts the platen and actuates. The volt/ohm
meter will react when the button actuates. A click
can be heard.
10. Continue tightening the switch adjustment screw
1/8 of a turn after the switch button actuates.
11. Replace the top cover of the switch.
REPLACING PUMP TO MOTOR COUPLING
The pump to motor coupling can be replaced
by removing four socket cap screws holding
the motor housing to the cover plate and lifting the
motor to one side. Lift out the original coupling with
needle-nose pliers. Drop in the new coupling, align the
slots and reassemble motor to cover plate.
PUMP OVERHAUL
If pump requires overhaul return it, or the complete
unit, to the nearest repair facility shown on the inside
of the hack cover.
