Operating Instructions, Form No. 102355, Back sheet 2 of 4
Bleeding Air From The System
Air can accumulate in the hydraulic system during the initial set-up or after prolonged use causing the cylinder to
respond slowly or in an unstable manner. To remove the air:
1. Open the filler plug two full turns.
2. Place the cylinder at a lower level than the pump.
3. Extend and retract the cylinder several times without putting a load on the system. Air will be released through the
pump reservoir.
IMPORTANT: Some spring return cylinders have a capacity in the rod that forms an air pocket. Bleed this
type of cylinder when positioned upside down or lying on its side with the port facing upward.
Hydraulic Fluid Level
1. Check the oil level in the reservoir after every 10 hours of use. The correct level of oil is 1/2" from the top the filler
plug hole with all cylinders retracted.
2. Drain, flush, and fill the reservoir with approved high-grade hydraulic oil after every 300 hours of use. The
frequency of oil changes will depend upon working conditions and the overall amount of use and maintenance
given the pump.
Draining And Flushing The Reservoir
The reservoir should be drained and flushed with a nonflammable flushing fluid after every 300 hours of use.
IMPORTANT: Clean the outside of the pump first to keep dirt from entering the reservoir.
1. Remove the four screws that fasten the pump assembly to the reservoir. Carefully remove the pump assembly
from the reservoir without damaging the gasket, filter, or safety valves.
2. Clean the inside of the reservoir, and fill it with a nonflammable flushing oil. Rinse the filter clean.
3. Place the pump assembly on the reservoir again, and secure it with two of the four screws assembled in opposite
corners of the pump housing.
4. Start the pump and let it idle for several minutes.
IMPORTANT: Run the pump with the valve in neutral, or run
the hose back to the reservoir. Do NOT build pressure.
5. Remove the pump assembly from the reservoir again. Drain and clean the reservoir.
6. Fill the reservoir to 1/2" from the top of the filler hole with an approved high-grade hydraulic oil.
7. Place the pump assembly (with gasket) on the reservoir. Assemble the four reservoir screws again and tighten
securely.
Adding Oil To The Reservoir
1. Retract the cylinder, and disconnect the power supply.
2. Clean the area around the filler plug. Remove the filler plug, and insert a clean funnel with a filter.
3. Fill with approved, high-grade hydraulic oil (215 SSU @ 100° F) to 1/2" from top of filler hole.
Checking Brushes on Universal Motors
To help prevent premature failure of the armature
the brushes should be checked periodically.
1. Remove the brush holder caps and brush assemblies.
2. Replace the brush assemblies if they are 1/4" long or less.
See Figure 7.
3. Install brush assemblies and brush holder caps.
Figure 6
Figure 7
Note: Shaded areas reflect last revision(s) made to this form.
7/8"
(new)
Replace when
1/8" lg. or less
Lubrication
To check the level of lubricant in the gear box:
1. Mark the motor housing parts for alignment during reassembly.
2. Remove the four machine screws holding the motor assembly to the pump housing.
See Figure 6. Lift the motor assembly away from the pump housing to uncover the
gear box.
3. If the largest driving gear is not completely covered by oil, add SAE 90 gear
lubricant.
4. Assemble the motor to the pump housing again, aligning the marks made in Step 1.
