15
Purging Uni-Directional Pump #’s 1551, 3218
Retraction Purge:
Full Purge:
The retraction side of the cylinders is the rst to be purged of air.
• Begin to purge the retraction side of the system by pushing the UP ARROW for each pair of jacks or by
pressing ALL RETRACT. The jacks may be run in pairs (front pair & rear pair).
• You will know when the retraction side of the hydraulic circuit is purged when the uid level in the
reservoir stops going down and the pump changes sound (bypass mode).
• Release the control panel button(s). Repeat this process for all jacks. Rell the reservoir to full.
Next, cycle the system by extending jacks to the ground manually, using the DOWN ARROWS on the
control panel.
Do not allow the jacks to lift the coach.
After all jacks are in contact with the ground, press ALL RETRACT to retract the jacks.
Next run the jacks in pairs (front pair & rear pair) to full extension. Monitor the uid level and all ttings
for leakage.
Retract the jacks by pressing ALL RETRACT. Recheck the reservoir and ll to full.
Note: the uid level in the reservoir is at maximum when all jacks are fully retracted and minimum
when jacks are fully extended. This full extension and retraction in pairs should be repeated 3-4
times.
If uid in reservoir appears to be aerated/foaming, allow the unit to rest until foam dissipates (approx.
10 minutes).
Allowing the air to dissipate through the reservoir and maintaining the reservoir uid level will get
things working faster.
The jacks are shipped in the fully retracted position. This procedure also outlines the steps taken if
the jacks need to be purged of air following repairs, etc.
Fill the reservoir with automatic transmission uid. (Multi-purpose or any of the Dexron uids)
If uid in reservoir appears to be aerated/foaming, allow the unit to rest until
foam dissipates (approx. 10 minutes).
Allowing the air to dissipate through the reservoir and maintaining the reservoir
uid level will get things working faster.
Note: the uid level in the reservoir is at maximum when all jacks are fully retracted and minimum when jacks
are fully extended. This full extension and retraction in pairs should be repeated 3-4 times.