Flush and refill Leveler hydraulic system

The hydraulic jack leveler system on our Southwind is an older Power Gear manual system. I’m not sure if the levelers have ever been flushed in the 18 years since they were new,  so the only way to make sure,  flush them and refill.

The leveler pump / tank assembly is located just behind the front right wheel. Its fairly easy to get to and see everything. If you’re not sure where your pump is,  get someone to extend the jacks, while you listen and find out where the pump noise is coming from.  ED NOTE – Pump Noise:  The pump should sound like a high pitch whining sound.  If it sounds like a bunch of marbles in a food blender, raspy grinding noise,  you may have a pump motor going bad.  READ HERE.

Before I drained the system,  I worked on a problem with the two rear jacks.  They were backwards on the control panel.  Not a problem,  I simply reversed the solenoid valve connectors so the left button now works the left jack and the right button works the right jack.

Verify the jacks are fully retracted. I opened the drain on the bottom of the reservoir and drained about 2 gallons of fluid.  I don’t think it was Dex III,  It had a red color with a slight brownish / purple color and seemed more oily than transmission fluid.  I suspect it was regular ole hydraulic jack oil.  Not a problem that would work fine. Almost anything will work,  If I still had access to aircraft 5606,  I would have used it.  The fluid I drained out looked clean and I didn’t see any contamination.

The filler port on my tank is up high and no way to get a funnel up there.  To fill the tank, I used a small hand pump I purchased from Harbor Freight ($7.00).  I used just a little less than 2 gallons of Valvoline ATF DEX III Synthetic, pumping it into the tank until it just started to overflow out the filler port.  (Walmart has this fluid, $18 a gallon. Its the same fluid I use in the 4R100 transmission and also the power steering system.)

I put the cap back on the tank and cycled the jacks a couple times.  I’d extend them all the way out,  let them sit for a few minutes to allow any air to float to the top of the cylinder,  then retract them.  I did this a couple times, topping off the tank after each retract.  After two or three times,  you won’t need to add any more fluid.

The only problem I observed,  The left front jack (500384) leaked when it was fully extended and the pump was running.  I’ll grease the fittings on the jacks,  and keep an eye on the jack,  perhaps start looking for another jack or new o-tings.

ED NOTE – Followup – The jack piston was broken internally.  CLICK HERE to read the tear-down report