Prior to working on the leveling system:
- Verify the jacks are completely retracted.
- Open all the manual retract valves to ensure there is no pressure in that cavity.
- While the retract valve (poppet) and extend valves (spool) look the same when installed, they are completely different in design and operation.
- Both types of valves are susceptible to damage from foreign objects/debris and over-torque.
Before the retract or spool valve stems can be removed:
The appropriate electric coil must be removed:
- Two styles of coils are in use.
- The first style is comprised of an electric coil, metal cover, and metal base for the cover.
- The second style is a single piece unit with the metal cover and the base molded into the electric coil.
- In either style, a 3/8 inch nut is used to hold the coil on the retract or extend stem.
- The nuts are initially installed using Loctite.
- Remove the 3/8" nut, and 12 volt coil assembly. This will expose the hydraulic stem for cleaning and removal.
Removal of the stem/valve:
- Cleaning the area prior to removal is important to keep dirt and foreign objects out of the hydraulic unit.
- Use penetrating fluid, and a brush to clean the area around the the valve.
- Once clean, then use compressed air to remove remaining debris prior to removal.
- Use a deep socket to remove the stem from the manifold. There will be no pressure, so only drops of fluid will be lost. Before installing a stem valve clean the seal surface on the manifold.
Installation of the stem/valve:
- Lubricate the o-ring on the valve with Dexron ATF prior to installation.
- When installing the stem do not use more than 144 inch pounds of torque. Since the stem is sealed with the o-ring, extra torque will serve no purpose and could damage the threads on the aluminum manifold.
Install the coil on the stem:
- Slide the coil on the stem, and install the retaining nut with Loctite. Tighten the nut to 36 inch pounds. Again it is important not to over-tighten. Over-tightening this retaining nut can distort the stem valve and cause it to not function properly.