O-rings #4 and #5:
To get to o-rings #4 and #5 you will have to remove the rod that goes through the body of the valve. Before you remove the lever arm from the rod index the end of the rod and the lever arm so you can put them back together in the same orientation they originally were. Then loosen the nut and remove the lever arm from the rod. With the lever arm off you can pull the rod out from the inside of the valve.
NOTE: Some of the early 123 leveling valves only have one o-ring instead of two. If this is the case on yours just replace the one and save the other.
O-rings #4 and #5 seal the lever arm to the body of the valve
Reassembly and installation:Installing the Cam and Lever Arm:
Proper placement of the cam and alignment with the lever arm is key for the valve to work right and sit level when unloaded. After replacing O-rings #4 & #5 put the rod for the cam and lever arm back into the valve. Put the cam onto the rod so it is lined up as in the diagram below. You'll also have to pay attention to which way the rod is rotated. You need to have the notch on the rod for the bolt on the lever arm in the right location. Once you have the cam on and the notch in the right place you can put the lever arm on, and use a 4mm diameter locking rod to assure that the lever arm is in the correct place. Now you're ready to put the halves of the valve back together.
Re-installing The Valve:
Once the valve is back together re-install it back into the car. Be careful when you thread the hydraulic lines from the accumulators back into the valve. The valve is aluminum and if you cross-thread your connections you will be looking for a new valve. Thread them in by hand and make sure they aren’t cross-threaded before you tighten them with a wrench. You will need to refill the suspension fluid reservoir. The system is self-bleeding so you won’t need to do any bleeding. Start the car and look for leaks. If there are no leaks shut the car down and have a large helper or two child size helpers sit in the back. Then start the car and watch to see if the rear end lifts up like it should.
I have reseal kits available. Contact me if you are interested. I am asking $10 for the first o-ring set and $5 for each additional set. This includes all the o-rings in the valve, a 4mm locking rod, and shipping.
There is a printer friendly PDF version of this DIY linked at the top of this thread.
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