I received this combination brake valve from a customer who was looking for a rebuild kit for his 1997 Ford Mustang GT. It's marked with an F7ZC-2B091-BB engineering number.
The brass body is marked with a date code and the engineering number. It has also been marked with engravings to identify the brake lines, but those aren't "factory" so we'll ignore them. The date code on this valve is "6347", which translates to day 347 of 1996, or December 13, 1996. I disassembled it to see if it's rebuildable. Follow along as I tear it down! Tools needed:
Start by removing the rubber dust cap and the large plug using the 3/4" socket or box wrench. Note the o-ring seals on the plug and the red plastic cap. Both will need to be included in a rebuild kit. It might also be helpful to include a dust cap in a rebuild kit, but molded rubber parts like this can be expensive to reproduce.
Remove the spring and piston. The piston can be removed with needle-nose pliers. The spring found in these valves is resistant to corrosion and is reusable. The piston seal will need to be included in a rebuild kit.
Remove the piston seal and the o-ring from the red plastic cap.
Now remove the small plug at the end of the valve using the 1/2" socket or box wrench. Be careful as you remove it. The spring underneath the plug can cause it to pop off. Note the o-ring on the plug.
Remove the spring and piston. The piston can usually be extracted by tapping the open end of the valve firmly on your work bench. Remove the o-rings from the piston using your dental pick.
The spring found at this end of the valve is also resistant to corrosion and is reusable. The three o-ring seals will need to be included in a rebuild kit. Note that the o-ring removed from this plug is just slightly smaller than the o-ring removed from the red plastic cap.