It has been my experience that the only part needed is the spool and actuator O ring for the 3 and 5 port valves. If I can get into the garage sometime today I can provide those numbers.

Having said that I have gone both directions with respect to Norgren valves. I have used new ones and I have used valves I rebuilt. When using any valves, because of the PITA it is to find suspension system leaks I have gotten into the habit of bench testing them, new and rebuilt, before using them. I just made a little hose and fitting rig so I could put pressure to the valve, actuate it and verify it is leak free. My definition of leak free is zero bubbles.

I am now leaning away from rebuilding unless I have a lot of time on my hands. There are two issues with Norgrens as they age. First, as everyone knows the rubber parts such as the O rings on the spool and actuator begin to allow leaks. The second issue is if any moisture has gotten into the system the internal valve body surfaces can exhibit corrosion and leaks will occur regardless of the condition of the O rings. Admittedly any minor corrosion or pitting may not allow leaks, especially when the lubricant on the spools fills the microscopic voids, but leakage will again occur much sooner than with new valves.

A final concern is the screws holding the end caps are steel, and the valve body is aluminum and when the two are put together galvanic corrsion occurs and sometimes the screws will break resulting in the loss of the valve.

So I am now using the following to guide me. If I have time and want to play in the garage I will rebuild my Norgren valves. I will only rebuild valves that have no indication that moisture was ever present. I will never install any valve without bench testing it for leaks because once installed chasing leaks is a frustrating time consuming project.

As a final note, the valves we use on our coaches are standard off the shelf valves and Prevost has them given proprietary numbers for their purposes. If you wish to you can buy the valves from other than Prevost, but you must provide the generic description such as number of ports, type of actuator, fitting size, etc. to get what you need.