Norgren Valve Rebuild & Replacement

After finishing the foam work around the entry steps, the next item on the list was the pair of Norgren solenoid valves. Our coach has two: the closer one controls the step well cover, and the farther one operates the entry dropdown step.

Both had been intermittently leaking, so I was hoping disassembly and cleaning might sort things out. I also wanted to improve the mounting, a Foretravel deserves better than a scrap of pressure-treated 2x2, and properly seal the butt splice connectors while I was in there.

Removing the Valves

Removal is fairly straightforward. The newer of the (2) valves (Norgren V61R517A-A312JB) was simply screwed into its wood block. The older original (P/N MK01CEA35AGNA) was mounted with a nut and bolt through the back of the step cavity, reaching it requires either a ten-foot wingspan or a handful of extensions.

On the bench, the older valve showed significant corrosion, and one of the mounting bolts wasn’t coming out without a serious fight. It wasn’t worth the effort, so I opted to replace it entirely.

The newer valve was in better shape, so I disassembled and cleaned it. A word of caution during teardown: several components are spring-loaded, and it’s very easy to send parts across the room. There are a few replaceable O-rings, and the valve uses a seat/piston design similar to HWH valves, including the typical wear ring indentation. After reassembly, it seemed to operate as expected.

Parts & Sourcing

A replacement Norgren valve runs about $125 plus tax and shipping from most vendors. As an alternative, some have had success with a much cheaper option, the TAILONZ PNEUMATIC ¼” NPT Solenoid Valve, DC 12V at around $17. I picked up two of those and kept the rebuilt Norgren as a spare.

For the exhaust speed restrictors, I went with Arrow Pneumatics ASP-1SCH, the same brand used in the original setup.

Heat Testing

Before committing to the Tailonz valves, I ran a comparison heat test, powering both the old Norgren and the new Tailonz to see how warm each would get under load.

• Norgren, rated ~2W, topped out around 105°F
• Tailonz, rated ~4W, ran noticeably warmer at ~150°F

The Tailonz heat was worth addressing, so I added a small heat sink to the face of the valve and re-ran the test. With the heatsink it settled into the 105–110°F range, a solid improvement, and comparable to the original Norgren. Both valves will be deployed with heat sinks and monitored over time.

Reinstall

The valves are now mounted, plumbed, and wired. The new aluminum mounting brackets have hole patterns sized to accept either valve style, so swapping in the spare Norgren later won’t require any modifications.

Deutsch-style connectors on the wiring mean a future valve swap will be a clean disconnect rather than another round of butt connectors. A few new 1/4” air lines were run where needed so mounting locations weren’t constrained by the original plumbing.

Air leak testing and final exhaust limiter adjustment were completed, the arrow valves really make fine-tuning the open and close rates an easy task.