Mark III H/L Cover Question

Hello, just wanted to say that I appreitiate your blog. It help me to maintain my newly aquired 1969 Mark III. My first question about the headlight covers, open slowly after the car has been shut off. I do know that there are “check valves” that help in keeping them closed, but can those check valves still be bought ? or is there something else I’m missing ?
Ron
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Ron
Problems with vacuum headlamp covers opening too quickly when the engine is turned off is very common. The check valves are a common problem but are no longer available from Ford. At the moment we are supplying only good used ones from our parts cars. We are however pursuing a source for new ones and we hope to have a product available sometime in the near future. These valves are not the only common failures for these systems. Look also for leaks anywhere that the vacuum lines are routed to such as H/L door vacuum motors, H/L switch, vacuum reservoir and any of the vacuum hoses. A service manual is an excellent tool for you to use in diagnosing any vacuum or electrical concerns. Just as a side note of interest is that when these cars were new Ford advised us that it was normal and acceptable for the doors to remain closed for 24 hours. With patience though longer periods are achievable. If we can further assist you with any of these parts or manuals at any time please call Chris directly and mention your post on our blog.
Sincerely
Bill