r65 mono upper fork leak

[dmsantam]

hi all, i have a 1985 r65 mono and the front forks leak from the top. I have the second version of the forks in the diagram attached. From the top, there is plastic fork cap (1), allen head bolt (2) with oring (3) into 36mm nutted fork cap (4), upper fork plate (not pictured), steel washer (5), fork stanchion (6). The leak appears to be coming from the interface between #5 and #6. Is the perfectly machined surfaces of these two items providing the seal? In my experience there has always been an oring on the fork cap (4), but that doesn't seem to be the case on this bike.

The top of the fork stanchion is not perfectly smooth, like somebody has hammered on it before, so that's maybe the issue here. Can I use something like thread sealant with PTFE on the upper few threads of #4? Interested in your thoughts, thanks.

 

[Skywagon]

If you don’t find an answer here, google Duane Ausherman. Not sure if he is still on line or not, but was very knowledgeable of airheads. Next ask Ted Porter. He rebuilt my airhead forks. 

[taylor1]

Snowbum BMW is another web site that is everything airhead. Sadly he passed away a few weeks age. As Skywagon mentioned, Duane and Snowbum both have excellent web sites that covers anything you could think of.

RIP Robert Fleischer