PatrickM

The plane is going to be at the shop for another few weeks - and the shop is 60 miles away... We had a lower seal blow on a newer mag, and the supplier is rebuilding it - was a bit out of warranty, so I should find out who it is, and give them a shout out. Does anyone have a 431-9 disassembled that can mic the length, diameter, and location of the o-ring groove?

wow - I thought that was only for experimental! Great - let me know! think that would be the route of least resistance.

let me see if I can get a set of calipers on mine!

Hi Everyone, First post. I've gone through the fuel cap threads, and they were very helpful. Looks like sourcing a replacement cap is my best choice, but this seems unique. The cap has the R added post casting. Does this mean the cap was modified post installation? Post production? On initial assembly? Just noticed @OSUAV8TER has one in his pic.... Reason being is the center post has pitted to the point that it lets water by the O ring (don't look at the one in the pic, it was new a year ago) The question being, can I grab an 431-9 and combine the caps to make a 431-9R ? Does anyone have a clean post? (just checking) My buddy is a metal whisperer, and i'd love to hand him the $$ to make a new post, but airplane. Our 1977 M20C has the stainless mating surface for the cap, that looks clean. Anyone have an interesting 3D print file for covers? Thanks, Pat