Petcock oring

[chuck hahn]

Just curious. Has anyone measured the ID and OD of the oring on the vacuum plunger on a petcock??

I ask because i cleaned the seat for the oring with some steel wool, replaced the lever gaskets and as of now it doesnt leak but at some point i expect the diapram oring to start leaking. If anyone knows the size of that oring i would look at some sources to see if i can order some.
My other consideration is to place a blocker in place of the spring that will pernanently close it off and just use the PRI position when riding and shove lever down to the ON position when not riding. Basically making it a manual operation petcock and just be done with vacuum operations

[Rijko]

i remember a thread on GSR about that, or maybe in one of the writeups on Brian his site, can't find it now though.
IIRC it had the size listed, and also the tip that aftermarket plungers were approx. .5 mm shorter which could be overcome by a slightly larger o-ring.