Sometimes replacement O'rings can be deformed, cross-sectionally undersized in diameter or perhaps a very small nick in the rubber itself. My 2 cents.
I have lined the pump orifice with a .005'' shim, it seems to be working, together with the sealant ,went for a 100 mile run yesterday and it held tight...
STILL leaking...and its starting to piss me off a bit :Banghead: ...i took the carbon tank off tonight and put the OE back on until I can get it sorted out,i'm going to get it re-sealed and try a bigger O ring, has anyone used Caswell tank sealant and does anyone know if its suitable for CF tanks..and can anyone point me in the right direction for an oversized O ring?, not sure what spec the OE O ring is.
