JB Weld
was reliably "gasoline proof" up until the addition of ethanol became common. Regarding it's ability to degrade various epoxies,
synthetic rubbers, and even some alkylid-based polymers, ethanol is just as nasty as methanol.
We use Miller-Stephenson's MS-904 (based on Shell Petroleum's "Epon" resin) for sealing applications that require that sort of strength, cured hardness, and chemical resistance.