Spit carbon canister

[Paul Nelson <aloder@websgi.icomnet.com>]

My 76 Spit exhaust is really, really rich. Deathly rich to be more
accurate. The book(Haynes)says if the carb is adjusted right then the
carbon canister is bad or blocked. The ZS 150 is not too far off, so
does anyone know a specific way to test the canister? Also can it be
serviced or must it be replaced? Also the hose coming from the run-on
control valve is plugged and the intake manifold part is crimped and
sealed. Many thanks in advance.
                Paul Nelson
                76 Spitfire 1500