Carter BBS 1 barrel Corroded

too much in town driving with short trips. The engine never heats up .
When was the last time you took the carb off & looked under it like this ? Lawrence

I drive 25 miles round trip every day, i do have this problem its really hard for my slant six to reach 180 degrees it only reaches about 170 i took it off last week do you think it has to do with my heat riser valve? it works though