1966 Mercury 3.9 Telltale

[kevinjgould]

How can I tell if the water pump is working on my 1966 Mercury 3.9? I see video's of a "telltale" outlet under the left side of the powerhead, but I can't locate it on my motor. Am I missing something? Thanks for your help

 

[tpenfield]

Looks like it is on the port side just below the lower cowl.