What is the proper way to use a hose attached flusher on my 2000 Merc
90hp 2 cycle? I am paranoid about putting too much pressure into it.
Consequently, the last time I tried to use it the motor overheated,
not nice. Should water come out of the telltale right away or does
the motor need to heat up first. Is there Any other way to determine
the right pressure so nothing is blown up and it doesn't overheat
either.

tks
Don
WA5NGP