2001 mercury 150 -just bought used--no water flows from tell tale pee hole until the thermostats open is this normal? there is no bypass?? motor will run for an hour ( thats as long as i have run it) with no problem .
68 - See if you have a 3/8" water hose that terminates at the top of the block. This is the recirculation hose. You can tee a pressure gauge hose into this.