How much water presure do I need

[alan griffiths]

I am runing a 70 merc with a 22p choper and I just tryed
to jack it up higher to get 60mph. but my water presure
is droping from 15psi to 5-6 psi will this damage my motor
or is this still enough to keep runing.

[Jay Smith]

I like no less than 15 lbs at WOT ! But robbing a motor from coolant will eventually cause it to seeze ......

[alan griffiths]

Thanks mate, I will drop it back down until I get a low
water pick up.