50hp johnson

[johnnyhihat]

i have a question. i have my motor at a marina getting worked on and the question is they have the lower unit off the motor to change the impellor and went to test the water supply to the motor by putting a garden hose on the copper water pipe that runs up the mid section to the power head they are trying tell me that motor is blocked with corrsion because there too pressure. isnt it true that with a thermostat in the head the water is not going to go through the head unless the motor is runing and warmed up. the motor is a 1973 johnson 50hp. i just put a new thermostat and gasket in a month ago and water passage around the piston was cleared.