Tweet
I have a 2004 225 hpdi that has only 11 to 15 psi at wot. It did have around 20 until about 2 months ago. I have changed the thermostats.popit valve, and water pump with no help. Dealers around say that only 11 psi is needed at wot. Any comments or advice?
-
-
During the hot summer months when the water is warm you may see only 12-15 psi of water pressure. The surface water temperature is warm already, therefor the thermostats have to open up sooner and wider (less flow restriction...) to allow more water through the powerhead for cooling, than during cold winter months when the surface water temp is 50-70 degrees. During the cold water months the thermostats stay closed longer and only open a small amount (greater flow restriction....) trying to keep the motor in the desired temp range, so you end up seeing more water pressure on your WP gauge as a result. This is normal. That is why Yamaha is saying 11 psi is sufficient for cooling, as long as there is sufficient water volume going through the powerhead.
Mike........ Miami, FL
Comment