water pressure on 40 horse johnson

[Jcrain]

Not sure if this is the correct area or not but on my dash, I have a gauge that says "Pressure" and goes from 0 to about 15 psi. My 40 Johnson runs about "4". A friend has a similar boat with a 90 marinar and his runs about the same. Is this normal?

 

[OBJ]

Re: water pressure on 40 horse johnson

Couple things factor into the pressure Jcrain. What shape is the impeller in, how much corrosion is built up in the water passages that might impede water flow, even the speed of the boat will influence water pressure. <br /><br />Best way to get a good idea of what the "normal" water pressure is, is to replace the water pump impeller or better yet just install a whole new pump kit, check or just replace the t-stat and then take some reference readings at different throttle settings. Now you have a reference to go by as you operate the engine.

 

[Jcrain]

Re: water pressure on 40 horse johnson

Ok, When I was seeing the "4" it was with muffs and water hose. I took it out today and was pushin 13 psi.

 

[R.Johnson]

Re: water pressure on 40 horse johnson

That sound's closer to normal, but maybe a little low, you may want to take a look at that water pump.