Water pressure question
 

I have Imco Shorties on a 35' fountain. After the 1st run I had 60 psi of water pressure at wot. I bought the Merc bypass valves and am now running 30psi at wot. As I come in and out of the water it spikes up to 35 psi.

I was told to run around 20 psi at wot. What are you guys running for water pressure at wot? Is 35 psi to much? I don't want to start lifting head gaskets.

Thanks in advance
T.J.

Re: Water pressure question
 

Try a Globe Blue Impeller from www.Boatfix.com
It is of a softer more plyable material than stock. I ran one and never exceeded 25 psig at WOT. 7-8 psig at idle. This was on a Supercharged motor with crossover that has bypass. Before the Globe Blue, I had water pressure issues.
I am going to run the same setup on my new N/A 540. It is a good starting point. I will post results.

Re: Water pressure question
 

RLW,
Do you find that the blue impellers last longer than the black rubber ones? I would like to put these in the SeaRay and want something that will last. Thanks for posting the website for them.
Robert

Re: Water pressure question
 

Thanks for the input.

Re: Water pressure question
 

Stock 502 Mag MPI. 15-20 PSI WOT. 7-8 PSI Idle. Your pressure seems awful high! :eek:

Re: Water pressure question
 

Do you have a p/n for that impeller? I can't find it on the web site.

Re: Water pressure question
 

For the Globe Blue GRW2000 impeller, call Les Hall at BoatFix at
561-848-0193.
He could steer you in the right direction.
Good Luck!
Russ

Re: Water pressure question
 

I used a -10 pop off valve to keep the pressure at 18 at WOT. You can plumb it into the main water supply between the the oil cooler and the cross over. I never had any problems with temperature or head gaskets.

Re: Water pressure question
 

I am running a pair of HP500's with Bravo I's at idle I have 1 to 2 psi and at WOT I am in the 15psi range. Am I out of spec? I never have heating problems. Extended idle it is in the 150 range, and at WOT maybe in the 165 range.

Re: Water pressure question
 

Go Big,
When was the last time you looked at your impellers?
Those numbers seem low to me.
Russ