Engine water Pressure

Bmaggiac

I have a 2008 Rinker 330 EC with 350 mag mpi and bravo 3 sterndrives.
I got an alarm with vesselview saying "engine power limited" with "11' in the top right corner. I was told this is a water pressure issue. Check the water pressure and at idle (600 rpm) the water pressure was 8.8 port and 0.8 starboard. I swapped the sensors and the higher pressure moved to the starboard from port. This to me seemed to be a bad sensor so I replaced both sensors. I tested the engines at idle and the pressure is 18.0 port and 20.2 starboard. They both seem consistent with each other. Does anyone know if this is okay?

YYZRC

Mine read 1psi at idle and 8psi at 4000+ rpm. Impellers are new this year and have around 50 hours on them this season. 

Pat310

Did you buy OEM or Chinese knock offs?  I tried the cheap ones and one read zero all the time and the other read 40psi even with the engine not running. LOL. Paid the extra and put in OEMs. Lesson learned

Bmaggiac

Thanks for the feedback! I guess I'm going to buy OEM now. LOL

YYZRC

Agreed with @Pat310 - I also tried non-OEM at one point and they didn’t work. I was able to blow out the sensor with compressed air and got it working again. 

Spyderweb

@Bmaggiac, I have same boat and engines as you.  Monday, at idle in gear I got 12 and 10 psi, around 3850 rpm, I got 20 and 18.  New water pumps (and impellers) on their 2nd season, about 40 hours.  @YYZRC, are your numbers some kind of metric number?

YYZRC

@Spyderweb PSI same as you. Maybe my pump housings are scored enough to show reduced pressure - not sure. 

LaRea

I thought normal is more like under 3 psi at idle and 15-25 at cruise speeds.  All you're doing is pushing water through the tubes of the heat exchanger, and it shouldn't be that hard.  There would have to be some kind of restriction downstream of the pump to make more than 3 psi at idle.  

YYZRC

I guess I should clarify that my engines are raw water cooled (not Horizon/no heat exchanger). 

Spyderweb

Mine are also fresh water cooled.

Bmaggiac

Thanks guys! I took the sensors out and they seemed clean. I still decided to poke around the inside of the sensor housing with an awl. I re-installed the sensors. Now they read .9 and 1.4 at idle. Thanks for the assistance!!