Any one know what is the recommended numbers on water pressure for 496HOs?. Ran my boat 3 weeks ago and saw that water pressure gauge on my port side is high than my starboard side after 2500 RPM. When running @ 4000 port side gauge constantly changing betwwen 22 to 27 and starboard shown steady @ 20. Any thing I can do to check?

Thanks

Blocks get crap in them,sand,mud,iron rust deposits from the block itself,this can cause a blockage and cause inaccurate readings.The 496 should have closed loop cooling but water still has to enter some where inorder to show pressure!Find the exit water line and back flush meaning were the water would exits the boat,put a garden hose there and flush everthing back out!

maybe impeller missing 1 of those fins???

I can't explain the difference in the two motors. But, even the 20 PSI doesn't seem out of line. At 4000 RPMs, I'm running less than 20 psi. From my Diacom scans, I'm showing a peak of about 23 psi, that's including WOT, 5000 rpms.

The raw water feed routing is different on the port side than the starboard side and the pressures will always run slightly different than each other. The pressure numbers you are seeing seem to be within the standard operating range and if you had any real issues like restricted flow and overheating the temperature sensors on each manifold would send an overtemp signal to the ECM and your Guardian system would beep and indicate a temperature fault condtion of exhaust water temperature high.

Ray @ Raylar

I've never tried to track down the lines and ports but my 01 496ho that has just turned 300 hrs has run over 35 lbs since it was new. It pegs the gauge after about 3500 rpms.