I have an 05 pro xs, one of the first ones. At wot I only have 12 psi on my water pressure gauge. I've had a water pump, poppet valve, and lower unit flushed any ideas on what could be causing such a low water pressure reading. Idle is 3-5 pds

you might have it to high on the jack plate. if not then i would check the black grommet on top of the water pump housing. if it comes up a little bit it will cause this. Put a drop a super glue on one side of it and slide it back down.

I have a hydraulic jack plate, if I lower it down it reads the same. Is it on the outside of the lower unit?

No you will have to drop the lower unit. There should be a rubber grommet that sits on top of the waterpump housing.

Looks like I have the same motor as you. Could it be the gauge?

It could be but unlikely. Dropping the lower unit is not that hard and you dont have to take it all the way off to look at that grommet.

I run pretty high on the jackplate but im still around 16-18 psi at WOT. I will sit about 10-12 if im just running easy at about 5000 rpm

Mine only turns 5500

What rpm do u run at wot?

My rev limiter is set at 5850. But im running 1.62 gears in mine. Which in turn lets me have a great top-end and awesome gas mileage. Your motor should redline at 6450 if its an 2005. You are not turning enough rpm to achieve WOT. You have to start over with your set-up. Prop and jackplat height

Jones I do`nt think you have a problem ddantidwells is the same at same rpm.

Yes mine is the same psi at the same rpm but he is saying that is his WOT. Something else is wrong if he is only achieving 5500 WOT on a motor that can turn 6400.

your water pressure is fine.
i do agree you need to gain some rpms.


btw. those motors stop making power at 5950-6100

i propped my old 250 XS to run 6k any more rpms with a smaller pitch didn't work. tried everything.

29p prop at 6k rpms and 1.62's went 92.4 (bullet) and i had 22 lbs water pressure at 1.5" above pad.

Steve, u suggest I get a prop worked?