Thanks so much for all that are trying to help me!
I tried some things tonight before I saw your suggestion
I disasembled the pump and found that it was completly dry no water the impeler looked fine a little bit of rubber dust in the pump but nothing broken..
I did put a water hose in the boat inlet to see if water was coming from boat inlet to water pump that was fine
So I thought maybe the pump need to be primed to be able to suck water to the engine so I put back the pump and bottom hose and filled it with water from the top and put back the hose. I started the engine and ran the boat slowly for some time the temperature stayed very low almost no movement to the gauge. So I tought my problem was solved the pump just needed to be primed. So I opened the throttle at about 3/4 and immediatly smoke began to come from the engine (rubber burn sent) and the temperature gauge went to 200 F .So I closed the throttle to idle but the engine temperature doesn't drop...
It looks like the strap is maybe slipping when engine rpm goes higher...so the pump stop or turn slowly but the pump is supposed to pump water again at idle speed and then cool down the engine?
After I stopped the engine and I touched the strap and it was not hot...but the pump was really hot....
Chris, if your talking about the screw that goes in the cam (so the cam screw) my pump is not on the right position...my screw is not on the engine side...
So if you are right my impeller flipped..... but the pump look symetric do you guys think that once the impeller is flipped it should suck water no matter how the pump is mounted ( if it's symmetric)..
Does someone know the model number of the pump strap? my boat is a 97 hydrodyne with efi PCM 351 gt-40 pro boss engine
Thanks so much!