Yamaha 1999 100 HP 4 Stroke

I have a (1999 manufactured date) 2000 100 hp four stroke.

I recently noticed no water pressure at the water pressure guage so I began to take it apart. I have water pressure coming out the peehole with normal pressure as usual.

I proceeded to troubleshoot running water pressure at each step with normal pressure coming from the peehole (output nipple) the whole time.
1. Took it apart at the gauge, ran engine with water on intakes no water
2. Took off water line to water gauge at motor no water (removed water tubing to brass nut)
3. Removed brass nut from engine (no water)

I'm now faced with a question of what to do next, can anybody advise.

Thank you
Alan

[boats.net]

Probably needs new water pump, thermostats and pressure control valve.

Yamaha 1999 100 HP 4 Stroke

Do you think it could be the water pump with a full "pee stream" but no stream at all to the water gauge area?

[boats.net]

Yes the water pump is always the best place to start.

try poking a hanger or other long sharp instrument ito the hole. It can get clogged from salt. Your water pump is functioning properly if you have a strong stream out of your "pee" hole