Cooling Problem- 6HP 2 cycle outboard 1992

My motor has a problem. No water comes out of the tube under the head when the engine is hot. I have visually checked all areas for water flow(intakes, and chamber where thermostat is), changed the impeller even though the old one looked functional, and changed the thermostat. I also took the thermostat out and blew air through the tube that water is supposed to come out of. I think that the internal cooling passages are blocked?? It had been run in salt water before I got it. I am trying to make it work properly. Any suggestions on how to verify this or check that they are clear, and how to clear them if they are plugged?
Thanks for any help.
Bill

[tunnels]

My motor has a problem. No water comes out of the tube under the head when the engine is hot. I have visually checked all areas for water flow(intakes, and chamber where thermostat is), changed the impeller even though the old one looked functional, and changed the thermostat. I also took the thermostat out and blew air through the tube that water is supposed to come out of. I think that the internal cooling passages are blocked?? It had been run in salt water before I got it. I am trying to make it work properly. Any suggestions on how to verify this or check that they are clear, and how to clear them if they are plugged?
Thanks for any help.
Bill

I have also asked the same sort of question about salt deposits and build up inside those small water passage ways . I have a 115 and just had the 2 heads off and a physical scrape out and blow through but would like to know about the stuff you cant see in those forgotten hard to get to places !

[boats.net]

Was the water pump housing melted? May need to replace it as well. If you know water pump is good then remove head and exhaust plates and clean passages, on a 6hp the engine is easy to remove and check upper water tube grommet.

The water pump was ok. I am going to take the power head off and check and clean that area. Thanks for the advice!

6HP Yamaha Cooling

The water pump was ok. I am going to take the power head off and check and clean that area. Thanks for the advice!

Cooling on 6 HP Outboard

It is working now. The tube was plugged that leads up from the pump. I was able to break that up. Unfortunatly I did a couple of things at once so I am not positive what really did it. (wires and air) Thank you for everyones input. I appreciate it!

Regards,
Bill