If you are getting that much pressure at an idle, your tube is fine. I would look at the thermostats for restrictions. Pull them out and run motor to see if tell tale picks up. If you run in salt water the cowling fitting necks down and salt builds up.
I run a hose from each thermostat cover thru the cowling. No fittings. Just the 5/16" hose sticking out. That way I can see that both sides are flowing. The stream cycles from weak to strong as the 'stats open and close while idling. I swap out the right fitting for a spare left one so only one barb per cover. You can just cap the extra barb and zip tie if you go this route.
This is the best pict I can find.

[img]http://i59.tinypic.com/24xjf2x.jpg[/img]

[img]http://i58.tinypic.com/iyd28l.jpg[/img]

15 psi at idle with muffs. Just a dribble out tell tail. Blew air threw all hoses ???

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Wonder if there is a leak where water tube goes into water pump. Might check to see if rubber liner is still in top of pump cover. In the water,... the copper tube would be submerged. See what I'm thinking?

Thanks. Ran it today and could set my hand on it without a sting or burn. I have water pressure gauge. Funny thought at the house 5 psi in water 20 psi. All I did was new T stats?

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Removing the liner won't make it run any hotter. The water pump will get hotter due to the exhaust blowing on top of it but never had a problem. If you can rest your bare hand on top of the cylinder head, without it burning you it's ok. If it stings, it's too hot.
I add a second sending unit to the port head for a gauge. There is a wire for the second sending unit coming out of the control harness right at the plug. It's with the trim/ tilt motor, trim gauge wires. It's tan or tan/ blue. The other end is with the gage wiring under the dash. Hope this helps..
I also run a pressure gauge. FYI...

I removed can and drilled exhaust on a 200 black max. Will it run higher engine temp with no barrier for the water pump and tube? At idle with muffs 143f water coming out. Water pressure 4. Don't want to cook it. Also any temp gauge setup besides that dumb *** sending unit?

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