I have just rebuilt the engine on a 2003 FX140 Cruiser.
New pistons, rings and valves.

Now the entire ski is back together and for some reason after approx 5 mins on the hose the overheat warning comes. on.
I have triple checked all of the hoses etc. and all are fine.

Now I know water will only come out the right pisser when the thermostat is open. Stat is tested and working fine. But when I removed some of the water hoses with the water flowing, no water comes out only steam.

Anyone know of any reason why this is happening