1988 yamaha 225 excel overheating.

[hjjack]

I Have A 1988 Excel, Runs Great But The Stream And Water Coming Out The Exhaust Is Very Low. I Have Canged The Prv, Thermostates Amd Water Pump Impeller, No Change. Can Anyone Tell Me If A Blowen Head Gasket Can Cause This. I Removed The Lower Unit And Attached A Hose To The Water Tube And Water Flowes Through The Engine. On The Top Of The Engine Behind The Thermostates Is A Plug Screw, With The Hose Attached And Plug Removed Water Shootes Out The Hole. When I But Back The Lower Unit And Run The Engine Air Puffes Out The Hole.

[boats.net]

Yes a blown head gasket could cause it(would run bad and see water on spark plugs) or plugged water passages in engine. Check water pump housing, may be melted at top and need new one.