| | RE: Yamaha OX 66 Pressure Relief (poppet) Valve
The purpose of the popit or pressure relief valve is to let the cooling system build water pressure up*to keep the system under pressure. If the valve is stuck open(weak spring, crude on the valve seat) the water will not reach the upper parts of the engine since its being dumped out the open valve. Usually a indication of this happening is the engine overheat warning goes off at low engine speeds even though there is a good stream coming out of the engine. The reason is... the valve being open and the cooling water level in the upper part of the engine is not high enough. This is were the overheat sensor is located and if does not have water around it, it activates
__________________ Andy Munao
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