80hp Mercury Poppet Valve

[allegiance]

I have a 1987 80hp Mercury outboard. The engine was overheating so replaced the thermostat. That problem is solved. While I was doing this I also replaced the diaphragm on the poppet valve. Since I changed this the pee stream is excellent. The question I have is that when I have motor running in my driveway with the muffs on and after I turn off the Engine and then turn off the water the pee stream continues to come out for about 20 seconds and then peters out. I know I am over thinking but I never remember the pee stream continuing once the engine was cut off. So is this normal?

I am also struggling to understand how the poppet works. A plastic piece fits snuggly into a rubber gasket and the diaphragm is screwed with a circular plastic piece on top following by a spring then the cover. looking this over from an engineering point of view I do not see how the spring works as the plastic piece connected to the rubber gasket does not allow this to move at all.

Thanks,

John

 

[Chris1956]

Poppet valves on Mercs open when the water pressure causes them to overpower the spring closing them. They allow lots of cooling water to flood thru the motor to cool it off at high RPM.

Any other questions?

 

[Faztbullet]

I have motor running in my driveway with the muffs on and after I turn off the Engine and then turn off the water the pee stream continues to come out for about 20 seconds and then peters out. I know I am over thinking but I never remember the pee stream continuing once the engine was cut off. So is this normal?

Yes this is normal as the "P" come off exhaust plate which is before t-stat and poppet,

 

[allegiance]

Thank you both for your feedback. Will take it out this weekend and let you know if i have any issues.