2000 Merc 150 Hp Cooling water leak

[honch057]

I have a cooling water leak under the engine cover of my 2000 carburated 150hp merc. It is coming from the starboard side lower block area, out of a component that appears to have a weap hole. Best I can tell from the Clymer manual is that this is the poppet valve assembly. If so, what does it do and where should this water be going. Am I missing a fitting that goes to somewhere? Where should it be plumbed to? Should water be coming out this hole? Help is greatly appreciated.

 

[ronmold]

Re: 2000 Merc 150 Hp Cooling water leak

You have a hole in the poppet diaphram, It needs to be replaced. If the hole gets too large it could stop the poppet from opening or staying open thus reducing the cooling at higher RPM's.

 

[honch057]

Re: 2000 Merc 150 Hp Cooling water leak

So I assume there should be no water coming out of that hole? The diagram shows there "may" be a hose fitting there. However there is an asterisk showing NOT USED ON ALL MODELS. Were does the poppet relieve the excess pressure to? My water is going inside the motor housing which doesnt seem right. I noticed the water once after tilting up the motor when returning home, water came out of the control wires inlet in front of the motor. Did a static flush with the hose and found the water coming out of that hole. Thanks again

 

[ronmold]

Re: 2000 Merc 150 Hp Cooling water leak

The excess pressure at the poppet comes from around the cyl. water jacket and when it opens dumps water out the exhaust. No that hole only tells you that the poppet diaphram is bad.