Waterpump sucking air

[jacko]

" How can I tell if my "ne

" How can I tell if my "new" waterpump is sucking air?How do I fix it? My 1980 9.8 merc throws no water at idle and intermittant at higher rpm's. I am fairly certain there is no blockage. Thanks for your time, jack "

 

[bigreenbass]

I had a 1986 35 hp merc that

I had a 1986 35 hp merc that did the same thing.
When I disassemled the water pump I found three of the vanes on the impeller had broken off due to age.

 

[sparky]

There is a plastic washer at

There is a plastic washer at the top of the water tube on some models.I have seen it melted and blocking water flow.

 

[jacko]

" Update! New water pump housi

" Update! New water pump housing solved this problem. Many thanks to all,jack "