water pump tube crack

[onebadc10]

My 1988 135hp mercury ran hot when throttled up but would cool down when i was at idle.it had week pee. I was going to replace the water pump.The impeller looks brand new but i did find this broke plastic tube.Could this be my problem?
what is this tube for?
Tony

 

[onebadc10]

Re: water pump tube crack/poppet valves

Re: water pump tube crack/poppet valves

just in case I have not made myself clear .i am working on both my1988 135s and they have different problems.I am working on the running hot problem now .
I thought I would clean and replace my poppet valves.One engine the housing is tapped and a hose runs to the top of the block.The other engins is not tpped in the housing and has a plug inthe top of the block. Any ideas why?
Tony

 

[rodbolt]

Re: water pump tube crack

there were several designs of the water pressure control based on engine seriel number not year model and even then you will find variations withinn a seriel gouping.
sucks but thats how they did it.
the plastic tube is simply a guide and melted at overheat.
only thing it does is aid in lower unit installation.