Need help with 73 Merc 500 water issues

[Steve R.]

I just bought the boat and motor and the guy I got it from said he noticed there no water coming out of tell tale.
The first thing I did was a new impeller kit and it needed it , but when I fired it up there is water leaking from under the top plug and the bottom spark plug. Is this a major repair ?

Mercury 500 50hp
ser# 3479512

 

[Steve R.]

Re: Need help with 73 Merc 500 water issues

Thanks for all the views guys but I guess no one has ever had
this problem It looks like a head gasket to me. I have a manual on order so I
get figured out I hope .

 

[oldman570]

Re: Need help with 73 Merc 500 water issues

It is just a water jacket gasket that is bad and can be easyly replaced. Getting a manual is a very smart thing and will come in handy when working on the motor.
Oldman570

 

[Steve R.]

Re: Need help with 73 Merc 500 water issues

I pulled the lower end back off and put the hose to the water pickup tube and water comes out around the spark plugs. Checked the plugs no water in cylinders but no water came out the tell tale line just around the spark plugs .

 

[MykeC]

Re: Need help with 73 Merc 500 water issues

I just had the same issue a few days ago and replaced the water jacket gasket. I actually cut my own out of gasket material. It's an easy fix.

 

[aussieflash]

Re: Need help with 73 Merc 500 water issues

Tell tale probably blocked as they often do.Stick wire or whipper cord up hole while running.If not check all hoses for blockage or bad connections.