water pump issues just exhaust coming out

[albertaborn]

so ive been battling with my 7.5 mercury motor for far too long.When i got the motor the water line was plugged and it overheated the engine so the guy sold it to me for cheap.i tore it apart cleaned it all out, blew out water passages with air and fed a wipper snipper wire through just to be sure. i changed the rubber grommet at the top of the water feed tube and all the gaskets on the engine and base. theyre is not an old gasket left. i put a new impeller in and tested it with a drill on the drive line and it flows real good.reassemble the engine and fire it up but no water just exhaust. i then took the pull start off and put a drill on the flywheel and i can get water up to the thermostat and bleed off.in my mind it seems like exhaust is still getting into the coolant system. any any ideas would be great.i changed the baffle plate as well.

 

[Buzzwindrip]

Re: water pump issues just exhaust coming out

I have the same motor, and had pretty much the same issue when I picked mine up for cheap. It is still sitting in my basement with the LU off, waiting for some new pump parts. One of the replies I got to my exhaust-out-the-indicator query was that it was picking up exhaust in the test tank, as the water inlet is right above the prop exhaust. It was also mentioned the problem may be compounded by clogged up idle exhaust relief ports at the back of the lower cowl. Good luck, at any rate.

 

[albertaborn]

Re: water pump issues just exhaust coming out

i checked the idle relief ports when i had the powerhead off when i did the top end and gasket change over. as far as the turbulent water in the garbage can i can see how its a valid point but i did take it out to the nearby river just to see if i could get any results and did not. in my opinion i either have a leak in the waterjacket somewhere or something else. what have u replaced on your engine as far as new parts. im impeler,gaskets,pistons,baffle plate,copper tube grommets. maybe the powerhead base gasket might have a leak or something i guess maybe i should get a new one anywho....

 

[albertaborn]

Re: water pump issues just exhaust coming out

so if i pump water up the copper tube how much water should come out the relief ports? i ve tried with the thermostat out and in no dif