Mercury 300 pro max water leak

[mikeyg]

Hey all,

Long time reader but first time poster, I recently bought a 1998 mercury 300 pro max and used it on the weekend. Great engine but I noticed while flushing it after using it that water is pouring out of the top near the driveshaft, I know from my years around outboards that this shouldn't happen. My question is has anyone else ever had this and what could it be?

https://vid.me/cSCd

[blackeye]

The same thing was happening with my 300 pro max this season and my mechanic told me it would be the gasket between the midsection and the power head. Upon taking it apart we discovered that someone, likely the previous owner, had used an incorrect part which didn't allow the power head to mate properly with the midsection. I think my case was unusual and yours is likely the gasket which I believe requires pulling the power head. Good luck and let me know how you make out.

[XstreamVking]

x2 on the p/h gasket.....Not too bad of a fix, make sure the mating surfaces are real flat and clean. Good time to check the lower crank seal also. New upper water tube rubber grommet installed is a good thing too.

[mikeyg]

turned out to be a broken engine mount clamp with blown head gasket, all fixed ready for summer

[Sea2jet]

Thanks for updating. Sure is nice when someone lets everyone know the outcome.

[blackeye]

thanks for updating. Sure is nice when someone lets everyone know the outcome.

x2!!!!