1986 2 stroke 3 cyl major issue

[andrewss]

I have water coming out from around the spark plugs. Is there a plate with a failed gasket for the cooling system or something? This engine ran great in 2022 when it was last on the water. SN is (0A)7217467

Here's a link to a video
Video

Where do I start in diagnosing and fixing? Really hoping this a cheap and easy gasket...

 

[racerone]

Remove water cover that fits over the block.-----Inspect water cover and block.-----Clean gasket surfaces.----Install new gasket with a LIGHT coat of sealer.-----About 80 INCH LBS on the screws.

 

[andrewss]

Remove water cover that fits over the block.-----Inspect water cover and block.-----Clean gasket surfaces.----Install new gasket with a LIGHT coat of sealer.-----About 80 INCH LBS on the screws.

What type of sealer? Silicone spray? RTV? I've also heard engine oil?

 

[jimmbo]

If it starts leaking again after a while, the Cover has likely Warped. I had that happen on an inline 6. Cause was some water pump starvation do to over trimming the Engine. When went to the Dealer for the third time for the gasket, the Service Manager, ordered a replacement cover, gave it to me at no charge. I was told to install the Gasket(genuine Merc) dry with no Sealer. It never leaked again.

 

[Texasmark]

If it starts leaking again after a while, the Cover has likely Warped. I had that happen on an inline 6. Cause was some water pump starvation do to over trimming the Engine. When went to the Dealer for the third time for the gasket, the Service Manager, ordered a replacement cover, gave it to me at no charge. I was told to install the Gasket(genuine Merc) dry with no Sealer. It never leaked again.

I used to run my tower of power high in the water with the prop partially out of the water as I could hear the blades beating the water making a humming noise.....as you mentioned I too developed a leak in the water jacket cover and never thought about it was due to running like I was. Live and learn.