Help water on 2 plugs

[StratosRob]

Well let me start off telling you it is a Yamaha 40 HP. 6H4L402632 Precision Blend.
The top two cylinders keep getting water in them not alot (about a Tea spoon at a time) Running on muffs.With new gas. Motor ran fine until I put the muffs on. Removed the head thinking it maybe a head gasket but the gasket looked fine. Removed the exhaust cover all gaskets looked fine there to. I do not know any history about the motor besides they where going fishing and it started to skip. Can anyone tell me what year this motor is also. Thanks for any help.

 

[cbavier]

Re: Help water on 2 plugs

I hope your not turning the water faucet on more than half way. If you do you may blow a Gasket or ______

 

[Silvertip]

Re: Help water on 2 plugs

If you installed the same head gasket you will never know if that was the problem? You never reuse a head gasket. Full water pressure will also not blow a head gasket. The muffs will blow off well before that happens and there is a heck of a log more pressure trying to get out of the cylinder when the engine is running than there is water pressure trying to get in. The gasket is either bad or you have a cracked block from an overheat condition that someone ignored. Water pump been replaced lately (if at all)? Thermostat or bypass valve stuck shut?

 

[cbavier]

Re: Help water on 2 plugs

Silvertip: Not to argue with you because you obviously have more experience than I do, but my Mercruser Owners manual says . DO NOT TURN THE FAUCET on more than half way. Of course I suppose than might depend on how much water pressure you have too. An OutBoard may be different than an I/O too?