92 40hp merc leaking water

[skipper123]

I have a 1992 40HP 4cyl merc that has a sensor beside the top spark plug. The sensor seems to be held in by orange silicon rubber and water is squrting out beside the sensor. My question is can I pull out the sensor and reseal it and just push it back in or is the sensor threaded in. I bought the boat 4 months ago have run it at least 50 miles and has run great. Dirt daubers stopped up
the pee spout for the second time and this seems to have made the water leak worse. I think it has always leaked a little because I have noticed a little water coming out of the hood area and could not find the leak.What do you guys think about the sensor ?

 

[verado7]

Re: 92 40hp merc leaking water

yes it could be the sensor - try resealing it first buyt is i suspect it is the water jakcet cover gasket .

 

[skipper123]

Re: 92 40hp merc leaking water

Just ordered a new gasket from marinepartsplus.com Does anyone know if there is a special sealer that should be used for head gaskets. It looks like it may be the gasket, water is coming out below the spark plug. Just a trickle until the dirt daubers stopped up the pee tube then a spray.