90 mariner fouled plugs

[megtymarn]

Hi I have a 90 mariner outboard checked my plugs and all were oily and damp> (not that bad and motor ran well) I have since change all plugs. ran motor for 10 min. pulled bottom plug and there was a white paste kind of creamy. Motor still runs good.

anyone have any feedback would be greatly appreciated,

thanks

 

[achris]

Re: 90 mariner fouled plugs

White creamy means water is getting into the engine. Not good. You didn't tell us if it's a 3 or 6 cylinder, but usually it's the exhaust cover gaskets.

 

[Chris1956]

Re: 90 mariner fouled plugs

Water in the lower cylinders could also be from a leaking crank seal. If you overhaul the motor to fix the problem, replace the crank seals as well.

 

[megtymarn]

Re: 90 mariner fouled plugs

Mariner 90 is a inline 6 cyl. not sure what year maybe mid to late 80`s