Carbon streaks

[tarheel53]

Hey guys - 2003 F150, 550 hrs. I've begun to notice streaks of what looks like exhaust residue or carbon coming out from under the plastic cowl and running down the sides of the lower unit. Does not have an oily feel and will wash off with water / hands. Is this a sign of an exhaust leak somewhere - anything to be concerned about ?

Thanks, JB

[robert graham]

Maybe remove upper cowling, start the motor on the muffs, check for source of black streaks?....

[tarheel53]

Good idea ....... just hoping this was not an early indication of the dreaded exhaust corrosion I've read about

[robert graham]

Not a bad idea to clean the motor under the cowling....a little spray Windex and a very low pressure garden hose can keep oil, grease, dust and grime off motor so you can better see leaks, loose fasteners, cracked hoses, etc....I use a light spray lubricant and an old toothbrush after motor is dry to keep a very light protective film on everything....sorta like you might use on a shotgun or rifle to prevent rust....

[tarheel53]

Good idea ......... hopefully just built up crud working its way out from under the cowl .......... will give the cleaning suggestions a try.