River water deposits on lower unit - what to do...

JoeMan

Petty Officer 1st Class
Joined
Jun 29, 2006
Messages
322
Bought a Merc outboard motor which unfortunately spent the last 3 months hanging on a pontoon in the Fox River in Chicago (always IN the water of course), it sustained some 'attack' to the lower unit finish. Nothing is damaged mind you, but the lower unit was covered with slime, little tiny red worms, and some serious water deposits. All I've done thus far was to scrub it up and get the big stuff off. No chemicals or anything. The thing is, now it hangs off the back of a completely restored little runabout, and it looks bad! Any help here?
 

NBE

Petty Officer 1st Class
Joined
Oct 28, 2003
Messages
354
Re: River water deposits on lower unit - what to do...

You could try straight vinegar or try a lime/calcium remover such as the bathroom cleaner CLR or something similiar. These usually work for me pretty good.

Someone else may be along shortly with more suggestions.


Good Luck!
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: River water deposits on lower unit - what to do...

Good suggestions for cleaning. If you want to take it further and repaint it, strip off the old remaining finish and you will likely find a green or yellow primer coat underneath. That's the original self-etching factory primer. Once there, use some non-detergent steel wool or wet-dry sandpaper to roughen up the surface a little. Then clean it soap and water, the vinegar to remove dust residue, then soap and water again. Then you can repaint it with self-etching primer and use a compatible paint to replace the original paint top coat. If you don't use the right primer and paint the finish/paint will just start bubbling/flaking off after it's been in the water a few times. Not a hard project to do...but take the time to do it right the first time if you go this route.
 

tiller7104

Petty Officer 1st Class
Joined
Dec 23, 2005
Messages
352
Re: River water deposits on lower unit - what to do...

My boat spends its time on the delaware river with similar residue minus the worms LOL I have used 409 on it for ever and it brings it back to new, granted it is not left in the water but give it a try!
 

JoeMan

Petty Officer 1st Class
Joined
Jun 29, 2006
Messages
322
Re: River water deposits on lower unit - what to do...

Lots of great ideas. I appreciate the advice guys. I'll try the cleaning agents, and if not successful, I'll repaint her. THANKS!!
 
Top