dried white stuff on sterndrive

[Lou McGoldrick]

I have some baked on white junk on my sterndrive. I thought it would come off with a power wash, but It didn't.
Must be some lake water algae that has been baked on for years.

Is there some cleaning chemical that would take it off. It came with my boat. Thanks for any ideas.

 

[Dieter]

I think normally this is hardness deposits like calcium and lime that get baked on the drive from heat. Try CLR or similar

 

[Lou McGoldrick]

I think normally this is hardness deposits like calcium and lime that get baked on the drive from heat. Try CLR or similar

Thanks Dieter, that sounds exactly right, I'll try it and post how it works.

 

[o2batsea]

It came with my boat.

Hey, (Seller) could you clean the boat before I take delivery? Thanks!

 

[Lou McGoldrick]

I think normally this is hardness deposits like calcium and lime that get baked on the drive from heat. Try CLR or similar

Thanks Dieter, I used CLR four times, and also used steel wool. The worst of it came off, I'll finish it off later, it was hard work.

 

[o2batsea]

UGH bronze wool or scotchbrite. Steel wool embeds weeny microscopic shards of steel in the paint.

 

[Dieter]

Problem is when on a plane the upper is out of the water and gets hot, baking more stuff on. So removal is temporary, just need to keep after it, probably the first time it's been done. in the end more cosmetic issue than anything else.

 

[Oldsalt&au]

After a clean I suggest using an anti foul paint. May not stop it but the paints sacrificial.

 

[805HD]

Drive shower?

 

[PeterDE]

I have the same problem with my sterndrive. Every year i clean it off, repaint, and by the end of the season it's back. The Mercruiser guy at the local Mercury Marine shop said it's due to chemicals in the lake, mainly from fertilizer run off. I'm not a chemist so I don't know if that's true or not. I do know that the lake I use does have a lot of crap in the water. So it's become part of the annual spring fitting out. It's unsightly but doesn't seem to do any actual harm.

 

[bondo]

Ayuh,...... I can't see it from the helm,....... so who cares,......

Ya goin' Boatin',..?? or to a boat show,..??

 

[Lou McGoldrick]

Thanks Peter DE, I think my white stuff had accumulated for years, and sat in the sun between seasons. It was very hard to clean off. It is chemical, like hardwater plugs a shower head. Wouldn't think it was from fertilizer. I plan to power wash off at end of season. Anything to help prevent future buildup. Your right, it doesn't seem to do any harm, but doesn't get better with age.

 

[PeterDE]

I just use a power wash to get it off. Does a good job. I do know enough about metals that, I know it is not stray current corrosion, galvanic corrosion, or any corrosion I've ever seen. . It's some chemical that adheres to the metal in the sterndrive. I looks really bad but doesn't seem to cause any problems. I have tried various paints (including Mercury Marine's own) and nothing seems to stop it. I haven't tried a marine anti-fouling paint though. Maybe next fall

 

[bondo]

It was very hard to clean off. It is chemical, like hardwater plugs a shower head.

Ayuh,.... Calcium, 'n lime,..... CLR will take it off,.....