Cleaning Outdrives - Which cleaner?

D

douglee25

Well-Known Member
Jan 13, 2008
4,761
Dallas, TX
Boat Info
Cruisers 3575
Engines
Twin 7.4l
I pulled my boat after being in the water for two months. The outdrive, props, and the topside of the trim tabs were covered, and I do mean covered in algae.

It took me approximately 1.5 hours of scrubbing to get the drive back to almost new. I've read some posts about using a diluted solution of muriatic acid. What are your thoughts? What dilution ratio? I know muriatic acid will technically dissolve or etch aluminum so I want to be sure I'm going about this in the right direction. What about the paint on the drive? I just painted the drive so I want to make sure I preserve the finish as best as possible.

Are there any other cleaners that might work just as well?

Thanks again.

Doug
 
I used a diluted solution of muriatic acid to clean some serious calcium deposits off my Alpha drive. I believe it was a 14% solution to start with, then I diluted it 4:1 with water. It was extremely effective.

I can't tell you what concentration vs exposure time is safe, but I can tell you I used the above by spraying it on, and hosing it off about 30 seconds later with no damage the drive. You could see the reaction where the acid contacted the calcium build-up, but there was no visible reaction from the painted drive. To play it safe you should neutralize the acid when you are finished with a baking soda solution on everything the acid touched.

Safety disclaimer: Wear proper protection, gloves, glasses, mask, long sleeves, etc.
 
a dishwashing or toilet brush, 5 gallon bucket water with 3 cups of Simple green and a quart of "L-bogreece". Followed by 2-12Oz Daddy pops.
 
Slimy Grimy works very well, too. So does a pressure washer.
 
douglee25 said:
The pressure washer wouldn't touch it!

I will have to give some of these solutions a try.

Doug
Click to expand...

No offense meant here, Doug, but is it a good one? Did you get close enough? I've powered through some really thick stuff with a pressure washer.
 
Lazy Daze said:
No offense meant here, Doug, but is it a good one? Did you get close enough? I've powered through some really thick stuff with a pressure washer.
Click to expand...

Oh yeah, it'll take the paint off before it will take the algae off. I'm telling you guys, this stuff was so thick and slimy. It took a ton of elbow grease to get it off. I was surprised as hell.

Doug
 
douglee25 said:
Oh yeah, it'll take the paint off before it will take the algae off. I'm telling you guys, this stuff was so thick and slimy. It took a ton of elbow grease to get it off. I was surprised as hell.

Doug
Click to expand...

Wow! Remind me not to visit your waters! :grin:
 
Zing is muriatic acid and is sold at marine stores. It is designed to remove algae and other crud from outdrives and boat bottoms. As soon as you spray it on, the algae foams and bubbles. Just use a brush to move it around all over the affected area and hose off. The drive will look like it's brand new with little or no scrubbing. I've used the product for years on my Merc outboard motor.
 
Well I did some researching this afternoon after reviewing the MSDS sheets on some different hull cleaners. The active ingredient in most cleaners is hydrochloric acid also known as muriatic acid. Muriatic acid from Home Depot is 14% concentration. I found that Lysol toilet bowl cleaner is 10%. I bought the lysol cleaner and it worked great.

Thanks for the help.

Doug
 
Nice investigative work! :grin:

If you want to go a little greener - and safer, next time give the Slimy Grimy a shot. We sell a lot of the stuff at the store - no complaints, yet. Works nice on wooden decking and fences to brighten and get rid of that green mildew. Apparently (haven't tried it) it gets rid of oxidation of aluminum and galvanized trailers.
 
Lazy Daze said:
Nice investigative work! :grin:

If you want to go a little greener - and safer, next time give the Slimy Grimy a shot. We sell a lot of the stuff at the store - no complaints, yet. Works nice on wooden decking and fences to brighten and get rid of that green mildew. Apparently (haven't tried it) it gets rid of oxidation of aluminum and galvanized trailers.
Click to expand...

Thanks for the heads up. I'll keep it in mind for next time.

Doug
 
I'm not a big fan of pressure washers and boats. They tend to force water into places it isn't supposed be, like around deck fittings, etc. Merc warns against using them on outdrives as they can damage seals and force water into the drive.
 
keokie said:
I'm not a big fan of pressure washers and boats. They tend to force water into places it isn't supposed be, like around deck fittings, etc. Merc warns against using them on outdrives as they can damage seals and force water into the drive.
Click to expand...

I agree. I just tried it on the skeg initially to see if it worked or not as the hose by itself did little on the first go around.

Doug
 
Kurt said:
That is too funny, I kept looking at that saying to myself, ""That is not any amino acid I have ever heard of?"

Zing is a product I use, check it out.
Click to expand...

the product I mentioned........It works!
 
Guys, don't be afraid to use a pressure washer. It won't hurt the metal on the drive, it won't hurt fiberglass. We use them all the time at the shop. Do we point the PW into water passages and other sensitive areas? No, of course not. A little common sense is all you need - if you have that, you'll be fine. Merc and Sea Ray have to cover their a** on topics like this. Otherwise, in our sue-happy society, they could be liable.

But, I digress. Doug, again, glad you got it off easy. That really was pretty ingenious using that Lysol! Where I boat in Maine, stores are not exactly "right around the corner". I'll be remembering that Lysol trick - thanks!
 
Lazy Daze said:
But, I digress. Doug, again, glad you got it off easy. That really was pretty ingenious using that Lysol! Where I boat in Maine, stores are not exactly "right around the corner". I'll be remembering that Lysol trick - thanks!
Click to expand...

I figured I could always try the 14% muriatic acid if the Lysol didn't do the trick. I'm sure that will make it to Gary's new book. Weird but it worked.

Doug
 
You must log in or register to reply here.

Forum statistics

Threads
113,247
Messages
1,429,244
Members
61,127
Latest member
Ants84245srv
Back
Top