Will muratic acid hurt the paint?
my boat has a base coat clear coat paint job and I was going to use muratic acid to clean the transom and bottom of boat.
If I get muratic acid on the paint will that make wish I didn't.

trying to get rid of a stain? If so go to the pool store and get "Stain & Scale Remover" mix about 3 oz to 2 gal of water. Takes about 30 minutes and the stain will be gone. Nice thing about this it's not harsh like an acid. I use a garden sprayer to do my boat.

I am trying to get the yellow stain off the bottom that I get from the summer use.

Go to any Marine supply and get "On/Off". Try not to get any on the trailer if it is galvinized.

muriatic will attack any metal it touches (rubrail, cleats, trailer...etc).... i would not use it...

I use the wynn's (pro) product to clean boat and it's the better product I have try. For yellow stain use the c-44 or c-45 power lift. Apply and wait ten minutes, after wash with soap. I have a business in car wash and it's the same product i use with a new car.

Interlux makes a boat wash & a stain remover that works well. We use it on our Donzi & our friends use it on their Fountain with good results.. (also there is no stink & no burning. It smells citrusy)

www.lakesiderestorations.com

Here in Western NY most use a product called Slimey Grimey.

Tom,
Go ahead and clean it with the acid, urethane clearcoats are very chemical resistant I cleaned the old boat that way all the time and we painted it. Worst case might be after multiple cleanings that you might get a slight haze that will buff.
You don't let your boat get that dirty anyway. Toilet bowl cleaner works as well.

aluminum wheel acid works well too