I ran across a post in the wooden boat forum about flushing
a heat exchanger
with a solution of phosphoric acid and water
at a mixture of 4 parts water
to one part acid.
heat exchanger cleaning
Could a mixture of, say, 8 to 1 be used with a old tooth brush to scrub down things like the the stuffing box or through-hull valves? Then neutralized with a scrub of baking soda and water.
Would it be productive and practical?
Also, sometime ago there was a post by "Captforce", I believe, about making a paint-able mixture out of 3M 5200. Cant find it again.
What was it mixed with? acetone?