Thinking about putting aluminum heads on raw water cooled hp500's and concerned about corrosion issues. Just came across this "Zinc Saver Corrosion Control System for I/O engines". Does anyone have experience with a product like this, or thoughts otherwise?

I have no experience with that or this cheaper and closer alternative…some put screw in ‘zincs’ in unused threaded water ports in intake manifolds.

i have untreated alum heads for about 18 yrs. Very fresh water. When winterized (about 8 months sits winterized) i use real coolant that protects from corrosion. Yes, i reclaim all of each year.

Here are some magnesium ones for fresh water.
https://www.boatzincs.com/engine-mag...nly-sizes.html
I believe aluminum or zinc needed for salt ??? Not sure. Read up on what you need.

Pencil anodes are like $12. Magnesium for fresh water and zinc for salt/brackish. Put them in the intake or heads.

Go with closed cooling and you won't ever have to worry about it.

Best money I ever spent was on my CP performance closed cooling system. I sleep so much better at night....