To sandblast aluminum power head cover or not to sandblast the cover?

[hotrod53]

My '77 Merc 500 top power head cover was peeling and looked like heck. Last year I sanded and feathered all bare metal and bad edges. I used aluminum primer followed by Mercury phantom black and Mercury clear, after buffing it up, it shined like a new penny! Before the year was over, I started noticing the clear starting to crack. The next thing that I know, the entire piece is cracked up and it's starting to get bare spots where I can see bare aluminum.

Should I sandblast the piece, or should I chemical strip it? I have access to a blast cabinet, I just dont want to create any more work than necessary, and I surely
don't want to do this a third time.

 

[MTboatguy]

There is no reason to not blast it, if you have the correct media, then clean it really good, prep and paint, I would recommend baking it in your oven if you do that, then you will end up with a more durable finish that might not be as prone to cracking, if you do bake it, do at low temp, 200 degrees or less that way you don't run the risk of warping anything. I have sand blasted quite a few parts over the years then painted and baked, one was an old aluminum steering wheel for one of my boats and that finish is still holding up with no problems and I did that over 10 years ago. I would not expect a cover to last that long due to what it actually goes through, but it will last better than just painting it.

 

[gm280]

Go for it. I sand blasted a lot of aluminum engine parts without ant issues. No reason not too...

 

[robert graham]

How would it look to sand blast it to the bare aluminum and just leave it to "age" naturally?....no more cracking/peeling paint to deal with....maybe a flat/matte aluminum finish might even conduct heat better?....just a thought...