My buddy just bought a 58 Sea Ray with a blue hull. It's in good shape but we "waxed" a few sections a couple months ago to see what would hold up and look best so he knew what to use this winter. We used Sea-Shield Exhaust Guard after polishing in one spot and Carpro's Cquartz and reload on another part.
Both seem to have held up really well. My experience with both products, as I used both this year too, is that Exhaust Guard works best at the waterline or anywhere near diesel soot. It' just wipes off with boat soap and water, until the wax is gone. That's the problem, it doesn't last the whole season, maybe 4 months and it's the waterline that goes so it's hard to reapply in the water.
The CQuartz is awesome stuff. I did my superstructure with it this year. They say to apply reload or Hydro2 every 2-3 months. I use the Hydro2. After washing, while still wet, I spray the hydro2 on an area, then rinse with the pressure washer. It takes an additional 15 minutes to do the boat. I did it twice this summer and it makes so much difference in the state of the boat and eases washing an unbelievable amount. black streaks wipe off with my dry finger in most cases. In bad spots (my transom under the canvas) I have to use a cloth with some soap and water! I used to have to use cleaner wax there every week.
I'm going to try CQaurtz on the whole hull with Exhaust guard on top around the waterline and see if that works too.
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