Can combi colour be applied on top of old sanded/prepped paint(oil based) on a narrow boat?
This is not a marine paint but assuming the area to be painted is above the waterline, not subject to traffic, Rust-Oleum CombiColor Original could be used.
We would recommend a test for compatibility and adhesion is undertaken on a small area prior to full application.
The substrate should be clean, dry, sound and prepared as detailed in the technical data sheet.
As an alternative requiring the same testing and preparation we can recomend Teamac Marine Undercoat followed by Teamac Marine Gloss.
This can be mixed to many RAL, NCS or BS colours in a gloss finish.