Is Waxoyl a worthwhile treatment?

My 11-year-old Focus Diesel Estate is showing signs of rust. I was advised at the last MoT to get it waxoyl. Please could you tell me what is the general advice on such?

Asked on 25 November 2019 by morsetaper

Answered by Honest John
Before you Waxoyl you need to treat the rusted areas with rust remedy and renew any seriously rusted metal by welding. In the high condensation this time of year, attempting to apply Waxoyl is a complete waste of time. It can only work when applied to clean and bone dry metal. Spray it inside a damp door and it won't stick to the sides. It simply bleeds out of the door bottom drains.
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