Surface rust options

What should I be doing about surface rust on the engine, pulleys and engine mounts.




Thanks
The Dog

I used to sail on ocean-going tugs and dredges. To prep rusty surfaces for painting, after wire brushing but before priming, we used a product called "Ospho" (www.ospho.com). It's a green sulpheric acid solution that has the consistency of water. It converts surface rust to an inert substance that paint will cling to. Even if you don't paint over the Ospho, in my opinion, you'll be better off than leaving the rust as is. Here's what the directions say on the website:

OSPHO is a rust-inhibiting coating - NOT A PAINT You do not have to remove tight rust. Merely remove loose paint and rust scale, dirt, oil, grease and other accumulations with a wire brush - apply a coat of OSPHO as it comes in the container - let dry overnight, then apply whatever paint system you desire. When applied to rusted surfaces, OSPHO causes iron oxide (rust) to chemically change to iron phosphate - an inert, hard substance that turns the metal black.

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The smallest Ospho container I've ever seen is one quart. You can find it at paint stores that cater to industrial users, and some marine stores like Jamestown Distributors and West Marine.

Also, you can use Ospho to remove running rust stains. Using a rag soaked with Ospho and perhaps a brush (wearing eye protection and rubber gloves), I think you could remove those rust stains from your bilge.