Well I have bought a large handful of wet automotive sandpaper, and I want to give my engine bay a go to try to get the original color back. All my surfaces feel like overspray and are relatively rough. I think if I knock down all of this it will get the grime out and feel/look more OEM. I have tried soap and water and that did help a tad, but some of this stuff is just too set in to come out.

Can people give me a few basic 'do no harm' wet sanding techniques that I can try? I want to get the engine bay in a more detailed finished look. Thanks!

I used full strength Simple Green and fine steel wool. Worked pretty good at getting most of the grime off. I've heard of some who wrap up as much of the wiring as they can with aluminum foil, then used a "green" oven cleaner (one that doesn't generate heat).

I bought this stuff a few years back and it works great I had rust on my driveway and this stuff took it off. I have also cleaned my sons dirtbike engine with it and it made it spotless.

The stuff i bought was the green it cuts right thru grease and oil. it might be worth checking out.

http://www.advanage.com/

I think steel wool or sandpaper will dull the finish too much. You might think about "clay baring" it. I have clay bared several cars with overspray and I have always been impressed on how well it works. I have always got a glossy, smooth result even with sandpaper like overspray. You might have to use a bit of degreaser on the dirty bits but I suspect clay bar will do the job after that.

I think that sandpaper is way too agressive, give the many irregular surfaces in the engine bay. The chances of going through the paint in high spots is too great. Why not just use rubbing compound/polishing compound?

clay bar and rubbing compound have been tried, worked great on the dirty bits, but the parts I want to fix now feel like rough overspray, not just dirty paint. They are not just visually dirty, they are tactile and rough.

clay bar and rubbing compound have been tried, worked great on the dirty bits, but the parts I want to fix now feel like rough overspray, not just dirty paint. They are not just visually dirty, they are tactile and rough.

Wow, if clay bar won't touch it you may be stuck with sand paper and bringing the gloss back with compound.

Keep the sandpaper at 1000 or higher, and keep water on the areas you are sanding. After 1500 or so you can hit it with rubbing compound.

This is what happens when you sand with too much elbow greese and not enough water...

http://www.classiczcars.com/photopost/showphoto.php?photo=33106&ppuser=14083

Oh, man, I will be VERY careful.