If you are getting off some dusty grease, then liberally use some brake cleaner or carb cleaner. It's xylene and disolves grease well, however I find it under my watch band often and I get a rash if it stays more than a minute or so, be advised it's an irritant.
Also "purple power" from your local is pretty handy as well. I use it one wheels and tires to get brake dust off and just to clean them in general. it works well on grease if it sits. DON'T get close enough to inhale the mist, it burns like shit.
If you are removing rust from the "old rusty Jeep" you dont have too many options:
1. Use a wire brush or a wire wheel on a drill/air tool and remove all the oxide (rust). You'll be left with pitting most likely depending on how rusted the part is and also how thick it is. This door metal for example will be a hole after a wire wheel if severely rusted to begin with. Now comes the welder to fix the hole.
2. Use POR-15. No personal experience with it, yet. Supposedly you just clean off the loose stuff and paint it on to the rust and it completely stops the rust from progressing. O% vapor can get through to continue the oxidation. Comes in several colors and I heard if you're mixing it and drip 1 drop of sweat in it, then you have f-ed up that whole container. Just a heads up, but I don't remember where I read that. Maybeon the site.
3. You can use this following method to get rid of rust completely. But this is all dependent on the part size. I would use this on a steel rim, or maybe a door handle, mirror etc. Nothing too large.
http://www.metacafe.com/watch/456478/rust_removal_tip/
Handy stuff but more time consuming most of the time.
After you have stripped the rust off the metal, it is important to remember to coat the metal with paint or por-15 or powder coating etc. to continue the rust-free environment. Air or water or corrosive substances on metal= corrosion ( and by metal I mean, steel, or iron. Aluminum can corrode but it is much slower. Believe it or not "stainless" steel can rust depending on the alloy. Pretty much anything can under the right conditions....other than rare precious metals like gold and platinum.) I would really only be concerned with putting a coating on steel/iron due to the reactivity rate. If you have a vehicle with no paint it wont rust as long as you keep it all oiled. My leaky rear main seal has kept my underbody from rusting, however it has also taken alot of the good coating off the underside of my XJ too.
I think that pretty much covers grease/rust removal. If you have any further question, just ask here or PM me.
--Alex
