I had my 350 block dipped and everything, well i was dumb and didnt coat it right away with oil. But did get to it alittle after. On the outer casting theres weird brown spots, as for anything internally there's a slight bit on the cl surface walls. What can i use on the engine casting without scuffing it and what about the cl walls. I want the best safe way of doing this. Not the "this will get it done" kinda thing lol you know what i mean. I want to get the motor back to looking like it was just cleaned up again.

 

Why not paint it and forget about it?

 

Cause there has to be some sort of liquid substance that will fix this, and what about the cl walls.

 

Cylinder walls? Run a light hone through it.

 

I would think that a light scrub with steel wool would be fairly harmless, and would get all the rust off the cylinder walls...

 

Wipe down the cylinder walls with WD40 on a white paper towell (the thicker ones are better). Just keep spraying the paper towell with it and wiping the cylinder until it doesnt come out dirty anymore. Keep switching sides and get new paper towells frequently. The WD40 will then keep a thin coating on the cylinder walls to prevent any more rust from forming until you put it all back together with real motor oil.

As for the rest of the motor, use some mineral spirits on a cloth or something and wipe it away. Surface rust that forms immediately is very easy to get off if you arent lazy. Spraying things with liquid never works as good as if you take some time and do it right. Dont half-*** it and it will come out fine, plus after you let the mineral spirits dry you can prime and paint right over it because it wont leave behind residue like the WD40 would. I've found the best way to do it is clean it all up with the mineral spirits and rag, and then hit it with the heat gun to warm up the metal and evaporate any moisture that is on the surface. Without the moisture there it will slow down how quick that surface rust forms again and give you time to paint.

 

thanks 85. I appreciate that greatly!. I was searching and also found for the block casting a thing called "Zud power"?. Has an Oxalic acid that you mix with hot water and make a paste. Apply, let it dry, and then rinse off. Any experience or knowledge on that? Where would i get "mineral spirits" thank you tonz for replying.

 

Mineral Spirits?...Home Depot or probably any paint store.

I wonder is a non-stick cooking spray would work as good/better than WD40. I got it! Teflon cookingware spray. hehehe

 

cooking spray!?! Not too sure about that one. WD40 is your best bet. I love the stuff. I go through it gallons at a time. It is primarily kerosine so that's what gives it the degreasing ability and it also has a mix of other oils in it to lubricate. Ive tried other things when I rebuild engines to clean up the cylinder after it has been bored and honed and nothing works better than WD.

Mineral spirits is basically paint thinner. It will be in the aisle at the hardware store right next to the paint thinner, cant miss it.

As for oxalic acid, it is a rust remover and is an ingredient in many rust removers you would buy at the store and is also used to bleach wood. If it was my engine I would just wipe it down with the mineral spirits to clean it up. Even if you use the acid to clean it you will have to hit it with mineral spirits or some other solvent to remove grease and oils before painting, so it just removes some steps doing it first.

Another option which I use regularly for heavier rust is OxiSolv rust remover from Eastwood. It has phosphoric acid in it which reacts with the rust and forms zinc phosphate, which no longer reacts with air to form rust. You can then paint right over this. I use it for bolts, sheet metal, brackets, everything that has rust and it works like a champ. If you go this route though dont get it on your cylinder walls or internal engine surfaces.

OVERALL though I suggest you just take an hour or two and clean up the motor by hand with the mineral spirits, no danger of more water on the block to cause rust, it will degrease it, its cheaper ($4.00 or so for a gallon), and it will probably work the best in the end. Good luck man, kinda long but hope I helped.

 

hell yeah man, you helped out a great bit. thank you

 

Hydrochloric Acid will work great, but it may be a little too caustic to handle.

 

Man, just hone that sucker.