I have my engine tore apart and am trying to clean it up for paint. I have tried a bunch of different methods (engine degreaser, carb cleaner, wire wheels, etc.) I am just wondering what you guys have found to be the best way to clean up greasy housings, irons, etc. for paint.

 

Wash with solvent, media blast.

 

If you can't media blast, a parts washer and then a wire wheel on a drill.

 

One trick I've used successfully on rough castings is to heat them after the initial cleaning with solvent.
After getting all the crud you can off, place in an oven set to low- 100-125°- for an hour or so, then reclean and dry.

This seems to help get the "pores" cleaner and prevents leftover oil from seeping up under the paint when the engine is run up to temp.

 

I've found that any oil/carbon that is missed in the solvent bath winds up getting spread over the entire part by a wire wheel.

The dishwasher is an excellent and easy parts washer, but make sure to taker them out before the drying cycle because iron based parts will quickly rust.

 

Ah, forgot about the dishwasher! I've used that one in the past but make sure the female of the house is gone when you do it.

I generally wash in the parts washer, then rinse in the sink/bathtub with super clean, then brake clean, then compressed air. Then do any porting, and repeat the process.