What is the best way to clean the engine for painting? I have used Naptha to clean the oil off various parts but it seems to leave some kind of film that paint may not stick to.

 

Good old fashioned liquid soap and water. I also go over the area once dry with alcohol in a spray bottle. Then use some air pressure to blow dry.

 

After cleaning the engine with your choice of cleaner use 3m wax and grease remover. This is used by paint shops as the final prep before painting. It removes any wax, grease, and other residue from othe cleaners. It has a slower evaporation rate than naphtha, acetone, and thinners. I put the wax and grease remover in a spray bottle soak the engine down and start wiping, continue reapplying until your rag remains clean.

 

DAWN dish soap and very hot water .

 

I will second that. If Dawn can clean up baked on Lagasna it can sure clean your engine and Dawn does not leave any soap residue.

 

You haven't seen my wifes lasagne, and her name is Dawn. Is the motor a used drop in, assembled or in parts?

 

I cleaned it with spray degreaser to get the heavy stuff, then hit it with brake cleaner before painting. Seemed to work fine.

 

Brake clean is a very good idea.

 

I used to use TSP quite a bit with good results. A little elbow grease too. I think dawn is probably the best though. I have a small jug by the sink to clean up with after wrenchin'.