ORIGINAL: poorbs
I have a very nice engine that has some varnish cooked onto the head, and wonder what the best way is to remove it without damaging the fins. A very long time ago, I remember helping a friend clean up one of his engines, and the stuff we used was really foul smelling. Any suggestions? Thanks
Cleaners vary in what they are designed for. Depending on what I am cleaning I use automotive carb cleaner, oven cleaner (strong and will clean about anything but use caution), and various other cleaners. Some use anti-freeze by heating the mixtures. If you are in a hurry anti-freeze takes too long and other cleaners will work much quicker - especially automotive carb cleaner.
If there are really thick baked on crud you may want to clean with sand or glass beads. This will affect other surfaces so care has to be taken there. Oven cleaner will clean just about anything, but will also clean your lungs out! We use to clean restaurant grills with a high strength stove/oven cleaner and it was amazing! You could spray it on and within 30 minutes wash it off and the grills shined like you had just purchased them.
Also price is a factor. How much does one want to spend to clean the engine? Steam cleaning is another effective cleaning solution. If you have tons of cash then you could by a hot air boiling tank and clean most anything you like. We used to clean huge engine blocks with our boiling tank. I don't recall the name of the chemical that was in the tank. Something along the lines of varsal or something. You just throw your engine block in there and let it boil overnight. Come in the next day and wash the block, clean with compressed air and it looked like it came out of the factory line
Most of the time you make up the difference of cheap chemicals in labor trying to take tooth brushes and such and whacking away at scrubbing. If you have the time that is OK too, but just not very effecient.