[Ian Crawford]

Removing Engine Sludge. When dismantling an old or used engine, to be repaired or worked on, the accumulated sludge and combustion by products inside the engine are always a problem to clean at home.
Most solvents and cleaning products do not work well and it is a laborious uninviting job to get the professional result most of us would like.

What works for me:
Home Oven cleaner spray, available at your supermarket.
Be sure to observe ALL the safety precautions listed on the can. Best to use outdoors or in a well ventilated area and wearing gloves and goggles.
I am in no way responsible for your safety of how you may choose to use these products.

There are generally two types available, aluminum safe and non-aluminum safe. The non-aluminum safe will dull polished aluminum but not much else in the short length of the term used and is generally more potent.

How to use: Leave the engine mostly assembled in sub-assemblies i.e. Short engine, cylinder heads complete etc.

Spray the oven cleaner everywhere there is sludge or dirt, in the crankcase, cylinder head ports and valve springs.
Leave for 20-30 minutes and hose of with water. Dry the parts with compressed air and leave in the sun. Remove the crankshaft and camshaft if installed, dry and inhibit all parts with corrosion preventative. For heavily soiled engines, a few applications may be necessary. Most engines will require 2-3 cans of spray. Good luck and enjoy.