If you attempt to clean your engine, be warned, this is where
things can go wrong in a big way. Engines and water don't mix well, so only
attempt to clean your engine if you feel you must, and at your own risk.
Firstly try to keep away from electrical parts as
much as possible (alternators etc). Secondly leave the engine running as the
heat from the engine helps to keep the engine dry. You will need a strong
cleaning agent, such as traffic film remover (T.F.R.). Spray the T.F.R. over the
engine and allow to soak into the grease and oil. Then wash off the T.F.R. and
the dirt goes with it. This is where a hot water steamer really helps, but it's
not absolutely necessary as a cold one works perfectly well, it's just a little
harder.
When the engine is washed off allow to dry, keep
the engine running to aid drying. Then when dry and cooled down you can paint
the engine with engine lacquer, if required, to finish off the job.