To steam clean an automotive engine, first prepare the engine by allowing it to reach a proper temperature, then cover all sensitive components. Next, clean the engine using a degreaser and steam-cleaning equipment. Dry off the engine to finish the job.
- Prepare the engine for cleaning
Let the engine sit overnight to make sure it is cool. However, if instructions for the degreaser recommend a warm engine, let the engine sit for a least two hours. Next, disconnect the battery, remove it, or cover it well. Using plastic baggies or aluminum foil, cover all sensitive wiring, sensors, the alternator, the engine's air intake, the fuse box and cable junctions.
- Clean the engine
Begin by using a brush to remove loose dirt and debris. Then, using the steam-cleaning equipment, clean under the hood of the car to remove dirt and grease. Next, spray down the engine bay with a non-petroleum based degreaser. Following the directions of the degreaser, allow it to sit for the specified amount of time, then use the steam cleaning equipment to rinse off the engine bay. For very dirty engines, apply multiple coats of the degreaser.
- Tidy up the engine
Remove the plastic baggies or aluminum foil used to cover the engine's delicate parts, and reinstall the battery. Dry the engine of any excess water by wiping it up and using a can of compressed air on the crevices. Finally, start the engine, and allow it to dry itself thoroughly.