How do you clean your engine bay?
 

I finally decided to give my engine bay a "deep clean." I covered the alternator as best I could with a plastic bag, sprayed everything in Simple Green (let it sit for a couple minutes), and then lightly sprayed it down with a hose until all of the Simple Green was gone. I was amazed at how clean it was after just one clean job.



At first I was hesitant to use the hose, but many people seem to do it without issue (after all the engine gets soaking wet during heavy rain anyways). How do you clean yours?

Engine degreaser (if it needs it) and pressure washer. Done it that way for 40 years now.

I just use soap. Maybe degreaser (which is strong soap). I actually mix up a batch of strong soap water for the wheels, wheel well, and use it (and the same brushes) for the underhood work. Same brushes that get through the spokes, around the calipers, etc, are great for getting at the engine. Just use a hose, no pressure.

I wouldnt worry a bit about the alternator- its made to handle water.

Is there really anything under that hood that 100% cannot get wet?

Do you remove the vanity engine cover and spray under there as well?

Do you wipe the whole bay down after spraying or just let it air dry?

How long after you spray with water do you wait until you can run the engine?

AFAIK, the inside of the engine compartment is designed to get wet.

All connecrtors have *some* level of water-resistance rating, IPxx, etc.

I usually just let it air dry. If I will be detailing it, maybe I use an electric leaf blower to speed it up.

I will start it immediately, or whenever I need to. No special considerations.

YMMV

I should have added if you use pressure do not spray electrical connections or other water sensitive areas with it. :thumbup: Having said that, almost all of the engine bay is designed to get wet, including the alternator.

warm, not hot engine.
Simple green, gentle but firm warm water rinse.
30 years, 6 times a year, per car, 3 in the fleet currently.
I have had two issues. Datsun 280zx cracked distributor that i didn't know about.
Brothers BMW 325ix didn't like getting wet.

Good comments about the alternator. I won't worry about covering it up next time. There's a few areas I need to break out a brush for (driver side timing cover).

I need to take the vent covers over the brake fluid reservoir and cabin air intakes out and clean those deep wells under them. They look really bad.

I vacuumed mine out the other day when I did my cabin air filters. Still could use a good washing though. It’s amazibg how much debris can get stuck down there.