Looking for advice on what chemicals to use to clean my engine bay. It is very dirty with dirt, grime, oil build up, etc. not looking to use a pressure washer but rather do it by hand. I have no issue with that. Just need to find some good chemicals to do it. I'm also looking to paint the top of my intake manifold and a few other pieces as I no longer have my engine cover on due to the spacers. I know they say tire cleaner for the rubber hoses. Also has anyone painted their intake manifold or any other parts under the hood? Just looking for ideas.
Kudos for avoiding the pressure sprayer and doing it by hand.
I would start with ordinary car wash, or maybe some dish/kitchen soap. After that, there are products such as Super Clean and Purple Power Degreaser, both I've purchased at Walmart. These are both concentrated detergents so it's best to wear some latex or nitrile gloves. I've used them to clean many of the pieces from underhood, altho I usually remove the pieces to clean them.
Also, go on a scavenging hunt for small brushes. You can't have too many different shapes and sizes. Toothbrushes and Q-tips are a good start, but there are many others that can be very handy. Some towns have specialty shops that carry a variety of cleaning tools - the Container Store comes to mind. Baby stores have bottle brushes which are helpful, too.
Lastly, a pair of very long needle nose pliers are great for clutching a wad of paper towel for cleaning and for swabbing up excess liquid. An air hose can be a great tool as well, but it can also blow liquid onto stuff you don't want to get wet.
After these detergents, you will start getting into acids and/or caustic cleaners (such as CLR) which can be harmful to many surfaces, so I recommend avoiding them.