Hey guys,

I have a 1990 Firebird that could use a good cleaning under the hood. I was just curious as to what the best way to clean the engine bay would be. I don’t know if spraying water on the engine components could cause damage. Thank you in advance

 

I've always put plastic grocery bags over the alternator, distributor and battery, and then sprayed away! ...and in truth, those items can get wet too, but it's always made me feel a little more comfortable.

 

I do this plus check all the underhood wiring for anything exposed. Personally, I vacuum everything first then remove the battery to clean under there anyway.

 

Yes, water can get past valve cover grommets and inside electrical connectors. I've never washed the engine in any car I've owned. Problem avoided. I have wiped things with a cloth when I wanted to clean up something.

If you really really want to clean then wipe and scrub by hand and rinse softly with a minimal waterfall from a hose, don't spray indiscriminately. You can get alternator wet but go for a drive when you're done to dry it out. Letting the alternator sit wet for a while can cause the rotor to seize to the stator when rust bonds things together.

 

Best way to clean an engine is to tear it apart, and clean the parts one by one. Take off all the accessories, the valve covers, fuel delivery system and intake manifold. then you'll have access to most all you need. while your at it, remove the radiator.

Also give you a chance to change leaky gaskets and plug the old oil leak hole at the front of the block. Lots of work, but a thing of beauty when your done. Just did this to my 545 over the course of the last few months this year. When you start messing around when anything that could get into the engine oil, make sure to change the oil when your all done. fire up the engine, let it run a few minutes. then change the oil.

 

Used to pop the hood at car wash weekly to give the engine and compartment a good blast and scrubbing with the wash mit. Don't drive it as much these days but still do now and then.

 

Yes, when I wash my cars by hand (doesn't happen as often as it used to) I always pop the hood, rinse it with light pressure (we're talking garden hose, and a modest pressure at that...no power washing or high pressure car wash stuff here). Wash it down by hand with a dedicated mitt, then rinse again. I dry some items by hand, for instance on the T/A, the air cleaner lid.