Any tips to clean the engine? I have my system down for washing the outside but have never really washed and engine/engine bay.

 

good overview

 

Since new, I power wash my GX460 engine compartment every 8-odd months to keep it looking close to brand new ... so only use the Rinse setting using warm water ... soap or cleaners are not necessary. When using a power washer, just avoid direct blasts to electrical connectors and there will be no issues ... modern connectors are water sealed and can prevent water from causing electrical problems.

Many engine cleaners work great ... but work great because they have caustic agents to cut thru heavy build-up. Yes, the engine compartment will be clean, but these cleaners will cause and accelerate corrosion, specifically to aluminum parts.

For my older vehicles, I use a motorcycle cleaner called S-100 Total Cycle Cleaner ... amazing stuff used widely in Europe by motorcycle zealots who need a product that cleans every nook and cranny without the need for meticulous scrubbing. Simply spray on and rinse off with ... amazing results with absolutely no compromise to any surface or material. Trust me ... it's (relatively) expensive but worth its weight in gold if you care about your vehicle. I use this every other time in the engine compartment.

 

also if you have a leaf blower that works well to get the water out of the areas where a rag or some other item can't reach...
(it's how I dry my paint to avoid swirl marks and water spots...)

 

That's how I dry my motorcycle !