Forget the pressure washer.  A degreaser engine spray and a garden
hose (without a high-pressure nozzle) will work well.   Towel dry as
many areas as possible and run the engine for 10 minutes to help dry
all the parts.

I've done it many times using the exact same method.
Even with the degreaser, I still scrubbed a few parts to get them
clean before rinsing.
Just don't get the tip of the nozzel too close to the engine...
stand back a few feet.
If you're using a commercial washer, make sure it has a
fan-spray nozzel attached.
You're just rinsing, not blasting...you'll remove paint.

As noted by Phisherman; a garden hose will also work just fine.

Some commercial washers have a hot water option.

I would say using the pressure washer or degreaser should both be avoided if possible.
Simple Green works pretty good but  try to avoid even getting water on anything
you don't have to. Like the electrical components or belts for example.

Be sure to disconnect the battery too.

Dan