Best way to bleed entire Power Steering system?
 

Starting a new thread so things don't get mixed up.

I have a squeal coming from my new power steering pump on my 300TE...

The factory manual makes no mention of bleeding the system. Can someone tell me the best way to make sure my issues aren't simply trapped air?

With the engine running turn the steering wheel from lock to lock several times. Doing this will bleed any air from the system. Make sure the system is filled with the proper fluid. Squeals normally come from improperly tightened belts (slipping belt) or fluid/oil on the belt itself.

I've never found the need to do the engine running thing.

Just fill the system. Put the front wheels on slip plates or just raise the front end. Turn the steering wheel from lock to lock. Check fluid level as you go.

If you get weird noises with out the engine running then I guess it would be easier to track them down with out that extra background noise.

air entrapment would manifest itself as a moaning sound from the power steering pump specially when the control valve operates (steering being turned)

a squeal would be more a loose belt or severely worn out fluid in it in arctic winter causing the pump to lock or a fully clogged filter in the steering oil reservoir

I dont think I have seen an air trapped system in a W124, seen quite a few on W210 (and other rack model MB)

I use the GM procedure to remove air from the rack and pinion MB cars, I apply a vacuum of 20 inches to the pump reservoir and pull out the air, cycling the steering lock to lock with engine off and tires in the air pulls out the air bubbles.