I just finished an engine swap in our '91 240. Now there is a vibration when turning the steering wheel while the engine is running. It seems worse at different steering wheel positions. Also, it seems to be putting a load on the engine when the vibration occurs.

Searching on the web, there seems to be a TSB for the bleeding procedure for the CAM racks. From reading the TSB, the problem I'm having seems to be due to air in the power steering system. The steps in the TSB are supposed to be performed prior to starting the engine. Unfortunately, I have already started the engine and most likely foamed whatever air is in the system.

Does anyone out there have any idea how I can bleed it now that I have already foamed up the system?

 

I think I would get some power steering fluid (or just use ATF, thats what I use), and do the bleed. if/when foam comes up in the power steering reservoir, suck it out with a turkey baster (or I use my topsider oil changer), replace with fresh ATF, and repeat til its clean?

is this the TSB info you saw?
Steering:

instead of disconnecting the tie rods, you could just jack the front of the car up and put it on jack stands. and I might just remove the belt on the power steering pump, and put a small rubber wheel on an variable speed electric drill and use that to spin the PS pump instead of straining your starter motor...

 

Yeah, the TSB you show is essentially the same. I pulled up a PDF of what looked to be a scan of a paper copy of the TSB that came out in 89. Looking at my reservoir, I don't see any foam though. My car has the type of power steering pump with the reservoir bolted to the inner part of the fender next to where the 25 amp fuse is. Looking in there, I see no foam or bubbles whatsoever.

I have left it overnight turned all the way to the left and did the same all the way to the right hoping that the air would come out but it hasn't seemed to help.

I'm tempted to drain the entire system and start over but I'm not sure how I can drain the entire rack. Any other suggestions?

 

I think I'd put the front end on jack stands, start the engine, leave it idling, and slowly turn the wheel back and forth stop to stop to stop, to pump stuff around, periodically checking the reservoir. if anything bubbles up, shut off the engine, turkey-baster out as much as you can, refill with fresh, restart the engine, and repeat the stop-to-stop. thats how I changed the old PS fluid on a couple of mine.

 

I did the procedure as you stated and indeed, I did get a few bubbles the first time through. After second and third, no more bubbles. Gave me something to do while I was flushing the engine.

After bleeding, the shudder seems gone. Thanks for your help.