Hello ,
I rebuilt my power steering pump because it had a leak from the backside of the reservoir. Everything went well but the vanes did fall out and I put them in one by one checking for best fit.I used Prestone power steering fluid but there's absolutely no power assist from the pump.I am really stumped.Many members did this job with no ill effects.Please could anyone chime in?Once the 3 plates fell out and I put them in according to the indentations marks from the wear and tear.It is a Vickers pump from a 1989 300E.Before the rebuild it worked perfectly except for the reservoir leak.Before the rebuild I always used the MB power steering fluid.I have checked the forum up and down but couldn't find a exploded view of the Vicker's pump.I would like to eliminate the idea that I put the 3 plates back incorrectly.I did change the hose for the return line because it didn't look too well and the new hose has a smaller diameter than the previous hose.Could that be the cause?I bled the air by lifting front of car and turning left/right about 10 times but even then I could tell that there was no power assist from the pump.

Check to see that all the square edges of each paddle fit towards the center of the daisy wheel. The outer edges that run up against the eccentric chamber and build pressure need to be the smooth, rounded part. So the smooth, rounded part goes to the outside. Also, check the arrows stamped on the parts and make sure that they are all pointing in the same direction.

Did you leave any rubber or plastic protective caps on the new hose or pump that might have worked its way into the system and clogged it?. You would probably find it at the entry to the gear box if you did.

Sometimes, the control valves have been known to stick and all it takes is to push it in and out a few times with an ice pick to get it to work.

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Thanks for your reply emerydc8. The leaks have stopped - but unfortunately so has the pump. Yes I did put the vanes with the smooth side facing out.
The return line which I changed didn't have a protective cap. It was just a 3 ft hose (which I cut to same lenght as original hose) but it has a smaller ID.I will try try to switch the hose to the original and see if that makes a difference and post the results. Is the control valve the black button at the end inside the housing? I know there's a black button that seems to be spring loaded which works without any binding. I don't think that I looked for any arrows because I didn't know that there were any. That still leaves the option open that I installed the cartridge in the wrong order. A kingdom for a exploded view of the Vickers pump. I have searched the web and other forums even in Germany but no luck. I wish I could take the pump out again today but my index finger is swollen after the knife cut when removing the clip from impeller yesterday. I have removed the pump a total of 2 times now. I will check for the arrows. Thanks again

It looks like you have found the spring-loaded control valve. Be careful when you push in on it because the retaining clip can easily come undone.

Attached is a diagram of the arrow on the cam insert. I think it might be idiot-proof anyway, but just in case, you may want to see if you can find the arrow on yours. The pressure plate also has to go on with the ground face pointing towards the cam insert.

I know what you mean about cutting yourself getting the radial shaft retaining clip off. It's hard to get off and it seems that the best way to do it is with a small screwdriver, rather than a c-clip removal tool.

If you need the whole 46-page job, let me know. It was too large to post it here.

Attached Files

Pages from 46-0730.pdf (41.5 KB, 164 views)

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles

Emerydc8 you have a friend for life! I used your PDF and compared it to how I reassembled the pump. Turns out that I didn't align the arrow. On my cam insert there's not exactly a clean machine pressed arrow but a ">" looking thing that I always thought was a scratch. I aligned the arrow and reinstalled pump and VOILA ! Thank you so much for the attachment. Now my steering is leak-free and soft. This forum is a life saver.

You're welcome. I'm glad you were able to fix it.

__________________
1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles