Any comment, advice or hints, much appreciated.
On my 1991 Masterace,I have a fair amount of juddering on the steering, at low speeds at, or near, full lock. I have checked all the steering joints and everything is OK so, I assume that this has something to do with the power steering side of the rack. Power steering effect is normal at other speeds so I don't suspect the pump. I am changing the fluid as a start and, the pump/belt/drive/fluid level seem to be in good order. From the parts CD I have the part numbers of the various seals but, it would be much appreciated if anyone who has overhauled the rack, and it's hydraulics, would care to comment. Also, is draining the fluid from one of the hose joints an acceptable way to empty the system and, will a straightforward re-fill, through the reservoir, be OK or, is there an air bleed point somewhere on the circuit?
Many thanks in anticipation of any comment.

- (#45) John Davis (Leics), 27 Feb 05 03:00

That sounds like a nasty job, John. I'd pay particular attention to fluid, belt, and pump before delving into the rack though.

Have you looked at the belt whilst turning the steering towards full lock, a slightly slipping belt will give exactly those symptoms, speaking from experience.

My gut feeling is pump, however. Specifically the pressure control valve. If that's sticking, or indeed if the pump is failing to fully exceed it's rated pressure, the valve shuttling to and fro could well cause the same issues.

If you haven't already done so, download the steering chapter of the US Van manual. It's got all you need including the pressure test procedure (if you can acquire the right gauge and fittings...)

- (#45) david miller, 27 Feb 05 05:49

Phew, thank goodness for your comments David. I was all ready for an early morning start tomorrow with a major delve into the steering rack. Your suggestion of the test on the pump/belt at full lock is something I have not tried but, it will be the first operation tomorrow and, a check on the valve.
Thanks for the suggestion re the US Van manual download which, no doubt, will be very helpful

- (#45) John Davis (Leics), 27 Feb 05 09:21

Another comment re David's suggestion on the US Van manual. I had seen references to this in the past but, had never accessed the site. I have now, and it is very useful indeed for many aspects of our vehicle's repair and maintenance. The power steering section has given me all the information which I require and the various manual sections are easy to download and archive onto your PC

- (#45) John Davis (Leics), 28 Feb 05 02:26