Switching ABC pump to power steering only pump?
 

've gotten almost 6000 miles out of my ABC pump since switching to Yellowspeed struts on my S600 TT V12. The ABC side leaked, and so it's been running dry. Yesterday, I got the first signs that the power steering side of the pump is about to go south. When the wheel is turned and the car not rolling, I hear a loud groaning and feel vibration. This goes away at speed, but I don't want to be stranded when the pump locks up and breaks the serpentine belt/other expensive things, so I'll stop driving the car until I get this addressed.

I've read that folks are using the power steering only pump from S500/430 V8 Airmatic cars as a replacement, since they are much cheaper. The S500 was available with ABC or Airmatic, but it's a V8 car. As far as I know, the TT V12s were ABC only. My question is whether any different mounts or brackets are needed to make this change, or is it just a simple swap of the pumps? I'd like to have everything I need purchased and staged before I begin the job. Thanks in advance!

I believe the pulley is different

I see that the pulleys are definitely different offset, where the V8 pulley is 'dished' or concave, and the V12 ABC pulley is convex. In cross section, it seems that the negative offset on the V12 pulley is to clear the additional pump, but still maintain the same belt alignment. From the side view, both the pulleys seem to have the same distance from mounting bosses to belt line. If true, and the pulley diameter is the same, it should be a direct swap. Can anyone confirm one way or the other?

The only problem I see is with the 7 ribs belt for S600. You have to get a custom pulley for the 7 ribs. It would be nice to get rid of the tandem pump and don't have to put back the 2 output lines.

I would like to see an actual solution to this problem. Changing it out for another pricey tandem pump and running the abc side dry doesn't seem to be a good solution, as it clearly doesn't last long.....

If you get a custom pulley made, or if you find any other solution, can you please share it with us and/or where to get one made? Thanks.

Tandem pump is only $250 on Rockauto

Is there a banjo bolt that would allow 1 output line?