HI,
I have a 2007 SL550 with the dreaded central vacuum pump issue where it gets wet and get destroyed. I took the part out and played around with it to see if it works. The motor still works, but the impeller was destroyed. I can't get the motor to work through the PC board though so that must be toast. I'm looking for a replacement, but most of the ones I see on ebay are around $800. It looks like ones from W220 models use the same pump, but has anybody attempted to do this before?

 

as long as the part # matches. those can be rebuilt for about half