I have not recommendations about rebuild, but this seems to be one of the major caveats against using the new DOT5 fluids in Hydrovac systems. Had you sucked all the silicone fluid into the motor, the results might have been rebuilding a lot more than just the Hydrovac unit.
I would like to know who rebuilds these when you find out so I can add that info to my technical tips as this comes up from time to time and I have no ideas.
Thanks
