Pressure Bleeding won't "kill your Master Cylinder". In the earlier thread mentioned, I posted the following...

"And rest easy about your MC. You didnt "toast" it. It won't "blow"at 15psi (the Volvo shop manual says 29 to 44 psi on the bleeder), and nothing moves internally when you pressure bleed—except the fluid of course."

I doubt you did any harm to the MC. But what bleeding sequence did you use. And did the shop that replaced your wheel bearings remove the calipers (i.e. open the lines)?

They shouldn't have, but I ask since that seems to be when the trouble started. You describe the perfect system, but with a problem. So it's hard to know where to begin.

--
Bruce Young,
'93 940-NA (current)
'80 GLE V8 (Sold 5/03)
'83 Turbo 245
'76 244 (lasted only 255,000 miles)
73 142 (98K)
'71 144 (track modified--crusher bound)
New 144 from '67 to '78
Used '62 122 from '63 to '67