Hey guys! I haven't been active in a while, been lurking some when I get time, but don't contribute much, because I don't know that much. (Haha)
Anyway, I'm back to working on my '51 2-ton, and I'm rebuilding leaky wheel cylinders. I'm keeping the brake system stock, and was wondering if while I'm at it, I should rebuild the master cylinder and Hydro-Vac? Neither are leaking as far as I can see, but I thought it may be good preventive maintenance. What do you guys think?
I don't know much about the Hydro-Vac, other than I guess it's just a brake booster? When that goes bad, what will the symptoms be?

When driving the truck (before the wheel cylinders started leaking) the first pump on the brake pedal would go to the floor, and the second pump would have pressure and good braking action. What does that sound like a symptom of?
Thanks!


1951 Chevrolet 6400