Hello again, haven't posted in a few years and would like your help: When I parked my 58 spartan 2 years ago, the brakes were working fine, altho the pedal was low and always had been since I rebuilt the entire system 10 years ago. Before pulling the truck out of the shed today I noticed the brake pedal went to the floor - I checked the master cyl and it was empty - yet there were no known prior leaks. Does brake fluid 'evaporate'?, as I can see no evidence of leakage anywhere in the lines or the wheel cylinders. Note that I rebuilt the system completely including resleeving the original 1-1/2" master cyl with new kit and NOS wheel cylinders with modern kits as well as all new lines and hoses....and a remote hydrovac, which was NOS from a 70s/80s era truck. Again, the brakes were functional when last driven. I did notice some possible dried residue on the bottom of the MC, altho not sure what it was, so I removed the MC today and disassembled it and it looks quite clean, just a little rust residue at the push rod end, but no pitting. So, I ask for your ideas, what happened to the brake fluid which was in the master cylinder 2 years ago?
