1988 conti sig ser rear brakes

[kaukasion]

i just bought this car for 500 bux
the power brakes dont work and light is on at the dash
the previous owner told me that sometimes but rarely the power brakes will work
and that in a previous encounter at changing the rear pads that he had a heck of a time getting the piston back into the caliper

should i assume that this person was an idiot and did not rotate the piston while putting it back into the caliper
and also that he couldnt get the rear brakes to bleed since this occasion

would forcing it in ruin the caliper?
would ruined rear calipers cause the entire power braking system to fail?

please offer any advice you can or any trouble shooting advice, that could narrow down the problem

all help will be greatly appreciated

 

[kaukasion]

also if you have been through a similar problem and are or a mechanic you can contact me more directly at blknght911@insightbb.com

 

[jpappano]

Rear brake lines, the flexible rubber line. IF they have a CLAMP in the middle of them that attaches them to the strut, The clamped area in an older car will "collaspe" under the clamped area and will not let fluid run thru properly, only a dribble of oil will be able to get thru under pressure, hence after you take your foot off the brake, the rear brake pads will stay locked up for 10 minutes or so.. If you loosen the bleeder and you peel doesn't go down easily, Look at the rubber hose as being restricted! I've seen lots of them in the 91 thru 93 Continentals!