Brakes from HELL!!

[Huck]

OK, I've owned this Blazer about 3 years and the brakes have sucked from day one. I've replaced the rear drums, shoes, and wheel cylinders. I replaced the master cylinder twice. I even tried a 3/4 ton Booster. Still sucks.
Yesterday I drive down the road and have to hit the brakes and only the right rear locks up--no braking power on the front wheels. Tried it a second time--same results. Have had them bled so many times it needs bandaids.
I suspect the proportioning valve but before I dump another $80. into this pos--would like some very knowledgeable, highly experineced help with a process to resolve this PITA~~! Anyone really know 72 Braking system????

[truckdude239]

replace all rubber lines thoughy bleed the system i replaced my hard lines with replacements from www.inlinetube.com. maded a difference. sounds like it time to just rebuild the hold system new rubber line, calpiers, pro vavle, mc. it sound slike the fronts aren't getting any fuild to them

[BOSS]

Subscribing so i can maybe find out about mine also.I would guess the valve but then again sometimes mine feel spongy and other times they will just about throw you threw the window.I am like you i think i have tried about everything but i cant keep buying new stuff over and over again.

[68C15]

no front brakes---combination valve (prop valve) ?
one rear brake---stuck wheel cylinder, severely out of adjustment?

time to spend some money by doing the whole shebang. EVERYTHING!!

[1969K10]

On your "combination" valve, there should be a pin that barely sticks out. if it sticks out a lot, or is sucked in, it means it has shut off the fluid flow to the front or back...
When you redid the back brackes, did you turn the star adjuster in until you could just barely hear the pads rubbing the drums? if not, you might have too much movement in the rear shoes for the brakes system to build up enough pressure to operate.
replace the rubber portions of the brake system!
my '72 had a spot in the brake line that didn't actually leak, but was so thin that when i had someone push on the pedal, i could watch the fluid weep thru the brake line. it never dripped, but the line would get a shiny wet look to it when there was pressure applied. needless to say, replacing that section when a long way in how my brakes reacted.
Good luck

[junkyardjohn]

Hi Warren... I Had Trouble With The Brakes On My 71 Blazer After Replacing The Front Rotors & Pads. I Never Could Get Them To Bleed Right.?(i Pumped About 2 1/2 Quarts Of Fluid Thru Them) They Always Felt Spongy & My Pedel Went To An Inch From The Floor. Replacing The Rear Wheel Cylinders Took Care Of The Problem. John

[67ChevyRedneck]

Does it get driven a lot? "sitting" is bad for brake systems Pop the top on the MS and see if the fluid levels have dropped any. If your truck has the original lines it's possible they have been collecting gunk on the inside of them over the years and are starting to plug? My guess would be a plugged/dysfunctional prop valve as well.

Just tossin some ideas out there.

[low'n slow]

Ask around for someone with a power bleeder. When I was in Utah the local Big O tire store had one. It does a great job making sure there are no air pockets in the lines. It may also clear any blockages you have.

Doug

[A.P.]

Try some info from this site. Hope it helps you, it sure helped me.
http://www.classicperform.com/TechBo...tm#tshootbleed