question on brakes

[va_tlc]

hopefully someone will have the answer. 72 cab.. 70 4x4 frame. drums all the way round. put new shoes on all 4 new wheel cyl all 4. didnt turn drums pretty smooth. new master cyl. 70 model. the por valve i have is the 1 that was on the 72 cab the wire hooks up under side of the valve. my problem is when ya hit the brakes it pulls real bad to the left. think it could still have air in lines? or wrong porp valve? i did put new adjusters on too. any thoughts? thanks n advance

[hootlube]

Did you crank the adjusters out when you put the drums back on? I usually will put the drum on, if it goes on easily, I take it back off and move the star wheel a couple of turns until the drum kind of "fights" going back on. That way, I know the adjustment is pretty close to tight. Other guys probably know an easier way...

[va_tlc]

well we put the drums back on , then spun the hub while cranking the adjusters to barley rub the drum? im thinkin we still have air in there. someone said to gravity bleed em. anyone ever done this? thnks hootlube

[ABLAZN]

Your prop valve adjust the pressure from front to rear and has nothing to do with side to side. You should use the prop valve from the 1970 since it is meant for a drum/drum set up. They run a different pressure ratio from front to rear then the disc/drum valve that came on the 1972. Your problem is most likely as mentioned, that one side is adjusted tighter then the other. I just back my adjusters to were the drum slides on, then start moving the star wheel until there is some resistance while I turn the drum. Do this on both side so that the resistance feels the same on both sides. One other thing to look at is make sure that you did not mix up the shoes when they were put on. Many sets have a bigger and smaller lining per wheel, so it is possible to put on two bigger linings on one wheel and get a pull also. I am sure that is not the case, but something to check out just in case.

[northerngmc]

I think I am overstating the obvious, but are the drums and brake shoes clean? I have seen where a wheel seal goes and oil gets on the drum and shoe and causes that brake to grab.

[va_tlc]

yea shoes are clean new wheel cyl and all. i belive there adjust properly also, gonna try the gravity bleed this week, just drove it to aligment shop and no further hiting the brakes was just to scary so i have to get this fixed before i drive it again, hopefully theres still air in it

[hootlube]

EZ way to bleed one man... hook a piece of rubber hose to the bleeder (open the bleeder first, and make sure you have plenty of fluid in the master), and stick the other end of the hose in a bottle with some brake fluid already in it. Pump slowly, the bubbles will come out the tube, into the bottle; when it sucks back in as you release the pedal, it will get fluid. BUT... you'll need a bunch of fluid, and you'll have to keep priming the master cylinder. Best if two people do a bleed...

[va_tlc]

well bleed em again today. got the pulling to just about to stop.. but still have to pump the pedal for good brakes?? any more ideas? a friend thinks he knows where i can get disk front end at. so i belive if that comes thru ill just swap them over to power disk. gotta be better than standing up in the seat lol

[Longhorn Man]

when you pump and hold, does the pedal stay firm, or does it sink down after a min or so?
If it's firm, you need to adjust the shoes up... if it goes soft, you still have air.

[oldgold70c10]

If you have to pump the pedal, then you've got either air in the lines or your shoes aren't adjusted correctly. Go to the auto parts store and get one of those little vacuum pumps, best $30 you'll spend on a tool, and use it to bleed the brakes. Did you replace the hoses? Might waht to check for leaks on those. When you are sure you don't have air in the system, make several hard stops in reverse, pumping the brakes as you do. If all is working right, and you put the adjusters in correctly (they are a definite left-right, as the ones on one side have an opposite thread) then you should have a good, firm pedal.

Manual drums with new shoes when adjusted right really do stop well, you will be suprised.

[msgross]

dude, I would just switch to a newer front axle. I am replacing mine with a Corp 10bolt (identical to Dana44?) from an 82 K-10. What gears do you have? I have a few axles (3.08, 3.07) but no hubs for ya. You could swap your gears in but you have to be able to set them up, easier to find a donor axles with gears already set. For a few bills you could have a disc setup and be rolling in a day!

Or I have a distro valve (not prop valve) which is what you need to stay with drums.

[northerngmc]

Any luck yet?

[va_tlc]

yea northern. took it out to a friend and he saw that the new adjusters i put in was adjusted all the way out. he brought em back in and waaa laaa instant brakes... but said my drums are shot. cause like someone had mentioned i ran it in reverse and hit the brakes to get em to self adjust on there own. so my new drums will be in fri hopefully, was gonna switch to disk , but since iv replaced everything for the drums ill just stay with drums for now thanks for everyones help, tony