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newb brake bleed question

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89k5350

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so now ive done all new front brakes and rear lines and rear drum brakes are like new besides wheel cylinders. the rear bleeder screws are rusted/stripped to all hell and I was informed by my auto teacher that I could bleed them from the lines since theyre new. he said that the only air there will be is just in the wheel cylinder because the line is lower down than the bleeder screw. so I did a normal pump and hold brake and just cracked the lines till fluid came out on every wheel. and I basically get no brake pedal till its too the floor then I have 4 good brakes but still that's when the pedals at the floor. they also don't build up like it would if there was air in the system. and when I pinch the rear brake hose to just block off the two wheels then the pedal builds up fine and stiff. so does this mean there is too much clearance in the rear drums and need to adjust the rear starwheel adjuster?
 
Brakes could be out of adjustment, but this will usually give you a low pedal, not all the way to the floor.

Replace the wheel cylinders. They're cheap. Bleed them properly. I bet your problem will go away.
 
I have new ones but I cant fit my cut off wheel behind the backing plate to cut the heads of the bolts off cause theyre rusted and stripped. that's the whole reason I tried bleeding through the lines.
 
agreed w/ changing the wheel cyl while your at this point...if you have new lines already on there, get the new wheel cyl and bleeders screws as well....then use some antiseize on the bleeder screws/lines threads.
You may need to push more fluid through the system than you have as well...also check the shoes to see if there is any drag on them, if not adjust the star washer out til the start to touch then back it off for free turning drums, then bleed the system.
 
I wanted too replace them at the start but I got no room to even fit my 3 in cut off wheel in there for the bolts
 
Welcome to the world of auto mechanics..... "figuring it out"

I come across things all the time where I think to myself, how am I going to get this off/out/on,, whatever. Just work at it, you'll figure it out. :D
 
I have cut wheel cyclinders apart on the drum side. Just cut off in chunks and eventually it will fall off. Install new wheel cylinders. The rest of the work is useless without them.

And get a new auto teacher.
 
Way out of adjustment rear brakes will cause low pedal. So, if you need to run it now, do the adjustment.
But, if it has some time off, and you are doing work on it, now is the time to replace the cylinders.

Got a drill? Look at the drum side of the cylinders. On most of them, you will see the humps where the bolts are. You can carefully start drilling a hole with a small bit directly into the end of the bolts.
Use lube, and drill slowly until you hit the bolts.
Then just use bigger and bigger drill bits until you get up to the size of the bolts. At that point, you can spray some Kroil or something like it in around the threads and let it soak.

Maybe with some heat.
At that point, you can punch and drill a small starter hole into the end of the bolt, and then put a bit in that will bind as it starts, and many times the bolt will back right out.

Otherwise, you can drill out the bolt, or just use bigger and bigger bits on the cylinder until there is only a small amount of cast iron around the bolts.
Then a quick whack with a hammer and it should fall right off.
 
A sharp cold chisel fits in there and a few whacks with a hammer will shear off the bolt heads like peanut brittle..air chisel or cutting torch works good also!...new wheel cylinders are probably 10-15 bucks each,well worth doing,forget screwing with the rusted bleeder screws..you should be able to install them without pulling the shoes off too,I did both rears on my 82 in about 20 minutes...
 
I completely agree with you guys that its best to just change the wheel cylinders, I do have new ones. but im just trying to get a stiff pedal to pass inspection temporaily. at school someone told me about how if you frive in reverse and jam on the brakes it adjusts them for you?
 
89k5350 said:
I was informed by my auto teacher that I could bleed them from the lines since theyre new. he said that the only air there will be is just in the wheel cylinder because the line is lower down than the bleeder
Click to expand...

There is your problem. Any air in the system will compress and give a soft pedal. The bleeders are positioned at the top for a reason. It sounds to me like you still have air in the lines. Use a small bolt extractor or vise grips to remove the old bleeder (it already has a hole in the middle). Get some new bleeder screws off the "Help" shelf ($3). Bleed them the right way. And they will work properly. Are your wheel cylinders even leaking?
 
Unless we all just completely misinterpreted your problem, it's not your adjustment. You can adjust the snot out of them and you'll still have a soft pedal because AIR compresses. If there was no air in the line, your pedal may be a little low, but it would still be firm.

It may not be easy to get the wheel cylinders off, but you should go ahead and commit. You'll get them off eventually. You can do as AR K5 said and just try to replace the bleeders to get by. But even if they're not leaking, I'd be getting those things off my truck. If you can't get them off easily in your driveway/garage, imagine how pissed you'd be if you were stuck on the side of the road/trail trying to get them off b/c you put it off.

Lastly, for your sake and those around you, fix em right. Brakes are not an area where it is acceptable to take short cuts.
 
rebelgregory said:
But even if they're not leaking, I'd be getting those things off my truck.
Click to expand...

Why? He didn't say anything that indicates they are bad, just that the bolts holding them on are rusty. If they aren't leaking and they work, that means they are not broken. If air is the problem, new wheel cylinders won't help until he can get it out. If the wheel cylinders start leaking he can rebuild them. Why waste money and effort replacing parts that aren't bad when you can do it right with good information. The bleeders are put where they are put for a reason, thats why you have to buy a left and a right brake caliper. Even if you can make them fit on either side, you can't bleed them properly from the bottom.
 
If you're trying to say he doesn't have to replace the actual wheel cylinder, I agree. Hence the "You can do as AR K5 said..." part. He said he already has new WCs as part of his original brake job, just hasn't put them on b/c of the bolts and the bleeder is stuck. If it was mine, I would finish the job, not leave it with stripped bolts. Hence, the part you quoted. Yes, they are rebuildable, but A) they're cheap B) He already has new ones C) you still have to get them OFF to hone it properly. I stand by my recommendation - replace em.

I don't really follow the part about the bleeders being down. Not sure what that was in response to.
 
Ok he already has new wheel cylinders, my bad.

rebelgregory said:
I don't really follow the part about the bleeders being down. Not sure what that was in response to.
Click to expand...

I was explaining why bleeding from the line isn't working, the air is trapped at the high point and won't travel back out to where the line connects. The part about calipers was just another example you can go look at to see how it works and why.

On another somewhat related note.
I bough a 14 bolt with the disc brake conversion installed on the bottom, I'm guessing he couldn't bleed the brakes. Not that it would have done much good because 3 out of 4 of the slider pins were broken from hitting rocks.
 
My rear calipers are flipped (bleeders down)and mounted above the axle for this reason. Also puts my e-brake cable in a better config (above the axle) and yes, it takes a lot of extra work to bleed em.

2013-07-01 15.47.55.jpg
 
so just too clarify the problem. when I krimp the rear brake hose that gives fluid to the rear wheels I have a good pedal. as soon as I unblock the line the pedal goes right to the floor but when it gets too the floor all brakes work fine. the pedal does not pump up like it would if it had air in the system. this is after I bleed from the rear lines for ****s and giggles. the rear cylinders work fine. just as soon as that rear hose on the axle is blocked it gets a good pedal.
 
diesel4me said:
A sharp cold chisel fits in there and a few whacks with a hammer will shear off the bolt heads like peanut brittle..air chisel or cutting torch works good also!...new wheel cylinders are probably 10-15 bucks each,well worth doing,forget screwing with the rusted bleeder screws..you should be able to install them without pulling the shoes off too,I did both rears on my 82 in about 20 minutes...
Click to expand...

I agree torch is what I would use but be careful there's gas lines and a tank
 
89k5350 said:
so just too clarify the problem. when I krimp the rear brake hose that gives fluid to the rear wheels I have a good pedal. as soon as I unblock the line the pedal goes right to the floor but when it gets too the floor all brakes work fine. the pedal does not pump up like it would if it had air in the system. this is after I bleed from the rear lines for ****s and giggles. the rear cylinders work fine. just as soon as that rear hose on the axle is blocked it gets a good pedal.
Click to expand...

As already said, that means you either don't have the rear shoes adjusted correctly or air is still in the lines. The shoes need to be adjusted by turning the adjustment screw through the hole in the drum until there is slight drag. Slamming on the brakes in reverse is not the correct way of doing it. The way I bleed my brakes is by using a power bleeder that I built, makes for an easy one person job. Here are some examples of power bleeders that are similar to what I made:
http://www.arkansaspontiacs.org/techstories/bleeder story.htm
http://www.bmw-m.net/TechProc/bleeder.htm
http://coloradok5.com/forums/showthread.php?t=138124&highlight=garden+sprayer+bleeder
 
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