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Discussion Starter · #1 ·
I recently acquired a 87 GMC S15. Terrific shape mechanically with some rust but hey, it's for work. The main prob is the brakes. I think I'm working on just the fronts, which makes stopping very interesting. I can't lock em up at all. So I get them inspected and the shop tells me that the rears need to be rebuilt (long history with the shop so no trust issues). I talk to them and apparently this is not a hard job just a PITA. So I bought new shoes, springs and ebrake cables. Finished the install today but nothing has improved.

When I finished the install I noticed that one side drags a bit more then the other (same as before), adjustment stars all the way in. Now I noticed on the calipers that only one side moves in and out... the other from what I am told won't move until there is enough pressure... BUT it won't move in our out at all. Is this normal or are they seized?

The ebrake won't grab either which tells me that I haven't set them up properly. I'll probably need to pull the line forward abit more.

The master cylinder looks brand new and it's full... I tested the calipers and they move way out when I apply the brakes, but again only on the one side for both.

Any suggestions or things to tweak? I would like to get it on the road this coming week so any help would be greatly appreciated.

G
 

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GMCworktruck said:
When I finished the install I noticed that one side drags a bit more then the other (same as before), adjustment stars all the way in. G
The 'adjusters' should NOT be all the way in. As they get backed out the shoes will spread further apart, putting the shoes closer to the drums. Keep spinning the 'adjuster wheel' out untill the pads drag on the drums. Should be a light friction fit as you slide the drums on.

If the adjusters are way out of wack, your vehicle will typicaly brake for sh!t. Or wont in this case:D :laugh :D
 

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GMCworktruck said:
Now I noticed on the calipers that only one side moves in and out... the other from what I am told won't move until there is enough pressure... BUT it won't move in our out at all. Is this normal or are they seized?
One caliper will have more friction (internal) than the other. So one will load up first, then send more pressure to the other side.
Put it together, jack it up, step on brakes, have buddy try to spin tires (front;D), if he can one caliper is not workin. Altho, if your off the brakes and one tire decides it don't wanna move, you got caliper prob.s.


GMCworktruck said:

The ebrake won't grab either which tells me that I haven't set them up properly. I'll probably need to pull the line forward abit more.
See first post.
After that, adjust cables.

I'ld start by adjusting the rears, then check out the fronts.
Good luck.
 

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Discussion Starter · #4 ·
Hey Rogue,

Thanks for the reply...

I should of said cylinders not calipers in my post. oops. I'm strictly dealing with the rears.

I've been thinking about this all day and have some new insight. If one side drags more then the other then that drum must be more woren out(?) I think you hit it when you said that I need to back the stars out more. I'll try this tomorrow and see how it goes.

How about the cylinders? One side moves but the other, nada. Tried to move em with pliers but they feel like they're not supposed to move. I even tried to hit em a bit but no movement. The side that does move is the one with the larger shoe. Now this seemed strange but then again I'm new to this so it's prolly right... On the drivers side the larger shoe is facing forward. On the passenger side the larger shoe is facing backwards. And therefore the spring setup is reversed. I took digital pics before I took them apart. Sound about right?

Oh and btw: It has no power or power assist to the brakes. I'd like to retro a booster at some point as well as, power steering!

G
 

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GMCworktruck said:
If one side drags more then the other then that drum must be more woren out(?)
worn out or not shouldn't make that bigg a diff cause the wheel cylinders & star wheels will compensate for that. The more 'worn out' the drums, the bigger the ridge will be along the inside edge of the drum. Unless your shoes run the whole surface.
GMCworktruck said:
How about the cylinders? One side moves but the other, nada. Tried to move em with pliers but they feel like they're not supposed to move. I even tried to hit em a bit but no movement. The side that does move is the one with the larger shoe.
you should be able to twist or move both studs coming out of the wheel cylinder. If it were me I'ld just replace them. Prob. $15/$20, as everything else is 'bran spankin new'. Why keep old/cheap cylinders.
GMCworktruck said:
On the drivers side the larger shoe is facing forward. On the passenger side the larger shoe is facing backwards. And therefore the spring setup is reversed. I took digital pics before I took them apart. Sound about right?
Actualy it sounds about wrong. The larger shoes should be facing the back of the truck. (trailing shoe) Common mystake as someone thinks "bigger shoe on right side, small shoe on left side" then works on the opposing side and puts the bigger shoe on the right hand side and small shoe on left (backwards).
Because the shoe assembly 'floats' at the bottom, as the drum goes around it kinda pulls the 'trailing' shoe into itself(towards the back) as you brake. Unless your reversing. Since the 'trailing' shoe does more work, its usualy longer (surface area) than the leading shoe.
Hope I haven't 'baffled you with bullsh!t' too much.
Pop for some new wheel cylinders, adjust the star wheels, and flip the drivers side shoes around (prob. springs too) and enjoy the new luxury of braking. :D :D
Good luck.
Lemme know if it works for ya.
 

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Discussion Starter · #6 ·
I picked up new cylinders and installed them today. The old ones were definitely seized. Now both longer shoes are facing the back of the truck.

I checked the front brakes as well and they are almost new. Thick pads.

Now after installation (and bleeding) everything seemed like they were working great. This was up on the jacks. I lowered the truck and tried out the ebrake. HEY! I got some now :) Then the real test. Took it out on the road and it's only marginally better then before :(

Back up in the air and adjust the stars out.... more drag... same result.

ebrake on half way and adjusted the stars out til they stopped. My driveway is on a slight incline and the truck on the flatter spots would stop. Ok now I have LOTS of drag. Out on the road... it's better but I STILL cannot lock em up. Is this how manual brakes work??? I'll be driving it for work, which basically means that I'll be in the truck going from address to address all day.

The truck stops alot better then before but still won't make a fast stop. I wonder if this is as good as it will get?

G

PS. I found a 88 S10 with no engine but a brake BOOSTER!! I'm gonna see if they guy will part with it.
 

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Does the peddle feel squishy when U brake?? My guess is that you still have a lil air in the lines if all else is good.
The other thing to check would be the flex lines. One in each front corner and one in the back (generaly). If they are shot they 'usually' kinda balloon a bit at the fitting ends. Sometimes they will have little cracks (like slices) in them.
If this is the case, when you step on the brakes the flex lines will swell (very little), absorbing some of the braking pressure.
Give them a once over, that might be your 'new' problem.
Good luck.
 

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Discussion Starter · #8 ·
I definitely bled out the air... I got the bleeder kit and filled it up 3 time on each side. The peddle is nice and firm.

I'll check the soft lines in the am and see if there are any bulges in them.

I spoke with Budget and the guy said that with manual brakes that's all you get. And I'll need to drive accordingly. I'm gonna knock on my neighbors door tomorrow and see if he'll part with the brake booster. Budget told me to make sure I get the "proportioning valve". What is that and can you describe it? Will the booster just bolt in or is there something I have to hook up or be careful of?

Thanks for your help RogueBronco, I just don't feel safe with the brakes like that, considering how people drive these days. Plus the amount that I drive from day to day.

G

The upside is that I'm saving ALL the labour and by now I'm looking at over $300 bucks! :) PLUS I'm learning how to fix my truck :cool:
 

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Looks like if you swap the booster in, youll also need the master cylinder. Power has bigger stroke and larger bore. The rod on the back of the brake peddal is prob. gunna be different lengths too.
If ya scooped everything between the bake pedal and the brake lines you should be alright. The proportioning valve should be between the master and the wheels, if ya follow the lines out of the master cylinder they should lead ya right to it. block-o-metal, couple lines in / couple lines out. Your probly gunna have to re-route some brake lines, and definately gunna have to do some flaring to swap it in. Not a bad job once ya get the hang of it.:D
Where you at anyways??
And how far over your head are tryin to get??:laugh
You done this type-o-thing before??
Good luck & power to ya:cool:
 

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Discussion Starter · #10 ·
About this :******* deep! lol... I haven't really done anything like this before. I've helped friends work on their vehicles but never got in there to do it. I just couldn't swallow the money shops want to do brakes so when everyone told me it was easy, just a PITA, I decided to go for it. I figure I'm good til I need a micron-meter or specialized tools.

I'm in North Surrey (upper crack-ville, no offense to others that live in Surrey, but I live close to that "house of horrors") cheap rent and a big back yard for my poochies.

If I did scoop it all, which it sounds like I'm gonna have to, would the holes in the fire wall be the same for a S15 and S10? Worse case the donor is +/- a few years. Rerun brake lines... to get a larger diameter?

G
 

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My parts book states that masters from '83 to '90 are the same, so the firewall mounts(holes, ect.) should be identical.
Re run brakelines
not to make them bigger, but to match the lines to the proportioning valve. They might be identical (unbolt one, swap for other), but might need to re route a line or two if they are different. Are ya sure they are different?? I wouldn't be too surprised if the valves are the same with or without power. Thats if your has one to begin with.
 
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