AMC Eagle Den Forum

The Shop => Suspension, Steering, Brakes, Wheels & Tires => Topic started by: kajsdf on June 06, 2011, 10:42:46 PM

Title: brake drum adjustment problem
Post by: kajsdf on June 06, 2011, 10:42:46 PM
finally got around to replacing the shoes on my eagle, and i successfully re-assembled everything....problem is, when i go to put the drums back on, the shoes are out too far to get the drum back on...it appears that the cylinder is still pressurized a bunch -- does anyone have any suggestions? 

thanks for any help
Title: Re: brake drum adjustment problem
Post by: Sunny on June 07, 2011, 01:18:34 AM
You didn't touch the brake pedal with the drum off did you?..
Sometimes they blow the piston and spray brake fluid everywhere..
Sometimes they just extend the piston, to the point that it won't go back to being seated.. So the brake shoes will stay 'pushed out'.
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 07, 2011, 04:06:07 PM
no, i didn't...

the shoes were worn all the way to the frame, would that have anything to do with it?  they were on the car when i got it and i wouldn't be surprised if they were the original shoes (only 87k miles)
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 07, 2011, 04:41:31 PM
The wheel cylinder pistons should be easy to push back in.
Use a C-clamp if required. They may be rusted tight.
If so, they should be taken apart and cleaned.
New ones are a good option too, since they cost about $10 each.
Did you turn back the auto-adjuster at the bottom?
Title: Re: brake drum adjustment problem
Post by: Sunny on June 07, 2011, 08:06:32 PM
If they were that worn. It's probably what Jurjen said.
They probably were pushed out.. and rusted out.
Title: Re: brake drum adjustment problem
Post by: BenM on June 07, 2011, 09:01:11 PM
Open the bleeder when you push them back in, that makes it much easier.
Title: Re: brake drum adjustment problem
Post by: eaglefreek on June 07, 2011, 09:04:56 PM
Most likely the adjuster like Jurjen said. You need turn the star wheel to adjust them in. If the wheel cylinders don't go in, you may have a clog in the lines. If that is the case open a bleeder valve and then try to push in the wheel cylinders. If they go in with the bleeder valve open your clog may be in the rubber line going from the line on the chassis to the lines on the rear end.

Title: Re: brake drum adjustment problem
Post by: kajsdf on June 07, 2011, 10:32:13 PM
thanks for the suggestions, guys...they all seem likely...the pistons were pretty clean, though. 

the bleeder screw is the skinny one, right?  is it a hex key or torx (it's dark out and i can't go look)
Title: Re: brake drum adjustment problem
Post by: 68AMXGOPAC on June 07, 2011, 11:38:37 PM
Did you turn the star adjuster back in all the way?? and make sure your emergency brake isn't on.........only 2 things besides the wheel cylinders I can think of.
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 07, 2011, 11:57:01 PM
e-brake is off and star wheel is in all the way
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 08, 2011, 06:14:32 AM
You will probably have to shock the bleeder nipple free.
I mostly use a 2 pound hamer and punch and hit it sideways twice at a 90 deg angle.
If you can use a hex socket to open the bleeder.
Title: Re: brake drum adjustment problem
Post by: 68AMXGOPAC on June 08, 2011, 07:40:53 AM
Quote from: Jurjen on June 08, 2011, 06:14:32 AM
You will probably have to shock the bleeder nipple free.
I mostly use a 2 pound hamer and punch and hit it sideways twice at a 90 deg angle.
If you can use a hex socket to open the bleeder.

You are kidding right ??
Title: Re: brake drum adjustment problem
Post by: dkoug on June 08, 2011, 11:49:11 AM
While we are on brakes

82 eagle Wagon, brake pedal going down a bid to much to my liking and new 5000 clicks ago..  I know with some other cars by backing up and applying the brakes it will make adjustment to the brakes (thinking rear brakes).

What is the method on these wonderful Eagles.

My 78 Concord brakes are also new with about 2000 clicks, when applied with normal pressure no squeal but with a slight pressure the pedestrians know I'm in the neighborhood-lol

Solution???



thanks

dkoug

Title: Re: brake drum adjustment problem
Post by: Jurjen on June 08, 2011, 12:05:45 PM
Quote from: 68AMXGOPAC on June 08, 2011, 07:40:53 AM
Quote from: Jurjen on June 08, 2011, 06:14:32 AM
You will probably have to shock the bleeder nipple free.
I mostly use a 2 pound hamer and punch and hit it sideways twice at a 90 deg angle.
If you can use a hex socket to open the bleeder.

You are kidding right ??

Nope, I would never make jokes like that.
When I started working on cars, I have broken a few bleeder nipples.
Normally the nipple is rusted tight, so if you hit it twice (near the base as possible) you will shock the thread free.
By the the way this also works on the Philips head screws, you find on many seventies Japanese motorcycles.
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 08, 2011, 12:09:45 PM
.... and on the Allen bolts used on the CV-shafts of the Eagle.
I got them out without using a burner or damaging the hex recess.
Title: Re: brake drum adjustment problem
Post by: 68AMXGOPAC on June 08, 2011, 09:45:38 PM
Well , I really knew you were serious, but they are so prone to breaking, I would fear to hit them. I usually soak them with PB Blater for a couple of days ahead.I also will hit a phillips or a bolt straight on to " shock" it, with the driver or socket in place, it does work well, or even try to give it a jolt in the tightening direction to.Alot of the bikes I work on are from the early 20's to 30's , takes alot of patience to get some fastners out.I have trouble getting sockets/wrenches for the BSF applications. ( British fine thread).
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 09, 2011, 06:20:42 AM
Yes they are prone to breaking. So when you plan ahead, soaking is a good idea.
I didn't say you have to hit them hard, but you need the mass of the hammer to shock them loose. Easy does it, Germans call it "Fingerspitzen Gefuhl" (fingertip sensitivity).
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 09, 2011, 10:26:06 AM
i was able to use a socket wrench on mine. 

managed to get the cylinders pretty much completely compressed but now i have a new problem -- the drums still don't fit. managed to get one on, but that one is worn to just barely outside acceptable specs...and it still rubs on the shoe.

i am now thinking e-brake tension is not allowing the shoes to get as close together as they need to be...thoughts?
Title: Re: brake drum adjustment problem
Post by: 68AMXGOPAC on June 09, 2011, 01:19:16 PM
could be, did you put that ebrake bar that goes between the shoes back on right ??It lays across the top of the axle and is notched, fits in a slot in each shoe.......there should be a blow up picture I would think in the Eaglepedia?? Not sure.
Title: Re: brake drum adjustment problem
Post by: BenM on June 09, 2011, 02:14:00 PM
Quote from: 68AMXGOPAC on June 08, 2011, 09:45:38 PM
Well , I really knew you were serious, but they are so prone to breaking, I would fear to hit them. I usually soak them with PB Blater for a couple of days ahead.I also will hit a phillips or a bolt straight on to " shock" it, with the driver or socket in place, it does work well, or even try to give it a jolt in the tightening direction to.Alot of the bikes I work on are from the early 20's to 30's , takes alot of patience to get some fastners out.I have trouble getting sockets/wrenches for the BSF applications. ( British fine thread).

I've some of those "Witworth" sockets in my box. Occasionally they work for worn bolts, but I've never used them on a British fastener.

Lots of good ideas for freeing the bleeders. You might as well replace them if they're hard to remove, they're cheap. I've pulled them out of cars and seen a little anti-seize on the threads too, but I don't know how it would affect brake fluid and parts.
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 09, 2011, 04:32:24 PM
I found a picture of a typical AMC rear brake lay-out.
You can check wether you have all the parts in the right location.
http://www.marlinautoclub.com/marlin-guy/images/rear/image037.jpg
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 09, 2011, 04:48:52 PM
everything is as it appears in that picture, except for where the e-brake bracket sits on the left side of the picture -- it is not nearly that close and i believe that to be the issue...any ideas how to remove that tension? i have tried the brake release switch in the car
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 09, 2011, 05:34:53 PM
You can undo the e-brake from the balancer near the left rear wheel and work from there
(see if you can slide it in and out).
Last time I did the rear brakes I removed the rear e-brake cables completely and gave them a good lube job.
Title: Re: brake drum adjustment problem
Post by: maximus7001 on June 13, 2011, 06:19:40 PM
I would just replace the cylinders while you got it apart. They are real cheap and can be a serious safety concern.
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 14, 2011, 04:05:03 PM
i think i will probably do that...

jurjen, what did you use to lube the cables?
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 16, 2011, 04:44:51 PM
To get them going again, I used WD40 (you could probably use PB blaster).
Them I lubed them with a thin engine oil (5W40 or whatever you have in store).
Title: Re: brake drum adjustment problem
Post by: kajsdf on June 22, 2011, 02:58:49 PM
finding time to work on this is tough....got too much going on...kinda sad that a job that should be done in an afternoon has taken me over two weeks...

anyway the cables are frozen basically from the T plate where they attach to the pedal-cable to the wheel itself.  using the e pedal in the car i can tension them properly but upon releasing the pedal, the tension releases up front like it should but the cables do not 'spring' back where they should inside the wheel itself.

i replaced the cylinders as well so i know they are not a problem.

any ideas?

jurjen, eggs to you for your help so far...
Title: Re: brake drum adjustment problem
Post by: Jurjen on June 23, 2011, 01:54:56 PM
Thanks for the Eggs. Frozen E-brake cables are a common problem.
When the cables are frozen, it can be difficult to get them going again.
When time is on your side, you can remove them and hang them vertically and spray PB blaster (regularly) from the top. You then have to wait until it comes dripping from the bottom.
This may take a few hours, but may also take two weeks.
New cables are still available from Rockauto and cost about  $20 each.