Another Brake (drum) problem..

Ok, I'm gonna ask here for my brake-problem witch keeping me busy the last 8 months:

Car: Chrysler Newport 1971, disc/drum (11 x 2,5 inch)
Problem started with replacing the rear brakeshoes. Brakes kept dragging, however I adjusted them. First only the passengerside, later also the drivers side.
Trying to solve the problem I did:
- new mastercylinder (same as the old one)
- new wheelcylinders
- new rearbrake hose
- new brake hardware
- new brake fluid
As far as I can think of and see: no hydraulic issue. Shoes retract full back to anchorpin after using brakepedal. Car stops very good but rear drums get to hot to touch after a few miles.

So, what did I check next?
- backingplate
- wheelbearings
Seems all OK.

Last thing I did:
- had the linings on the shoes replaced, Linings are a bit thicker now and primary and secundary shoe have the same thickness
- drums are turned
Still dragging...@#$%^&*

What I've noticed is this: both wheels of the ground, brakes adjusted, to a very very slight drag, but when I put the wheels on and tighten the lugs: much drag !! Losen the lugs just a bit: drag is almost gone !! What ??? This is also when I put the lugs just on the drums(without the wheels on)
To make it more complicated: when I set the parkingbrake a few times, drag is gone again. But then I hit the brakepedal a few times and the drums are stuck again.
Also when brakes are free and start turning the wheel by hand, forward and backwards, after 10 to 20 turns, dragging is coming back !! without touching the brakes at all..
I don't know what to do anymore, checked and double checked everything what I could think of..

Ofcourse I've been searching the w.w.w. about this and it seeems that I'm not the only one with this issue..

For those who are interested I also put this on FCBO but unfortunally no solution yet...

http://www.forcbodiesonly.com/mopar-forum/threads/rear-brake-is-driving-me-nuts.25496/

Maybe there's someone here who has the "egg of Columbus"

Luigi

When the rear brakes are stuck, loosen the front line nut on the MC until a little fluid runs out...if this releases the drum(s), there is residual pressure remaining in the circuit when the pedal is released. Could be the MC pushrod is out of adjustment.

Thanks, but also checked that, pushrod is OK..

You turned the drums, did you also arc grind the new shoes?

Have you driven the car using the brakes a number of times. Then pulled the drums to check to see if wear pattern on shoes is fairly consistent across the shoe surfaces.

I did like John's initial response.

Check to see that the shoes aren't to wide. Dragging when you tighten the lugs is a sign of the drum rubbing against the side edge of the shoe.

As far as the tightening of drag with the lugs on I had the same issue with my 68 gmc, took the die grinder with pad to the outer edge of shoes and just smoothed the edge of lining a bit and issue went away seems when they turned the drums a small taper was left near the were the face and shoe run meet( or the azone shoes were a little off) fixed that issue for me previously I had always smoothed the leading and trailing edge on my brake shoes a bit,,, use to come that way but not anymore..

Had the same problem with my 68 Charger, the shop didn't turn the drum all the way to the corner of the drum, causing it to drag when it was tight.
Be sure you didn't swap the self adjuster mechanism and they are tightening while driving forward instead of reverse.

Problem lays on the drum contact..by tightening the lugs..the drum is contacting either the shoes or the backing plates..is it the right drums or backing plates..or even the right shoes..try using a different brand..

what they said, you wouldn't still have your old shoes would you?

I got new shoes from Rock Auto: https://www.rockauto.com/en/moreinfo.php?pk=297366&cc=1066317&jsn=308

Because the shoes kept dragging I took them ( shoes ánd drums) to a machineshop to have a look. They adviced me to remove the linings and replace them with a little thicker and softer ones. They also turned the drums to match the shoes (with new linings on them)

About tightening the lugs: sometimes I can tight them up and the drum turns free, other times the drum turns free for a while but then starts dragging after some turns on the wheel. When I losen the lugs at that time, drum spins free again. I edged the shoes on top, bottom ánd the sides.
So, the shoes touching the innerside of the drum ?? I don't think that but??

Afterall: I cán get the shoes adjusted so the drums spin free, also with the lugs tight but after al while drag comes back even without touching the brakes !

Could it be possible that the linings are to thick now? I must say that I have to turn the adjusters at the bottom allmost fully in..

How about posting a picture of the brakes you have installed. Maybe we can see something you don't. A second set of eyes never hurts.

It the old days brake shoes were ground to fit the drum called arcing. Sounds to me it`s time for new drums.

There should be a mark..a dragging mark somewhere that shows its rubbing..either at the face of the linings or the edge of the lining shoes..either the rear towards the backing plate or the front rubbing the drum.

Ok, here some pics:

First, old (in fact new) shoes, adjusters not installed yet:

[img]https://www.dropbox.com/s/3kr5bny8zi0e6fh/Old%20shoes%201.JPG?dl=0[/img]

Second, same shoes with new linings:

[img]https://www.dropbox.com/s/lcc5cxt4mydhraa/New%20shoes%204.JPG?dl=0[/img]

Last, should I file of more?

[img]https://www.dropbox.com/s/p04g64b4o0b0lla/New%20shoes%205.JPG?dl=0[/img]

Luigi

From the pics it looks like the metal part of the shoe may be hitting the inside of the drum? Also IMO, I would replace the return springs or at least close them up some and close up the clip on the e brake lever.

Sure looks like scrape marks on the outside edge of the metal part of the shoes. I'd have stayed with the original new shoes rather than the reline.

Oh yeah..the markings on the metal shoes show the rubbing marks..those are the wrong shoes too wide ..try another brand

It also could be the drums if you bought them new also..something is too wide (shoes)or not wide enough (drums)

Update: the markings on the metal side of the shoes, were made by the machineshop. They had to make the linings smaller to fit on the shoes..

[q uote=Luigi]Update: the markings on the metal side of the shoes, were made by the machineshop. They had to make the linings smaller to fit on the shoes..


[/quote ] What the Frick, make the linings narrower to fit the drums No Good I'll bet your linings are either 11.0 inch by 2.5 inch wide or 11.0 by 3.0 inch wide with the same size drums, correct? There are several different versions of those size linings and shoes for the different years of the larger diameter 11.0 inch brakes
I know your across the pond which makes it a lot more difficult to get the correct parts for our old cars made here in America, it ain't like you have 14 different local part stores to go to pick parts from like here I would want you to get the correct parts now instead of gerry rigging those parts like they are now

Just ran into similar issue with brake shoes on a Buick The shoes I bought said made in USA didn't" know USA had a state called China? Regardless your shoes are the wrong ones from what I can see Cab above is correct

could it be for whatever reason that the back of the drums are rubbing the backing plate when the lugs are tightened,take all the shoes and hardware off and install the drums anfd tighten them,see if you get some rubbing

Maybe I'm not clear about the shoes.

The original shoes were worn so I bought new ones. When they were dilivered I compared them very very closely with the new ones: put them on top of eachother, holes and everything perfectly lined up, width of the linings, lenght etc, they were exáctly the same size..11x2.5 inch.

So, put the new shoes on and then the problem of dragging started. Adjusted them many times but every time after a couple of miles the drums got hot, very hot. First only RR but later also LR.

Thén I started to replace everything as I discribed in my first post.
That didn't solve the problem so then I decided to take them to a machineshop.

The linings were glazed at some points and that was the reason to put new linings on and turn the drums.
They showed my the new liningmaterial and that were pieces of approx 20 x 4 inches. Thats why they had them made to fit to the shoes and had to file off the sides after riviting them on. So, markings on the side of the shoes explained.

As said earlier, drums can be installed spinning free, also with the lugs tight so absolutely no drag or rubbing at all but....
after several turns, with or without powered by the engine, dragging starts....

I've compared my pics, old and new, and see that the new linings are longer than the old ones, special the primary. Secundairy also, were the scuff marks are..Could that be the reason ??

It's 95 F overhere now, so the brakes have to wait now..

Back in the day when Service station here in the U.S. installed brake lining almost every garage and gas station had a brake grinding machine to taper the leading and trailing edges of the new brake shoes so they would break in properly and no tmake the centers not touch until the edges where beveled.Thye called that "Arcing" the shoes I'm wondering if the front and trailing edges are growing more then the centers when appleid making them bow up (grow) until they start rubbing, which makes them heat up and grow more
Let us know what you find to fix it, maybe run them looser for a while until they seat properly

Update:
Temperature went down here so the last days been working on the brakes again.
Rear end up. Brakes adjusted with very little drag. Put wheels on and lugs tightend. Both wheels turn free in the air BUT !! left wheel starts dragging after 20 to 30 turns backwards...turning forward again runs free.
So I thought: mostly driving forward so out for a testdrive.
Result after 10 miles with absolutely no hard braking: hot drums and wheels! (190 F). Jacked the car up and wheels turned heavy. Losened the wheel lugs a bit and wheels turned free agian ??
I'm totally stunned and don't know what to do anymore.

Shoes are arced and leading and trailing edges are tapered...

& this is with you hand turning the wheel backwards/no pedal input correct? that makes me think something is fubared with the assy on the backing plate: loose holddown springs/brake nails wrong ones (too long) sumpin ain't kosher cuz it (something) is too loose or too big or too small or installed wrong. we'll get it! (might take us awhile). when you turn backwards it is shifting something that should be secure.

The only thing I'm seeing is the upper spring hooks have been 'bent' open a bit. Maybe they lost some tension because of this and they're not able to keep the brake shoes together all the time. Just a guess and doesn't explain the tightening of the wheel nuts issue.

Also the lower green spring is in a different hole than before (left, in the pictures). I *think* to recall it should be mounted more horizontally across, to the same hole in the other brake shoe, as to provide more tension.

Wheels turned by hand and no pedal input at all..I also think that the shoes are moving or something like that. Hardware is all new and before installing compared with the old stuff, and all is the same.
Backingplate is clean and shoes move free...
Bottom spring allready placed more horizontal to create more tension.
Left the top springs open for a while to make it more easy to remove them everytime... I think I disambled the shoes more then 10 times to check everything. With the drums off and a helper pushing brakepedal I see the shoes work fine, out and retracted by the springs..

Are the primary and secondary shoes installed in the proper place?
Primary shoe is the one that goes on the front - it has the lesser amount of lining material...pictures are poor.

I had the same problem on another person's work, 69 RR 11" rear drums.

Be sure the e brake is not a contributing factor

Return spring are showing fatigue-be sure to replace them

I had similar problem on my '89 Dip Police car 11" brakes. Brand new parts, including Raybestos finned drums. It took me forever to figure out it was only when I tightened the lugs down that the drag started. I'd adjust them, put wheels back on, go for ride to get pedal feel, and as soon as I let of gas it roll to quick stop. I know you said you can spin it freely two or three times with lugs tightened; it's been a couple of years since I did the brake job, and I don't remember if mine was the same. I found a set of NOS drums on feebay (cost me 4x as much as the Raybestos off rockauto, but well worth it. Problem solved and I'll get 100k miles out of those drums (maybe more).

Sick of the aftermarket crap!

I agree on it probably being the drums. To me it is either the shoes or the drums.

maybe a silly question,
Is there any chance the adjusters are installed on the wrong sides ??
There is a L and R adjuster and while they appear the same the threads are reversed.

Only other suggestion I can think of is to disconnect the adjusters and or lock them and see if the issue goes away.

re reading your posts made me think of a few other things.

Something is causing the adjustment clearances to change.

1. possible bad axle bearings
2. Axles bent causing the drums to wobble
3. Axle flanges not flat / or true

One could try mounting the drums using either spacers, or stacked washers with lug nuts leaving the wheels off and repeating you testing with the rear end supported on jack stands.

Are the primary and secondary shoes installed in the proper place?
Primary shoe is the one that goes on the front - it has the lesser amount of lining material...pictures are unbelievably poor poor but it looks like you have two of the same shoe on each axle.

Until you verify this all other ideas from the masses are just a guess and dart board troubleshooting. Brake drum systems have been around way too long, this is a simple fix.

I see that no one comprehends that I just worked on a car with some one else's brake work that had the exact same problem...
OK then figure it out for yourselves.

Adjusters are on the correct side. Disconnected them already but no difference..


Shoes are placed correct. I agree that the new linings are longer than original, specially at the bottom.
I've replaced brakeshoes many times in the past and never had this problem before...

My first thought when reading initial post, was to release bleeder valve, or better yet 'crack' hydraulic line at wheels when they are locked. However John K. Had posted to 'crack' line at MC. I could live with that so canned that thought.

However after all you have gone thru and all the thoughts from members thrown out in this saga, what have you got to lose to give this a try.

Another thing that I would try is to take a very thin wheel spacer(say 1/8th), pull drum, place on axle, replace drum, wheel, torque down, do your testing. Does this resolve problem. If so, gives an excellent clue as to where problem lies.

I have seen the wheels pushing up against drum balance weights and deforming the drum. But you can usually see that because the wheel will wobble a little.

Finally solved the problem....
Being só sick of all this at trying to adjust the shoes with no result I ordered a new pair of shoes. This time I ordered Wagner brakeshoes. The first ones were from Raybestos.
When they came in, I compared them with the Raybestos shoes. At first sight the were exactly the same but.....when I measured them it seems that the Raybestos were 0.5 MM !! wider than the Wagner.
Anyway, put the shoes on, adjusted them, took a test drive and...No heating up at al. Brakes work perfect now.

As some members here suggested already: shoes were not good altough they lóóked OK

Thank you all for your input in this..

the offenders were a C hair wider than the correct ones. that was too easy!