ShadowTek

I recently changed the rear-left wheel bearing on my '88 22re 4wd pickup; I also changed the seals, wheel cylinder, shoes, and hardware kit. I set the adjuster about half-way and then repeatedly pulled the parking brake to finish the adjustment. Before I let it down off the jack, I spun the wheel and didn't notice any abnormal resistance, but after a few drives I began to smell brakes burning, and noticed that only that one wheel was warm/hot when I stopped. It's obviously dragging a little, but not enough to hold me back as I can still roll easily on a very slight slope when I left off the brake.

Could this be due to only having changed the shoes on the left side? I bled all the lines thoroughly, including from the proportioning valve, so I doubt there's a fluid obstruction.

I've never had any brake-drag issues before.

ev13wt

Have a look at the little bolt / washer setup where the parking brake goes to the rear axle. 1:2
Those love to rust shut. THen you don't have any balancing from side to side.

Also: do the other brake as well.

ShadowTek

I finally got around to pulling the drum off today. I ran the adjuster in some, put the drum back on, pulled on the bellcrank and ebrake until the clicking stopped, and everything seems properly adjusted just like it was after I put it all back together last time. It seems that the adjuster is over-adjusting while driving, but I can't duplicate the over-adjustment just by pulling on the bellcrank or ebrake.

That backplate is a little warped, and there is some uneven wear on the new shoes, but I still don't understand why I can't duplicate the over-adjustment manually or how I can prevent it from happening again.

75w90mantraN

As previously mentioned, other side for equal adjusting/engagement of brakes. Then re-adjust.

ShadowTek

The cable tension and action is correct.

I found the old brake shoes in the garage and they were like new in terms of thickness, so there shouldn't be any difference there.

akwheeler

I have seen problems like this in the past when the parking brake cable was not adjusted properly (too tight). I always loosen the cable then adjust the rear brakes manually through the slot in the backing plate then adjust the cable to get about 7-8 clicks before the handle comes up tight. Seems to work every time

ev13wt

Nope. Just loosen up that nut on the "balancer" part, where one cable splits into to. I bet the problem will disappear.

ShadowTek

I went for a drive and then checked for heat, but it was perfectly cool to the touch. Maybe the issue won't return, but I'm suspecting that it may over-tighten again at some point. If it over-tightens again, I might try tightening up on the bellcrank adjuster as much as I can without causing drag in an attempt to reduce the throw-travel of the self-adjuster. That might not work, but I'm having trouble visualizing what else could solve the problem seeing as though nothing else seems to be out of order.

akwheeler

you are thinking backwards on this, tightening the cables will not reduce the throw on the self adjuster, it will actually make the brakes over adjust. I have see it before and that is why I recommended you loosen the cables, adjust the star wheel, then adjust the cable so that the parking brake grabs well at 7-8 clicks.

75w90mantraN

Have to reiterate on at least checking the other side during brake pedal / parking brake applications. What you saw with old vs new shoes may not be within tolerances. That can illustrate how significant the loss of even minimal wear on shoe thickness on one side can affect distribution of braking surfaces for both sides. Worth checking, knowing you make the final call. Never been recommended to do one set of anything especially on brakes. If working on someone else's, they call that half-a!!

Another perspective...if the side you did ends up wearing unevenly from the neglected side, likely before their full usage you'll end up buying a whole new set of shoes and doing both sides to fix a preventable mistake.

Worst case, its a perfect example of neglect in a motor vehicle accident. Hope thats not the risk you take with the front pads/rotors.

Just cautionary stuff to put out there. I mean even the title should grab attention.

akwheeler

Just incase you (or others) don't know, in order to do a proper drum brake replacement you need to inspect the rear axle seals and slave cylinders for leakage, then measure the rear drum inner diameter and replace drums (in pairs) if they are past spec (stamped on the drum). After removing the drums and hardware clean the backing plates and lube the landings where the shoes contact them (I use the grey lube that comes with front brake pads), if they are deeply grooved at these points you should either replace the backing plates or grind/weld/grind them back to smooth. Then you replace the shoes and install new hardware (unless you want to risk a spring breaking and ruining your new brakes). If your drum is still within spec it is a good idea to resurface them, this gives the new pads a flat surface to work with and gets rid of the lip that makes it hard to remove your drums, buy you need to find a shop with a brake lathe and they still need to remain within specs.
After all of this you should loosen the parking brake, adjust the star wheel until you can just get the drum back on and after applying the brake pedal a couple of times readjust the star wheel through the slot in the backing plate until you JUST start to feel the drum dragging when you turn it by hand. THEN adjust the parking brake to fully apply at 7-8 clicks.
As stated above, brakes should always be done in pairs, otherwise you will end up with a pull to one side under braking, uneven brake wear, or even issues like yours of brakes burning up on one side.
Good luck and let us know if you get it ironed out.

ShadowTek

Thanks for the ideas.
It may be a while before I get a chance to drive/work on it some more. Maybe it'll be warmer weather by then.

snippits

Good post @akwheeler !

I just did the rear brake shoes on my 2wd which is just a little bit different than 4wd. I had no leaks. I still replaced both wheel cylinders with new ones.

I know the OP mentioned the back plate was bent. That plate needs to be straight. Pretty sure the plate can be repaired, or just find a used, or buy a new one.

The nibs on the shoes contact six spots on the backing plate. I wire brushed those spots, and they were smooth. Did not need to do any stoning, or sanding with emery cloth. I used moly paste on the backing plate nib contact surfaces.

I had one side to drag. I adjusted both sides through the backing plate hole. My mistake was adjusting the parking brake cable after the brakes had been adjusted, and then not adjusting the brakes again. Adjusting the brakes again after the parking brake cable had been adjusted to proper pull fixed the drag.

ShadowTek

It must have been the slight warp in the backplate. I replaced that and haven't had any problems since. I guess the lesson to learn is that backplates need to be PERFECTLY straight or it might cause the adjuster to be triggered while driving.

Thanks for the comments!