Brakes Constant brake issues on 93 LX

Hi all, I'm in big need of help with the brakes on my fox. It was originally a 4 cylinder but now has nearly all V8 fox parts. I've rebuilt or replaced nearly every part of the brakes besides the mc (stock 4cyl one I believe) and the parking brake cables (the kind with the 4 tabs that lock into the backing plate and cable from the handbrake). My issues is with the rear brakes. I put all new hardware, shoes, and drums on the back, all the brakes were bled to procedure, and the pedal felt great at first. However the rear brakes were dragging from the first time I tested it (last thing I did before driving it after V8 swap), especially the right rear. I turned the starwheel way back until I could move the drums almost freely, and pulled the parking brake, but whenever I do that they tighten up again and start to drag. I put it back together and the pedal started to get very mushy and travel further than before, so I took it back apart and can't find any leaks. The brake would still drag, and yet the parking brake doesnt do anything. I'm lost in where to go, I haven't messed with drums much and I'm not sure if I screwed something up as they don't seem to settle right, or if there is something messed up with the car. Worried it's multiple issues at once. Any thoughts?
 
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Are you sure you have the correct return springs, and that they are properly installed?

And a very little bit of wheel bearing grease where the shoes contact the backing plate helps the shoes move easily and smoothly.
 
Come to think of it, I actually never checked the part number on the kit, I just compared it and it seemed right. Were the 4 cylinder/7.5 rear drum brakes different? That is what the car was originally and it could be for those. And I made sure to put grease on the contact pads
 
Come to think of it, I actually never checked the part number on the kit, I just compared it and it seemed right. Were the 4 cylinder/7.5 rear drum brakes different? That is what the car was originally and it could be for those. And I made sure to put grease on the contact pads
RockAuto shows the return springs (and the whole drum brake hardware kits) to be the same for a '93 4 cylinder and V8.
 
The only soft line on the rear drums is the one from the body hard line to the soft line that has a brass distribution block that mounts to the axle on the passenger side. That could be the issue but if the rear brakes bled then I doubt it is collapsing. It could be expanding when the brakes are applied which would give a mushy pedal but I don't think it would shrink back down, collapse and hold pressure to cause them to drag. Regardless I would have changed all three (rear and two front caliper lines) as they will over time swell shut. My dad's 69 Mustang had this issue and caused the front drum brakes to be impossible to dial in.

Did you change the rear wheel cylinders? These are what the brake lines attach to at the backing plate. They could cause an issue but if they were working fine before is kind of unlikely. I am more along the lines of you did not assemble the brakes correctly as 85GTStangGuy alluded to above. Here is a picture of what the driver side should look like:

1676863058567-jpeg.jpg


Here is what the passenger side should look like:

c-brake-conversion-installation-sve-5-lug-kit_1848.jpg



Notice that the larger shoe (secondary) is on the back and the smaller shoe (primary) is on the front.
 
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Also, the shoe return springs are not the same for the primary vs the secondary shoes. Make sure you have them in their correct locations. I believe the primary shoe return spring is green and the secondary shoe return spring is white...... at least with the Motorcraft kit that's the case.
 
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The rear soft line is new, the two front soft lines are not. I replaced all the hard lines,the wheel cylinders, shoes, drums. I made sure to put primary/secondary shoes where they belong. I have all the springs oriented like that, however my shoes dont seem to sit right on the seat above the wheel cylinder still
Also, the shoe return springs are not the same for the primary vs the secondary shoes. Make sure you have them in their correct locations. I believe the primary shoe return spring is green and the secondary shoe return spring is white...... at least with the Motorcraft kit that's the case.
 
......, however my shoes dont seem to sit right on the seat above the wheel cylinder still

Don't know exactly what the problem is, but that's an indicator that something isn't put together correct, or that something shifted upon assembly. Between the parking brake link at the top and the adjuster at the bottom, it's easy for a component to shift unknowingly when putting everything together. No fun, but an option is to take it all apart and reassemble it. Sometimes that'll fix a problem even though it'll seem like nothing different was done putting it back together.

Also, just thought of something else..... are your backing plates in good shape? No warpage or bendage?
 
You have not out right said it but is the rear end an 8.8 and out of a Fox Mustang? If so are you sure the shoes are for an 8.8? Also, pay attention to the stumpy cross shaped shoe retaining washer such that the short side goes up. You can see what I mean in the two pictures I posed above and this is the part I am talking about:

hw2261_1.2226.jpg
 
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Don't know exactly what the problem is, but that's an indicator that something isn't put together correct, or that something shifted upon assembly. Between the parking brake link at the top and the adjuster at the bottom, it's easy for a component to shift unknowingly when putting everything together. No fun, but an option is to take it all apart and reassemble it. Sometimes that'll fix a problem even though it'll seem like nothing different was done putting it back together.

Also, just thought of something else..... are your backing plates in good shape? No warpage or bendage?
I've been thinking about going that route just to make sure everything is right. Wondering if I should try and put the old springs back on one side and see if it looks any different. I couldn't see anything wrong with the back plates when I had it all apart
 
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You have not out right said it but is the rear end an 8.8 and out of a Fox Mustang? If so are you sure the shoes are for an 8.8? Also, pay attention to the stumpy cross shaped shoe retaining washer such that the short side goes up. You can see what I mean in the two pictures I posed above and this is the part I am talking about
Yes, it's a fox 8.8 with drums, out of an 88/89 I think. Those retainers are sitting like how they are in the picture