Newer brake drum locks up when lug nuts tightened - '78 FJ40 (1 Viewer)

[Pighead]

Maybe, take the shoes off and put the drums on and torque down. See if they turn. Rule out everything but the shoes...

 

[SteveH]

That's a pretty good idea - will do, and will report back.

 

[SteveH]

OK. I removed the shoes and reinstalled the offending drum with lug nuts, and there was no drum lockup. I compared the new Bosch-brand shoes to the old shoes (unknown maker), and the friction material is a lot 'longer' on one end, and placed differently on the shoes. Note that the old shoes were not worn out, but one suffered separation of the lining from the backing plate.

I then backed the adjusters way off, and reinstalled the shoes and the drum and lug nuts, and it spins freely. I fear that even the slightest adjustment will cause it to lock up, but we'll see. Anyway - time for photos:

I will reinstall it all, adjust as tight as possible, and report back.

 

[SteveH]

Update - I was fixing a suspension issue and just got it back on the road:

I reinstalled all the parts, adjusted the shoes until they were just grazing the drums, and test drove it. The wheels spun freely even with tight lug nuts, so that problem is solved.

Clearly has more braking power, but pulls slightly to the right when braking, and it feels like it's from the rear, in that the steering wheel doesn't pull in your hands. I suspect that some more driving and bedding-in of the brakes will help, along with minor shoe adjustment. I think it's 'fixed'. I guess I won't take the simplicity of a rear brake job for granted in the future.

 

[cuencanolenny]

Got shoes in the slots on the brake cylinders?
Look and see if the springs are on properly.
The springs go between the shoe and the backing plate.
A picture of the brake installation with drum off might help.

Update - I was fixing a suspension issue and just got it back on the road:

I reinstalled all the parts, adjusted the shoes until they were just grazing the drums, and test drove it. The wheels spun freely even with tight lug nuts, so that problem is solved.

Clearly has more braking power, but pulls slightly to the right when braking, and it feels like it's from the rear, in that the steering wheel doesn't pull in your hands. I suspect that some more driving and bedding-in of the brakes will help, along with minor shoe adjustment. I think it's 'fixed'. I guess I won't take the simplicity of a rear brake job for granted in the future.

Coolerman's article on drum brakes shows that the long/short end of the shoes must be positioned correctly.

 

[BeerM3]

Cheat sheet for correct spring location. I remember it as "outer spring to the back". Your left side looks backwards, but as to what difference that makes, I'd be curious to know too. I found this somewhere and saved it when working on my drums. If you look closely you'll notice it also shows, somewhat exaggerated, which end of the brake pad faces toward the front.

 

[SteveH]

Thanks - I adjusted the brakes last night, but need to take it for a spin. I looked in the FSM, and it showed the springs in the orientation I used. If I can find that illustration, I'll post it here, and we'll see if they match or differ.

 

[Avattack]

SteveH, I had the same problem after my knuckle rebuild, tire rotation, and brake adjustments. My right rear hub locked up and I couldn't get it to turn after I zipped everything up. Frustrating as hell! I ended up backing off the brake shoes in the rear and started over again. Took me awhile and after a lot of patience and beer, I got it to work. Glad you got your 40 back on the road. I love'em but sometimes it's a "LOVE HATE" relationship!

 

[SteveH]

I finally test drove after adjusting the LR brake tighter (so it locks up sooner), and now both rear wheels lock up at the same time on dirt or pavement, and it doesn't pull. Clearly, you need to 'tune' your rear brakes carefully when you adjust them.

Also, I checked the FSM and it matches the diagram in reply #25, as far as which springs go outside or inside of the shoes (and mine are correct, in spite of my photography). 'Outer spring is the one one toward the back of the truck', as you said.