Help with rear brake problem

[Squirralien]

I have assembled the rear brakes on the FB, its a HR diff and its all gone together quite well BUT,,
I found the drum was hard to get off on one side and when I got it off one of the clips fell out that hold the shoe back,
I then found that the plate/bracket (B in the picture) that rests on to the teeth of the adjuster on the bottom was sitting about 5mm off of the teeth,
then I moved the shoes a little and found it would sit on the teeth of the adjuster but then the Bar at the top (A in the picture) with the hook on each end would be
that loose that it would fall off if you touched it, this should be really tight and a pain to put on not falling off from touching it,,
Any ideas or suggestions would be appreciated
Thanks

[Squirralien]

Well I went and spoke to the Brake specialists and they have no idea, need to see it,
I'm not sure if that might not just be an auto response,
Well I think I will pull it all apart at some stage soon and put it all back together again
and see if that makes any difference some how,,
Also wondering if It's possible I got the shoes back to front or something similar.
Well If I do find the reason I will post it up here just on the off chance someone else finds the
same issue with their brakes.

[Finny]

I've got one Tim.
HR workshop manual - brakes. With diagrams.











Hope that helps find the issue, Mr SquirrelAlien ???.

[Squirralien]

I can't believe it,, I think the first picture might just tell the story,, I wonder if the shoes are mixed up, I don't think the leading edges are biased like the diagram,,,
Well I will have to pull both sides apart and have a shoe shuffle,, thank to you both and Ill let you know how it goes,, fingers crossed thats the answer,,,,

[Trev]

Have the cylinders got any push rods in the ends?
I can't see any in that pic, I'm probably wrong .

[Squirralien]

Yes Trev they are in there, Unlike the Torana I am also doing this type don't have the small rods that come out they just have the flat plunger that comes out against the shoe

[Craig Allardyce]

Have you had your shoes radius ground to match the drum? This needs to be done to ensure correct shoe fit in the drum. From what I see your adjuster is backed all the way off. When its backed all the way off you'll find the adjusting lever link rod will be slightly loose. As the brakes are adjusted up the shoe will move out and take up the slack. If the shoes are too fat right from the start then you'll have this problem. Also ensure you have the small locating spigoted washer that locates the lever to the brake shoe in place.
Your shoes are also the wrong way around for the direction of rotation of the drum (twin leading duo servo with major braking force in the forward direction which means the forward lining should be down low on the front shoe and the rear lining up high on the rear shoe. This gives better self energising of both shoes in the forward direction i.e. the shoe will pull itself into the drum better in the forward direction of rotation).

[Squirralien]

Thanks for that Craig,, I have never heard of getting the shoes shaved to suit the drums,, who does this,, would most brake places do that,,,,
I have never heard of anyone doing that, is this a national secret to getting them to work right haha,, I'll look into it thanks Craig

[Craig Allardyce]

Yes it is standard practice in the trade but as usual with all things old, and the advent of discs brakes, things do fall away.
Its no secret, they should do it if your having your brakes relined.

You can visually check to see if they need radius grinding by checking the shoe's against the drum when the shoe's are removed. The shoe lining should have full contact along its complete length. Usually if the shoes have been relined you may find that the contact will be either at the ends of the shoe or in the centre (less often in the centre).
I would say most don't bother with grinding the shoe and let the shoe wear in but as you see you may come across these sorts of problems till the shoe beds in. The constant readjusting of brakes till they do is also an annoyance.

Grinding the shoe will help with your drum/s being tight to remove even though your adjuster is back all the way off. After that the adjuster should take up any introduced shoe to drum clearance after grinding. This would then reposition the shoe and link lever further outwards which should take up any slack in the link rod.
Also check Finny's post above as you'll see there were different length link rods. Yours look to be red so your middle of the range so you might be able to chase up shorter ones.

[Squirralien]

ok Thanks Craig, I will check that, I am going to pull both sides off and shuffle the shoes around to get the bias of the linings as it has in the diagrams above,
I am sure this is my problem, I think I have mixed up and put a left and right side together on each side. but I will definitely check that shoe fitment on the drum.
Thanks again to all the comments, It is great when someone can start to see the light through the forum, its what makes the forum as good as it is.
Thanks again and Ill post up the results most likely after the weekend. maybe a few pictures as well.

[Squirralien]

Well I just had another look at my brakes and the shoe on the front side of the brake assembly is biased toward the top centre so it would appear that the shoes are on in the correct way ??? well I will continue with my plan to pull them all apart over the weekend and reassemble them and hope for the best,, and I will also check the shoe linings against the drums
in the picture at the top of this thread you can actually see that the lining is biased toward the top centre mark,, well fingers crossed for the weekend.

[Craig Allardyce]

Well I just had another look at my brakes and the shoe on the front side of the brake assembly is biased toward the top centre so it would appear that the shoes are on in the correct way ??? well I will continue with my plan to pull them all apart over the weekend and reassemble them and hope for the best,, and I will also check the shoe linings against the drums
in the picture at the top of this thread you can actually see that the lining is biased toward the top centre mark,, well fingers crossed for the weekend.

Steven, if anything the front shoe should be biased towards the bottom if it is fitted correctly. It's difficult to explain but if you imagine the shoe as a lever (bottom is the fulcrum) and the wheel cylinder is forcing out the lever at the top of the shoe. If all the lining was on the top closest to the wheel cylinder then you loose any mechanical advantage over the length of the shoe. Biasing the lining towards the bottom of the shoe gives a slight mechanical advantage due to the point of contact in the drum. Also having the lining biased this way for forward rotation you get the self energising principle whereby the direction of rotation of the drum tends to pull the lining down and into the drum face.
Hope this helps.

[Squirralien]

ok so sounds like my bias is back to front,, Ill reverse them over the weekend, thanks Craig,,,

[Squirralien]

Well,,,,,,, I have removed all the rear brakes and replaced them with the bias reversed and also checked the shoes to the drums and they look perfect,, but no change in the original problem,,,

I then decided to just sit there and fiddle with it like a little kid and in doing that discovered that the bar with the hook on each end A in my original picture was not holding the correct position being slightly too long, So I took them both off and increased the bends and tightened the hooks on each end and boooom there was connection from the adjuster to the locking plate.
I then noticed that the adjuster on the passenger side was also a drivers side adjuster so it was winding backward and not working as it should, I just happened to have kept the rusty ones and found the right one and wire wheeled it and polished it, greased the thread and put it in and all good, Job done,,
thank you all for your input/suggestions and hopefully someone might see this in the future and be able to sort the issue out. maybe the same problem or solution maybe a suggested solution but either way I hope it helps someone apart from just myself...
Thanks again Craig, Trev, Finny and SunnyTim

[Trev]

Thanks for sharing your problem and solution .