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Inner Brake Drum Diameter?

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TexasSprite

TexasSprite

Jedi Hopeful
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Anyone know what the spec is supposed to be for inner brake drum diameter? I am still having problems getting the brakes working on my 59 BE. I know the MC and the front calipers are working fine, but something in the geometry of the rear brakes is off. For one, I can rotate the adjuster cam all the way out and only get a minor drag on the hubs, so thought I'd see if new drums are in order, or continue to look for something else. Maybe e-brake. It will lock the drum, but takes almost all of teeth on the pawl to so do. The ebrake adjustment on the rear axle is aready adjusted nearly to the max of its extension.

Any ideas?
 
Are these late style brakes on an early axle housing?

If so, then you will need to turn about .080" from the brake drum edge (if I remember correctly). This is because of the mounting flange for the backing plate is mounted out a little further on the early tube. It may also mean that the hub rubs the dust boot on the brake cylinder.

or... if these are original brakes then I've typed a lot for no reason.
 
I've run into some aftermarket linings that have friction material on them that is too thin. Like trying to adjust worn out brakes! Minimum thickness on new lining is .187".
I cant remember the drum dimensions off the top of my head. I'll see if I have a new one here to check.
Jeff
 
OH... I see he said adjusters all the way out.
 
Like I said on another message board: I need to get a refund on my speed reading course.
 
All Spridget drums are the same, front (if you have'em) or rear. 7". Drums interchange. Yes indeed, there are some shoes, rebuilt mostly, that are too small, either the lining is too thin, and/or the web has been sand blasted enough times that it's gotten shorter. The quick and dirty fix is to weld a blob on the fixed (non-cylinder) end. All it needs is about an 1/8" on each shoe. BTDT

Peter C.
 
The Forum comes through once again.

I'll try Peter C's welding blob idea to change the geometry and see if that fixes the problem.

Thanks!!

PS: The brake setup in my BE has a MC resleeved to 3/4", front disk brakes, original rear drum brakes (with new shoes and cylinders). I had planned to use later model backing plates, etc. but when I went to mount them, it looked like there would be major interference problems, so I went with the original setup. I think the later model backing plates came off of a 1500, but they looked like what people use for the upgrade.
 
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