Author Topic: Mk Front brake plate  (Read 2500 times)

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Offline dragonmk5

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Mk Front brake plate
« on: 04 Dec 2012 at 13:10 »
On my Mk 4, being unhappy about the amount of movement of the front brake anchor plate on application of the brake, I examined the complete assembly.  Probably in keeping with most other Marks, I found the the hole in the anchor plate to be badly worn,but luckily, not "ovalised" to any great degree so I didn't rebore it but made a new shell bearing to suit.  The end result is that the new assembly is quite a good fit - not too tight to cause binding between the two surfaces, but snug enough to prevent excessive movement.  It's a lot better than my original set-up, but the anchor plate still moves on brake application more than I would like. One area I could modify is the amount which the shell brg protrudes through the anchor plate, currently about 0.010".  I am also regretting blindly copying the inner bore of the shell brg, which is in clearance over wheel bearing housing.   Maybe I should have made it a tighter fit,  albeit with running clearance?

Offline eddie

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Re: Mk Front brake plate
« Reply #1 on: 04 Dec 2012 at 17:16 »
My advice would be to leave the inner diameter of the shell bearing as it is, but open out the hole for the wheel spindle by about 25 thou. Then, when you are ready to tighten the wheel spindle, get someone to hold the brake on - this will centralise the brake plate to the drum. I have found this makes a much improved brake. Reducing the clearance between the shell bearing and the hub could have disastrous consequences if the hub should 'pick up' in the shell bearing - it could suddenly prevent the wheel from turning without giving any warning.
    Eddie.

Offline dragonmk5

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Re: Mk Front brake plate
« Reply #2 on: 04 Dec 2012 at 17:47 »
Thanks Eddie - will take your advice re the wheel spindle hole and assembly method.  I agree with your diagnosis regarding the clearance between the shell bearing and the hub.  The new shell bearing has the same inner diameter as the original component as I saw no need to make any alterations in that area. The comment I made about regretting my failure to consider all aspects of the design only occurred to me while I was typing the post, being disappointed that I had not achieved my aim!! Most grateful for your valued input.
George

 

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