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Re: special sport front brakes

Posted: Mon Jun 24, 2019 8:59 pm
by John-B
davidian wrote: Mon Jun 24, 2019 7:56 pm Hello
I have put several posts on the forum today but they are not appearing. am I doing something wrong?
David
We had a server problem at the end of last week which meant no one could see the forum properly, but we thought that was fixed.
It was fixed for UK people but I learnt today that some members abroad still can't use the forum properly. John Hitchings and I don't have access to the hosting service but Peter B has been informed. Please accept our apologies and try again. I don't know when Peter will get it sorted, so please be patient.

Re: special sport front brakes

Posted: Tue Jun 25, 2019 1:57 pm
by davidian
Hi Chris.
I dont know if this post will appear but when did you buy David beales book? I bought mine in 2007 and has no mention of the front brakes in it . I will be bloomin annoyed if the solution to my problem is in his revised book.
David.

Re: special sport front brakes

Posted: Tue Jun 25, 2019 6:20 pm
by Db n j
David, sorry I posted on this thread but it's diapered,.

There is a girling data sheet, for db18 consort, but it's of limited help.

As I understand it you haven't stripped the front brake yet, but can see that only 1 shoe is moving.

The front system has a single cylinder which pushes a cone forward against 2 wedges moving each shoe (at the top of the drum)
So when you push the brake pedal the 2 shoes are pushed onto the hub.

The bottom of the shoe is basically a pivot. Once adjusted, the only minor movement is to balance the 2 shoes.

I would remove the hub, and get someone to operate the brake to observe the movement.

(Take care not to over extend the movement, ,usually a couple of screwdrivers will help)

If the shoes don't move at the top, remove the shoes and springs, then remove the 2 wedges, clear and lubricate, before refitting and trying again.

Re: special sport front brakes

Posted: Tue Jun 25, 2019 7:48 pm
by davidian
Hi Chris.
I have found the cause of the problem and 99% sure i have solved it ( a brake test on the local garage rolling road will confirm) After going through a long process of eliminating possible causes my conclusion was one of centralizing the shoes, it was apparent that the trailing shoe was not contacting the drum . I got " Err Indoors" to press the brake and could see the shoes move but could not see if the rear shoe actually touched the drum. the expander and adjuster are both operated by a wedge driven between two tappets so both tappets are expanded an equal amount, if say the leading shoe was one sixteenth from the drum and the trailing shoe three sixteenths the adjuster can only advance the tappet one sixteenth and lock up the drum it cannot advance the trailing tappet more in order to push the trailing shoe into contact. However it was at this point i stumbled across the piece on the Bendix brakes and after reading it a couple of times the penny dropped .in order to adjust these brakes you first have to loosen the screws holding the adjuster to the backplate (its a loose fit in its hole ) then lock up the drums with the square adjuster( this centres the shoes )and while the drum is still locked re tighten the fixing screws, then click back until drum spins. My thanks to all who contributed to this post.
Regards David

Re: special sport front brakes

Posted: Thu Jun 27, 2019 2:28 pm
by davidian
Hi all.
My posts thanking you for your input plus a few others have not appeared . I took the car for a spin down a quiet local road and did some gentle braking to test the cars reaction and as nothing untoward happened gradually increased the braking and speed and made several emergency stops , the car behaved perfectly ,its a different car. I was considering Stan's suggestion to fit Conquest brakes as a last resort ( perfectly feasible ) not necessary now. Just as a post script , when I had the expander dismantled I noticed the wedge had, apart from the normal rollers, a small " pad" which slid from side to side in the wedge ,I am not sure, but I think this gives a bit of differential movement to the expanding tappets