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[Marks DTM Calib]

Oooook, I think I see where I'm misunderstanding.

So. With new shoes on and adjuster backed right off so you can easily slip the drum on, you then pump the pedal which actuates the auto adjuster and AUTOMATICALLY sets the shoes in the correct place?

So when I did the shoes on my ma's Ford I could have simply jumped in with the adjuster in any loose position and jammed the foot brake a bunch of times and then took up the handbrake cable slack with the nut adjuster?

If that's the case. . . Why did the head mechanic not do this on a recent van we had in? And this guy knows his onions.? Is it possible he thought the auto adjusters don't work? I vaguely remember hearing him say summat like that. . .?

The clue is in his title lol....he does not understand and probably could not explain how they work 

But yes, when you do the job properly, the auto adjuster will take the slack up correctly....and this is important or the dam things will need manually setting regularly as the shoes wear and if they are not working its a poor quality job........

At the factory they wont be manually setting them

Ask him about the handbrake cable and how it must be when released......see if he has any understanding.

[Marks DTM Calib]

So, a picture paints a thousand words



So the above is a Corsa handbrake mechanism and is now pretty common on many marks but, is good for demonstrating how the auto adjuster works.

So when you apply the handbrake, the large lever on the right shoe is pulled and pushes the shoe towards the drum, the top link/adjuster then simultaneously pushes the left shoe onto the drum.

To auto adjust, you need to look at the adjusting pawl on the left, this can be seen as the bent bit of metal with its end resting on the left end of the link bar/adjuster.

When you press the foot brake, both shoes move outwards, this adjusting pawl moves with them and its end moves slightly up and above the link bar/adjuster. As the brake is released, this adjusting pawl travels down again and rotates the toothed wheel at the end of the adjuster which, over a number of presses, lengthens the link bar/adjuster and takes up the slack.

Lets consider now what happens when the hand brake cable is to tight.

The actuator lever on the right is always under tension and the consequently, the adjusting pawl sits higher than it should at rest, as a result, the toothed wheel can not be rotated.....

[Webby the Bear]

Ok, thanks Mark. Apologies I missed your previous explanation of the mechanism and the correct set up 

So considering what you've said and how we did the job on the van I mentioned. . . . The handbrake cable adjuster wasn't undone; the handbrake merely released. The drums then pulled off, new shoes fitted, and then the drum refitted and shoes adjusted manually until they 'felt' right.

Taking in to consideration the operation of the auto adjuster that you kindly explained. . . The adjustment will never be correct because we didn't leave that slight amount of slack by not slackening it in the first place. . . Although in theory the shoes under normal braking (not handbrake) will get corrected by the pumping of the foot brake. . . But obviously we've wasted a bunch of time on unnecessarily manually adjusting?

I hope tha makes sense. But either way I now totally understand all you've written so thanks for that 

[Webby the Bear]

And of course the auto adjuster won't work because the cable is too taught thus not allowing the auto adjuster to do its job.

Got ya 

[Marks DTM Calib]

And of course the auto adjuster won't work because the cable is too taught thus not allowing the auto adjuster to do its job.

Got ya 

That's the fundamental bit 

So what has been done is a half job, the van will go out and in twelve months time return due to the handbrake not working well (the shoes will wear and the auto adjuster cant compensate......seen this MANY times on Transvestite Vans

The drums will normally just pop off (or may require some persuasion if there is a significant wear lip).

[Webby the Bear]

Cheers Mark.