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Sierra Drum Brake Orientation
gingerprince - 31/3/09 at 06:39 PM

I've got my back-end apart (oo err) whilst I paint my chassis, and I've notice that comparing my rear drums to Haynes, they look the wrong way round.

This is the picture from Haynes, where 'A' is the leading show, so it's clearly the left-hand-side of the car: -

Sierra Brakes from Haynes Manl
Sierra Brakes from Haynes Manl


However, the orientation of the brakes on the left-hand-side of my car looked like this: -

Drum Brake 1
Drum Brake 1


Whereas the right-hand-side looked like this (the same as the Haynes picture): -

Drum Brake 2
Drum Brake 2


So to me it seems like it's the wrong way round. My guess is that I should swap sides, and see if it's possible to re-route the handbrake cable to enter the drum from the front rather than the (current) rear configuration.

But before I do, can someone please confirm whether mine are currently wrong, and whether it actually makes a difference at all? And how do others with MK's have their handbrake cable routed?

I didn't build it by the way, so if it's wrong I'm absolved


Keith Weiland - 31/3/09 at 06:55 PM

Yes, yours are wrong, I just removed mine this week from my donor and they were the way they are in the diagram and the cable enters from the front.


flak monkey - 31/3/09 at 07:10 PM

I put mine on upside down and on the wrong side so the cable enters from the back and the leading shoe is still the right side.

Its a common thing to do, and they work really well. No probs on the brake rollers.

David


Keith Weiland - 31/3/09 at 07:14 PM

If you put them on the wrong side and upside down the cable would enter from the front. Sounds like you just have them upside down


flak monkey - 31/3/09 at 07:18 PM

quote:
Originally posted by Keith Weiland
If you put them on the wrong side and upside down the cable would enter from the front. Sounds like you just have them upside down


Oh yeah only half with it today!


gingerprince - 31/3/09 at 07:59 PM

Cheers both. I'll have a look tomorrow to see what will best suit the handbrake cables.

Incidentally, what impact would it being the wrong way have had? Would it have affected the self-servoing at all, or the self adjuster, or not really much at all?

Thanks, Simon


Keith Weiland - 31/3/09 at 08:10 PM

I shouldn't think it would make much difference if at all on drum brakes which way round they are or if the are upside down. If it were me I would leave it the way it is, I assume it passed SVA that way and works so why mess with it.


Macbeast - 1/4/09 at 07:01 AM

I tried putting them on upside down but the the holes in the backplate are not evenly spaced so it didn't work.

I have them swapped left for right and it all fits but haven't tried them in anger yet.


JAG - 1/4/09 at 07:20 AM

Drumbrakes work much better if they are on the correct side and the right way up. The direction of drum rotation and the lining material position is quite important.

Fitting them as you have them will reduce the effectiveness of the foot brake and increase the effectiveness of the handbrake (only in the forward direction).

If you can cope with these limits, and the slightly difficult handbrake cable routing, then they will work fine the 'wrong' way round.


gingerprince - 1/4/09 at 06:08 PM

Cheers all.

I'm going to try and fit them the right way around. I can't put them upside down, the holes in the upright don't then match the back-plate. I've never been happy with the performance of the rear brakes (MOT I had to press damn hard to pass efficiency) and no matter how far I move my bias aduster (Willwood jobbie) I can't lock the rears (I know I don't want them to, but I'd assume I should be able to adjust them that far!)

I've trial-fitted the cables and it looks like I can approach from the front. Cable route is bendier, but still operates freely throughought the suspensions range of movement.