Drum brakes

[Bren]

Having to do the rear brakes on the SD1 because of a leaking wheel cylinder,and having not done drum brakes for ages, I am amazed at what a pants design they truly are. Despite having the Haynes BOL and the rover factory manual, there is'nt really a good description of how to set up the adjusters - most people fit new shoes then get an epic fail at MOT time because they are'nt correctly set up.

 

I have managed to down load a PDF from the internet which explains how to do it - I will venture back into the garage when it warms up a bit and hopefully sort them out. If I cant I shall be donning a stout pair of shoes to hopefully slow the beast down.

[FredTransit]

if you think rears are bad, try drums all round. The first mod we did to our first Mk1 was fitting a Mk2 front axle. Years later had to do the same thing to our Mk1 luton cos of a serial imbalance on the front. Just couldnt get em to balance yet they stopped fine.

[DSdriver]

Our Pug 206 has drums on the rear. It doesn't get used much and when MrsDS decided to take it shopping this week it chose to shed a lining from a shoe. I presume they don't use rivets nowadays? Or asbestos linings. ahh those were the good old days.

[Albert Ross]

You lot are all amateurs! I run un-servoed 11" drums all round, on a vehicle that can weigh just shy of 3 tons. It stops squarely and straight, no pulsing from the pedal, minimal squealing, and moderate pedal effort. All this from a vehicle built 42 years ago, with a braking system designed in 1955. It has manual adjustment, none of the new fangled "automatic" rubbish. I use it daily.

[bub2006]

My motor runs brakes all round. Easy to balance and manually adjust. Stops good too. Mind you it weighs less than 500 kg.

[Morgan84]

Drum brakes on a Mini are quite easy,and the old fashioned method works for me.

 

Clean and lubricate everything first,then put the drum back on,and press the brake pedal to centralise te shoes.

 

Turn the adjuster until you feel resistance,and can't turn it ( gentle pinch ) . The drum now will not turn

 

With one hand on the drum,and the other on the adjuster spanner,back off the adjuster again until the drum then begins to rotate freely again

 

Result should be a good pedal,and good efficiency

[Andrew353w]

/\ /\ /\ as regards servicing drum brakes. I've done loads of them, on old Minis, old Dafs & various bits of chod from behind the iron curtain! Yes, drums need to be adjusted more than discs (which don't need any adjustment until the pads wear out!) but that's a good thing in some ways, as it makes you look at the brakes on a regular basis and spot any problems before they get too bad.

 

All I would add to the excellent advice & comments above is to remember to clean out the drum before re-assembly, as the build up of brake dust can make them squeal. Give the flexi hoses the once over for bulges & splits, too.

[nigel bickle]

Agree with Andrew- although I too have noticed a much larger degree of shoe seperation since they stopped rivetting them. Much more so on infrequently used cars (I do have a few) -which makes for

interesting handling when the lining tries to spin & jam up in all sorts of fun places! Rarely lose the brakes mind -just a longer pedal & metal to metal! Yuk!

[garethj]

Drum brakes on a Mini are quite easy,and the old fashioned method works for me.

 

Clean and lubricate everything first,then put the drum back on,and press the brake pedal to centralise te shoes.

 

Turn the adjuster until you feel resistance,and can't turn it ( gentle pinch ) . The drum now will not turn

 

With one hand on the drum,and the other on the adjuster spanner,back off the adjuster again until the drum then begins to rotate freely again

 

Result should be a good pedal,and good efficiency

Pretty much this, if you've got a handy friend around get him to push gently on the brakes while you're spinning the wheel, that works well to centralise the brake shoes inside the drum. Once you've got the hang of it, sorted out the flaky rust and found where to put the axle stand without blocking your view it's usually pretty quick to do. But the first time takes longer.

[FredTransit]

You lot are all amateurs! I run un-servoed 11" drums all round, on a vehicle that can weigh just shy of 3 tons. It stops squarely and straight, no pulsing from the pedal, minimal squealing, and moderate pedal effort. All this from a vehicle built 42 years ago, with a braking system designed in 1955. It has manual adjustment, none of the new fangled "automatic" rubbish. I use it daily.

 

well done that man! Having no servo at all would frighten the shit out of me!!

[ashmicro]

I would like to meet the man who invented drum brakes, and shake him warmly by the throat.

[Albert Ross]

Really? I find them more efficient for the type of vehicle I own. After all, getting a disc covered in silt/mud only kills them quickly. Drums at least partially protect the friction surfaces in the gloop, so I keep a pedal and braking efficiency. The Discovery 3 handbrake is a disc/drum affair, but with an electric motor/cable actuation. At the launch demonstration by my local dealer (I worked there at the time) they had half a dozen of them running for three days in all sorts of crap. The second day, during "pre-flight" checks, someone noticed all the handbrakes were stuck on. Seems all the mud got into the unprotected mechanism of the parking drum, and baked onto the hot surfaces.... that cost a bit to sort. Modern isn't always better. Mine have a double lip between the backplate and drum, and drain holes around the periphery of the drum. Simple really, but very effective.

[Station]

I've always put disc brake conversions on cars because they're easier to do. I once had two drums seized and it took a day to remove them both.

[Albert Ross]

That's down to PO maintenance though. Regular, routine maintenance is the only way to keep on top of this kind of thing. My front axle belongs to my 1961 ex Military 109. The wheel studs are still peened into the hubs, it's running what I believe to be the original wheel bearings too. All because in it's early days, the vehicle was in a storage unit, that had a man, shouting at other men, who would then check all the oil levels etc. Thus was it's life until it was briefly used, and disposed of, late 1972, registered January 1973, then used by a rowing team in London. Hence the chassis corrosion at the rear. If a car is poorly serviced early on, it will be a rough one.

[michael1703]

I can get drum brakes to be the equal of disk brakes on the brake tester

 

Disc brakes have more consistent performance over drum brakes though

 

If I parked two wheels up a kerb overnight, next morning you can feel a brake imbalance as one side got the early morning moisture or previous nights rainfall, also on long motorway journeys in pissing rain you need to be cautious coming off on a slip road as drum brakes are less effective on first press

 

I bare metal the backplates and give them a coat or two of chassis paint or hammerite smooth and paint the shoes metalwork, use lots of red rubber grease on the wheel cylinder seals and copper slip the adjusters and get them nicely adjusted, some back plates have threaded steady posts to keep the shoe square on with the drum too

[Des]

Drums have to come off at least once a year for checking, if this doesn't happen then of course one day they'll fail. And rivets were dropped for bonding as it saved pennies and gave a slightly firmer feel to the pedal. The self servo effect of drums is nice, and a drum brake can be lighter than a disc equivalent, albeit only a gnats cockworth. I vote for drums, as discs are more modern so by default are newfangled lar-de-dar bollocks.

[dollywobbler]

I like both, but drums aren't the bane of all evil that they're often made out to be. As I said in the Voyager thread, too many cars don't really need discs at the back as they don't have to work very hard. So you end up with lots of seizures. MX-5s are notorious for rear calipers seizing and we've had issues with our VW Crafter minibuses.

 

I don't have a problem with no servo either. Absolutely fine on a 2CV and even our old H van could easily lock-up a wheel. A servo doesn't improve braking performance, just means you don't have to press the pedal as hard. I LIKE having to press the pedal hard. There are times when the stoppers on the BX are far too fierce.

[Albert Ross]

Re: MOT readings. Vectras of 2006/7 vintage weigh about the same as my Land Rover. Roughly 1700kg or thereabouts. The fronts on an average Vectra, with all the new-fangledness, ABS, dual circuit, servo discs etc, pull about 350-400kg as a max each. Rears, about 220kg a piece. Parking brake about 170kg each. This equates to an efficiency level of let's say 70% for service brake, and 20% for parking brake. My Land Rover, for all it's age, single circuit, non servoed drum brakes, pulls about 550 each front, and around 350-400 for each rear..... Making it about 105% efficient or more....... Go figure. The parking brake is measured a different way due to the type fitted, so can not be compared like for like. Other testers where I work are genuinely surprised when they see it on the rollers.... thinking I'm "cheating" for instance.... I just keep it maintained. The only difference is the fact I need to leave big gaps, due to pedal pressures involved. I think it makes me a safer driver.