Front brake shoes

Post by **winger300** » Wed Oct 15, 2003 11:44 pm

Hello,

Following my recent MOT i was advised that my front brake shoes were worn, and will need replacing soon.

My car is a 1955 splitscreen, it has a 1098cc engine, but i think it still has the 7" front drums.

I have a few questions about the procedure for replacing the shoes.

Do i need any special tools for holding the pistons in the cylinder?

What other components should be replaced along with the shoes?

Do i need to grease anything? and will Lithium grease do?

What torque setting do the wheel nuts require when putting the wheels back on?

Post by **rayofleamington** » Thu Oct 16, 2003 12:06 am

I would be surprised if the mot centre actually took off your wheel, (and maybe the drum) to inspect the brake shoes.
everything is possible though!

Minor brakes do not self adjust (ok - standard minor brakes don't.. before anyone comments on their disk brakes or Ford rear brakes..)
Therefore if the car isn't very well serviced yet, they may just need adjusting.
If they need replacing then you don't need special tools, but a coulple of big screwdrivers will help.

An experienced eye can see the thickness of shoe when looking through the adjuster hole. If you've not had them apart before it is worthwhile to get the drum off anyway! Then check the shoes to see their condition. If they are the riveted type I'd bin them regardless.
also check the drum carfully - riveted brake shoes can wear grooves into the drum (when the shoes are worn the rivets will rub on the drum)
A grooved drum is more prone to overheating (brake fade).
Also if the drum is badly corroded (the outside ring starts to dissapear), then it is also adding to the overheating problem.
As well as the drums the brake return springs should be inspected - they can fail if they are heavily corroded.
With the shoes off, check that the pistons slide easily in the cylinders. it they are sticking, they will need to be removed and cleaned up (and the inside of the cylinder - but with a lot of care)
You should use a brake fluid compatible grease on the pistons. Lithium grease like most greses wil be mineral based and that wrecks brake fluid seals. I have used mineral grese on wheel cylinderr pistons in the past and got away with it but it is not very clever - especially on the brakes. If they are cleaned up they should work without grease anyway!

You may well have the 7" brakes - it's a common oversight when upgrading to a 1098. The 8" brakes are noticably better.
(the 8" drums are about 8.5" on the outside, as the 8" is on the inside)

If your 7" drums are poor, you may as well buy some 8" drums instead. Then you just need to get hold of some cheap second hand 8" backplates and replace the 7" backplates. Fitting may best be a garage job unless you want to repipe the brake cylinders.
Check their hourly rate though as it's not a 5 minute job.

Post by **Kevin** » Thu Oct 16, 2003 12:39 am

One thing you will need to do is slacken off the adjusters a few clicks to remove the brake drums.
I cant find a torque setting for the wheel nuts but as long as you use the minor wheel brace you will not overtighten them.

Post by **57traveller** » Thu Oct 16, 2003 8:32 am

Hello winger - 36 ft lbf rings a bell for the wheel nut torque, that's for Minor 1000 though, don't know if the earlier cars are different. But I would agree that using the Minor wheelbrace will be o.k. Just don't overtighten.
Elastic bands of the correct size are adequate to hold the pistons in the brake cylinders, place them outside where the shoe end sits - you are able take them off then!
Maybe best not to use any grease in your brakes but possibly just a light smear will be alright.
Your insurance company may not be too happy (in the event of a claim) if you still have 7" front brakes with a 1098cc engine.

As suggested earlier, why not upgrade to 8"?

Post by **winger300** » Thu Oct 16, 2003 10:48 am

Thanks for all the advice.

I tried to take a look at them this morning, but i cannot for the life of me get the wheel nuts undone!

The minor wheel brace i have is an L shaped one, and it doesn't really allow for standing on it. I tried a ratchet handle too, but they wont budge. I do recall the guy at the garage where i got my tyres replaced using a 2-foot extension bar, so he's probably tightened them up to about 100 ft lbs!

If i replace the brake drums, i'll have to replace the hubs too, since they old ones are one peice backplate and drum.

I dont have any problems braking though, they are usually pretty keen.

Post by **Kevin** » Thu Oct 16, 2003 11:26 am

Go back to the garage and ask them to slacken off the wheel nuts, and then make sure that they are done up with the minor wheel brace.
The other way is to borrow a piece of scoffolding tube to put over the end of your ratchet or tommy bar to increase the leverage.
Are you sure your drums and backplates are one piece ? you would not be able to renew the brake shoes if that was the case.

Post by **lowedb** » Thu Oct 16, 2003 1:07 pm

Drums and hubs in one piece, rather than drums and backplates is what he'll mean. Same on my '53 SII.

If it were drums / backplates in one piece, I think the wheels would have some difficulty turning, let alone changing brake shoes.

I'm going to have the same Dilemma as I have a 1098 to fit. Plenty of time to think about it, though!

Post by **winger300** » Thu Oct 16, 2003 4:50 pm

Here is a picture of inside my brake drum,

How much is left in these shoes?

Post by **57traveller** » Thu Oct 16, 2003 4:56 pm

It looks as though they're getting close to the rivets and just about ready for changing. If they wear to the rivets your drums will become scored.
Now you've got this far, why not renew them anyway?

Post by **rayofleamington** » Thu Oct 16, 2003 6:24 pm

ooh - axle stands and trolley jacks! Not slumming it then ;-)

Am I bieng a bit slow here... The hub looks like the morris 1000 item and both the 7" or the 8" drum should fit (not at the same time

)

However I dissassociate myself from the original comment - maybe they did check your brake shoes!

Post by **winger300** » Thu Oct 16, 2003 7:14 pm

yeah, the garage replaced the wheel bearings and brake hoses, so i guess they would have had a good look at things.

It does look like the hub and backplate are seperate, i measure the inner diameter of the drum, and it is 7".

Back at home i have an 8-inch drum (re-conditioned) , backplate and new 8" brake shoes (all o/s front wheel), so i guess i should only need a Left hand drum assembly. Is this correct?

Can i use my existing cylinders? and can i do it all without having to re-bleed the brakes?

Post by **Willie** » Thu Oct 16, 2003 7:22 pm

You MUST fit the 8" ffront brakes to go with your 1098
engine so that it conforms to the factory specification
(for insurance purposes). The point to remember is that,
when you fit the 8" backplates, they are handed, marked
L and R and if you fit them on the wrong side you will finish
up with lousy brakes going forwards and excellent going
backwards!!

Post by **winger300** » Thu Oct 16, 2003 7:28 pm

ok, which parts do i need to purchase? and which parts from the 7" drums can be used on the new 8" ones?

Post by **Willie** » Thu Oct 16, 2003 7:40 pm

Well, when i carried out this upgrade on my car i used
NOTHING from the originals since the drums are bigger,
the shoes are bigger and I took the opportunity to fit
new wheel cylinders while I was at it! My car was a '57
so it had the later hub assemblies. I am not sure what
assemblies you have? One thing, your car has the early
type of Master Cylinder which has a slightly larger bore
than the type fitted by the factory to the 8" front brakes.
Do not worry about fitting the later type master cylinder,
in my experience you will notice no improvement so save
your money and effort.

Post by **rayofleamington** » Thu Oct 16, 2003 8:18 pm

As far as I'm aware, the 7" wheel cylinders can just be fitted on the 8" backplate. However you will almost defiantely have to replace the short connecting pipe that goes between the 2 cylinders.

I would also recommend to leave the original master cylinder. It will not improve the performance of the brakes, however it may make a small minor effect on how hard you have to press the pedal.

Post by **brixtonmorris** » Tue Oct 28, 2003 4:39 pm

you can tell a lot from pressing the brake pedal and watching those gauges carefully

Post by **Kevin** » Tue Oct 28, 2003 4:54 pm

watching those gauges carefully

Sorry I am a bit confused could you expand a bit

Post by **brixtonmorris** » Tue Oct 28, 2003 7:02 pm

the brake test gauges. good mot testers understand the slightest movements on the pointers.

Post by **rayofleamington** » Tue Oct 28, 2003 7:28 pm

they check right and left brakes at the same time to see if they are balanced. It's not always a failure as there is some tolerance allowed. On a minor unbalanced braked is often a sign that you have a sticky piston.
Watching the gauges carefully you should be able to tell if the performance is slightly different - if so it never hurts to have a good look at the drums/shoes/adjusters/cylinders.

The rough way to check is drive on an empty road and do an emergency stop from 20mph without your hands on the steering wheel. If it stops in a straight line then repeat at 40mph.
If you have bad brake balance then the car will slew sideways.
That's always a good check when buying a cheap car (or any car!)

With your hands on the wheel you can naturally compensate for it without even knowing it.

Post by **brixtonmorris** » Tue Oct 28, 2003 7:30 pm

with a minor, the distance travelled by the pedal gives an indication of the distance travelled by the shoe. if the brake shoes are new there will be little pedal travel. there is no auto adjuster. so as shoe wears pedal travels more until manual adjustment is carried out. so it get adjusted but do they all get adjusted to the same pressure. the gauge revieals that. the mot tester told winger 300 that they would need replacing soon. he new there was a fair amount of travel going on