Hi, I have a 1997 Fiat Punto Mk1 which failed its MOT on 1 rear brake binding. It is only binding in particular places rather than the whole thing. I got a mechanic to replace the drums and shoes, and it still happens! I have read up and it says it could be a warped drum, but as it has new ones that can't be the problem... and I can't find any other reason! I don't think its the handbrake as its not binding all the way round. Anyone any idea what it could be? Thanks

Did they replace the brake cylinders too?

Nope, just drums and shoes. My bf says, why would that cause high spots? He said to me that if was that, would it not be binding all the time?

To add insult..... the mechanic has robbed my brake shoes, and left the crappy ones on... so this may be the brake shoes still causing this fault as the mechanic decided to rob mine! I'm going back tomorrow to demand them back!

If the cylinder has seized open it will cause the brakes to rub. Take the drum off and push the top of the shoes into the cylinder and press the brake pedal while someone observes if it's moving or not (more importantly returning fully)

Only push pedal ONCE with the drum off or the piston will come out of the cylinder completely!

Biggest problem with Punto series 1 & 2 rear brakes are the self adjuster mechanisms which don't work reliably.

There are two types of adjuster: one built into the shoes and one which isn't.

The built in ones fail after only a few years.

FIAT has brought out a modification kit which replaces the who set up: shoes, springs and self adjusters to the reliable type which shows that they must have had problems.

Had shoes changed now properly and its still doing it!

Boyfriend says.... he doesn't think that its an adjuster because they seemed to have slackened off with the new shoes on.

How much do you think it would cost me at Fiat to just say find the problem and tell me what it is? Has to go back to Fiat for a recall on the brake pipes. I'm getting to the end of my tether with it because we tried handbrake, new drums and shoes, and we just had to take an angle grinder to a locator plug cos mechanic put it so tight we couldn't get it off.

I will get him to look at the cylinders after work tomorrow. We just had a look in the dark, and he said it looked okay, but he isn't a mechanic.... so I'll get him to do it again.

Could it be the bearings? That was another idea

Or the Back Plate? Bf said that would only be wrecked in an accident, and not been in any sort of major accident.

If the cylinders are leaking there is no point fitting new seals just fit new cylinders.

The hand brake levers can get sprained so the hand brake lever travels a long way and doesnt do much. New drum levers are cheap to replace.

When you fit the drum have a friend press the brake pedal as you tighten the screws. But they are only retainers. If its still suspect fit the wheel and do the same pedal trick as you tighten the wheel bolts.

If the bearing is loose the wheel will wobble top/bottom, easiest tested with the wheel attached.

Okay, so its not the bearings as wheel isn't rocking back/forward or left/right

Cylinder is fine, no leaking

Backplate not bent

New shoes, so new adjustor

New drums, not warped drum

Not Handbrake

We are truly at a loss, what else could it be?

Binding in one or two spots rather than all the way round suggests a rotating part, hence warped drum was the first suspect. Even though it's new, you could try swapping between wheels.

However, no drum is perfect so if something else is causing the problem and pushing/holding the shoes out, they would hit the high spots of the (imperfect) drum first. You could prove whether it is the shoe catching the drum (as opposed to something else causing the bind) by assembling without the shoes (at risk of stating the obvious, don't pump the brakes without shoes on).

If you decide that it must be the shoes catching the drums, you might want to check that the piston isn't tight in the cylinder. I've had duff seals do this (and even rust inside cylinders) with no signs of leakage.

Maybe double check that shoes and drums are the correct size. Next to consider is whether the shoes are sitting in the right place. Shoes need a bit of wiggle room to deploy so look around for rust that could impede this. It's OK to put a smear of copper grease on surfaces that rub/touch (e.g. edge of shoe to backplate) but be careful not to overdo and not to contaminate the shoes or drum contact faces (I'm in the realms of obvious again).

Finally, don't give up - this is a very fixable fault!

red

When the shoes are taken off and drum on then doesn't bind. What does this mean? Its the shoes? Its only partial when put locator plugs or wheel nuts on with shoes on.

Also round the inside drum are signs of heat wear, only driven down road in it, literally!

Shoes and drums are correct size.

Were all the springs replaced with the shoes? One of the springs may have stretched too much, not holding the shoe in far enough

No they weren't! I will try that to see if it works. Completely didn't think about the springs!

Didn't work

The only thing left to change is the wheel bearing. If it feels tight or knotchy it could mimic a binding brake.

Generally its better when doing the rear brakes to replace everything shoes, springs, clips, cylinders, drums and handbrake cable; most likely however either the self-adjuster on the back of the rear shoe has been inadvertently nudged forward so just remove the shoes and push it back; the reason it appears to be binding in just 1 or 2 places is that the shoes have been unable to centralise; also the handbrake cables are very vulnerable on the Mk1 and are often clobbered thus nipping the inner cable and causing the brakes to bind. Do not take it to Fiat unless you have a very deep pocket.

It has been in the garage for the last 4 days, and they say that they have fixed it! And I am waiting to see what was wrong!

Turns out, they don't know what it is, but they think its the rear axle. They have ground down my brake shoes and all is working.... cost me 70 frikken quid though!