Shortly , I'll possibly have to replace my rear shoes. First time I had problems with nearside failing MOT for non release, I stripped the lot down and found that the system pressurised and the pistons started to expand. I solved it by assembling the brakes and puling them in whilst slackening off the bleed nipple to relieve pressure. Next year, car failed on insufficient travel, so I knew that shoes were worn down. Problem was that I was also in that state and needed car in a hurry, so off to a fast fit place I'd trusted in past ,as garage couldn't fit me in for repairs for a few days. Price, reasonable. But I noticed that they stripped the brakes whilst waiting for parts to arrive. When I collected car ,I noticed brakes were poor, and put it down to new shoes. Two days later and brakes needed pumping. I took it back to MOT place for bleed brakes( I'd no faith in fast fit to cure) and MOT.

However on reflection, could this air in brakes/ piston moving out be a feature of ABS, and before working on brakes, should all reserve in servo be removed ?

Any comments ?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Not really, there should be no residual pressure in the system at all.

Pistons will move apart when you remove the shoes because there is a spring in compression inside the wheel cylinder. 

 

Thanks, Wino- Looks like it might be a  cable tie job when replacing rears then. Unless anyone has any further suggestions on keeping pistons in.

14 minutes ago, VWD said:

Thanks, Wino- Looks like it might be a  cable tie job when replacing rears then. Unless anyone has any further suggestions on keeping pistons in.

 

Did mine recently. The dust rubbers on the cylinders were enough to hold the pistons in place while fitting the shoes. On occassions where the pistons were trying to escape on other cars I've done, I wrap insulating tape around the cylinder then fit the shoes. The tape can be removed by easing the pistons in slightly with the shoes in place. Did this on an Astra the other day. Only works with flat(ish) faced pistons.

Thanks, TMB. I solved the problem on the side I had off to cure the rivet problem by reassembling the shoes etc and applying pressure to shoes, whilst slacking of the bleed niple a little to reduce pressure. On tip I did find on mine was to hold the horizontal spring on the shoes in place with a bit of string /tape untill the assembly was complete ,then remove when all is held in place before fitting drum .

But I'd suspect monkeys if FF place had shoes off too long and botched the job of getting the pistons back in.

Don't forget to check the plastic glide discs, part number 6N0609589. On mine they were in poor condition.

 

 

 

 

 

 

 

A +1 on checking the nylon pads.

I would also advise replacing the fitting kit, one of the pins failed through corrosion on my car causing the brake shoe to go out of position.

You can do the job without taking the rear hub off if you are changing the wheel cylinder bu tI would recommend checking the tightness of the wheel bearing nut retaining nut as this managed to work loose on the drivers side on one car and caused premature failure of the bearing.