vauxhall astra brake caliper problem

[roofman]

The actual design of master cylinder seals is so fluid does not return into the piston assembly and ABS also. so forcing it back against the cup lips of the seals will not do them any favours at all.Plus iff you open the bleed nipples you can almost push the caliper pistons back with your thumbs which is easier than using G clamps ect....Ive done it this way for over 30 years but i also know guys who dont with almost no ill effects but i just dont like to tempt fate and keep mechanical risks to a minimum.

 

[pedrobedro]

We did the front brakes on an Astra and stuffed the master cylinder seals by pushing the pistons back. If you undo the bleed nipple you need to clamp the flexy pipe while you push the piston back.

 

[the snooper]

if you push fluid backwards, you will not be forcing it against the cups lips of the seal as long as the brake pedal is not pressed as the port that lets the fluid into the cylinder will be exposed and fluid will flow straight back into the reservoir, and If I did it will not be anywhere near the pressure you put on the seals when you brake

 

[doubleboost]

When you open the nipples the fluid just runs out
(this is how you bleed brakes on old cars) or use a pressure bleeder
The last thing you do is press the pedal down to the floor
The pressure seals are on the "open side" of the port when
the pedal is at the top

 

[waldershelf]

Modern cars with discs on the back almost all use a mechanical link in the calliper for the handbrake which operates on a coarse screw to maintain the normal handbrake lever position and number of "clicks" to operate as the pads wear. When pushing the pistons back into the calliper to fit new pads you have to screw the piston back up the screw if you don't you will knacker the handbrake mechanism. The first few brakes of this type I did I used all sorts of ingenious methods involving G cramps, pin spanners and other assorted lash ups all of which were pretty unsatisfactory, then I bought one of these http://www.amazon.co.uk/XTools-Serv...=1404159732&sr=8-4&keywords=brake+rewind+tool and haven't looked back since. If you are a tool snob you can pay several times the price and get exactly the same kit in a different coloured box with a "brand" name on it.

 

[Wallace]

Does that kit have left and right hand threads?

 

[waldershelf]

Does that kit have left and right hand threads?

Yes it does, I have yet to find a set of brakes that the right combination of bits out of the box wont do the job.

 

[gordon stephenson]

Always had to open the nipples on my land cruiser,otherwise the ABS light on the dash would come on and not sort it self out for up to a week.