Disc Pad or Caliper Assembly Issue 1.9 140bhp

[Paul Weller]

Hi All
I am doing a full front end suspension and brakes refurb and the new (solid) discs and pads combined thickness is bigger than the gap in the callipers!
Pads overall thickness is 17.8mm each. I have looked online and those quoting a thickness vary between 20mm and 16.8mm.
Does anyone know what it needs to be to fit or have I got a piston return issue? I am using a G clamp to drive the pistons back so should be OK?
Paul

 

[Sean d]

Have you split the calipers from the carriers as this is a must

 

[Brian4]

When this pistons are fully back into the caliper the part that pushes on the pad should be about flush with the carrier. If it won't go back that far probably the pistons are rusty and binding on the caliper.

 

[Paul Weller]

When this pistons are fully back into the caliper the part that pushes on the pad should be about flush with the carrier. If it won't go back that far probably the pistons are rusty and binding on the caliper.

OK thanks for that Brian, the piston is about 3mm proud, so must be rust behind the bellow binding.
Seen new 1/2 calipers with the piston on ebay from APC for around £50, any good?

 

[Paul Weller]

Have you split the callipers from the carriers as this is a must

Yes Sean I split the two halves down as everything was coming off anyway. Once I got the suspension arm taper joint free on the swing arm to crosmember anyway!

 

[Paul Weller]

When this pistons are fully back into the caliper the part that pushes on the pad should be about flush with the carrier. If it won't go back that far probably the pistons are rusty and binding on the caliper.

Yes you were right Brian. The other side piston went in deeper and I could just get both 17.8mm pads to fit.

 

[Brian4]

I guess the drivers side caliper wsearch the one you couldn't get to fit.
The difficult caliper will seize in soon probably after a few drives in the rain and it has been sat for a while. You will need to put new pistons into the calipers or get refurbished calipers soon.

These are my new and old pistons. Once you have pushed them back with new pads the rusty bit of the piston is against the caliper body and rest onto it.