9 replies to this topic

[MaximMini]

Hi Everyone,

 

I have some questions regarding the reconditioning of the standard 8.4" brake callipers (see my built thread).

 

Firstly, according to the instructions that came with the reconditioning set, I understand the sequence of reassembly as follows:

 

1) place new fluid seal in the corresponding groove

2) press in piston until approx. 8 mm is left protruding

3) fit new wiper seal to new seal retainer

4) slide wiper seal assembly over the piston and press home squarely.

 

Is this the recommended way to reassemble the callipers or do you have any better ideas?

 

And secondly, what the is the torque specification on the two bolts that attach the two halves of the callipers together?

 

Thank you very much for your input ..

 

[cian]

The way I do them is fit the seals / retainer then fit the piston, be careful fitting the retainer it’s easily damaged make sure the calliper edges are cleaned well of excess dirt and rust

I do them for £60 a calliper and that’s AP bodies

[nicklouse]

The way I do them is fit the seals / retainer then fit the piston, be careful fitting the retainer it’s easily damaged make sure the calliper edges are cleaned well of excess dirt and rust

I do them for £60 a calliper and that’s AP bodies

same and don't bother splitting the calipers. found a useful tool for pressing the retainers back in.

http://www.theminifo...-out/?p=3540406

[Spider]

I always split the calipers to overhaul them. It's not recommended in the shop manuals only because in the standard overhaul kits, the Bridge Seal and New Bolts are not included. AP have said it's OK to split them, if these parts are replaced.

 

I must admit though, I've done countless Calipers and re-used the bolts without issue, but I would strongly recommend to follow the manufacturer's advise. Since receiving that, I now replace the Bolts as well.

 

Splitting them I find allows for not only easier cleaning, but there are loads of places where the dead sea resides within the Calipers than unless split, will get missed, you just can't otherwise get to them, eg, around the Bridge Seal for one.

 

I've always fitted the Seals (with Rubber Grease), including the Dust Wiper and Retaining Ring, slapped some Rubber Grease on the face of the Seals and between the lips of the Dust Seal, then pressed the Pistons in, then the Bridge Seal (greased with Rubber Grease) before putting the two haves back together.

 

I have a torque figure for the bolts - somewhere !

[Spider]

I have a torque figure for the bolts - somewhere !

 

60 ft/lb for the 8.4" type Calipers.

[Ade-Cooper]

Honestly I would go to your local parts supplier - I brought a pair for around £100 with trading in my old units (which I destroyed the bleed screw threads) 

[jime17]

Honestly I would go to your local parts supplier - I brought a pair for around £100 with trading in my old units (which I destroyed the bleed screw threads)

Why?

It's a straightforward job.

For the record. I pump the pistons almost fully out whilst the caliper is on the car using the brake pedal and replace all the seals etc before sliding the pistons back in. As someone else said.

I've also split the caliper before now.

Edited by jime17, 14 March 2019 - 07:58 AM.

[MaximMini]

Hi,

Thank you very much for all your valuable information on this topic.

From my point of view these brake callipers are serviceable units and the correct service parts and know how provided, there is no reason to not try.

I will report my work results in my dairy.


Cheers

[Cooperman]

Like Chris, I also always split the callipers when doing this. It certainly makes it easier to be sure the callipers are fully cleaned and it is easier to fit the wiper seal, which can be a b^^^^r of a job.

 

Always fit a new rubber seal between the two halves, but I have always re-used the bolts, with Loctite, and never had any issues.

 

Absolute cleanliness is the key, as will all hydraulic system work.

[Ade-Cooper]

 

Honestly I would go to your local parts supplier - I brought a pair for around £100 with trading in my old units (which I destroyed the bleed screw threads)

Why?

It's a straightforward job.

For the record. I pump the pistons almost fully out whilst the caliper is on the car using the brake pedal and replace all the seals etc before sliding the pistons back in. As someone else said.

I've also split the caliper before now.

 

 

Had to drill out the old screws and fit bigger nipples - resulting in a very bad fit. Probably my own fault but machine shop did the drilling and tapping thus resulting in a leaking caliper. just one of my many mini issues lmao!