Replacing discs

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Tue Mar 01, 2016 5:40 pm

Merlin wrote:
newkid wrote:retaining screws on the discs can be a pain tho
http://www.ebay.co.uk/itm/14pc-1-2-Driv ... SwNSxU92TI

Post by **Merlin** » Wed Mar 02, 2016 9:06 am

newkid wrote:
Merlin wrote:Make sure you have a way of pushing the caliper piston back in, a caliper winding tool, a large adjustable set of pliers or a big G-clamp Other than that should should be fine with regular tools.
Screwdriver

You must be good with a screwdriver if you and get the front piston back in

Yeah a big flat head is sometimes good for the rears.

Post by **newkid** » Wed Mar 02, 2016 9:33 am

Merlin wrote:
newkid wrote:
Merlin wrote:Make sure you have a way of pushing the caliper piston back in, a caliper winding tool, a large adjustable set of pliers or a big G-clamp Other than that should should be fine with regular tools.
Screwdriver
You must be good with a screwdriver if you and get the front piston back in Yeah a big flat head is sometimes good for the rears.

there's a way to do it. @vanzep bb1 was done this way

Post by **Merlin** » Wed Mar 02, 2016 9:45 am

Share the technique!

Post by **vanzep** » Wed Mar 02, 2016 11:34 am

If i remember right its just use a flat blade as a pry bar between the carrier and the piston
TBH G clamp is easier tho

Post by **newkid** » Wed Mar 02, 2016 12:03 pm

Merlin wrote:Share the technique!

Yea. Use old rear pad, disc. Remove front anti rattler. Pry with old disc. All the while still on car. Easy to push it back then.

alinton · Post by **alinton** » Thu Mar 10, 2016 5:55 pm

Discs arrived and done, no probs with the retaining screws on the offside, as there weren't any!

The nearside had two, though.

Next: Rears!

alinton · Post by **alinton** » Fri Mar 18, 2016 9:55 am

Yesterday I replaced the rear discs and pads. The near side rear disc looked pitted and a little rusty, I discovered why!

The pins that connect the calliper to the carrier had seized, which I guess meant that only the inner pad was doing anything.

It was a bugger to free up, I removed the whole assy from the car and worked on it in the bench. Eventually after lots of pulling and twisting the pins popped out. I cleaned them off with alcohol, and the holes, regreased it all and reassembled so that they slid freely.

Reassembly was ok, except that it was difficult to get the piston lined up properly so the little spigot on the pad lined up with the cross shaped recess on the piston. Why is the rear like that, but the front pistons hollow?

The offside calliper carrier wasn't seized, but was a bit stiff, so I reconditioned it anyway.

The first side I did took 2 hours, the other side 30 mins!

Post by **indigolemon** » Fri Mar 18, 2016 10:30 am

The rear pistons are both hydraulically and mechanically operated, as they contain the handbrake mechanism. The pistons need to be wound back in - forcing them straight back can potentially damage the handbrake mech.

alinton · Post by **alinton** » Fri Mar 18, 2016 10:50 am

That explains it. My calliper compression tool has little spigots that stick out, and it did wind the piston back in by default.

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