Don't do it!

[JJDraper]

I was having a little difficulty getting the new pads into the rear calipers, having fully retracted the pistons so I thought "why not tap them down a little". Bad idea.. the material is good in compression but shear strength of a weetabix.

In addition, I note that the metal plate has four depressions/holes which allow water to enter the space at the head of the pistons, causing rust & muck to collect - why?

Lesson learnt. Do more clearing out of the pad lands - even so they are a really tight fit.

Jeremy

[davidc]

yep, did same with my fronts!

retracted piston as far as would go and though a bit of persuasion would do it.

turned out piston was corroded so wouldn't fully retract so ended up rebuilding calipers

[denicholls2]

In addition, I note that the metal plate has four depressions/holes which allow water to enter the space at the head of the pistons, causing rust & muck to collect - why?

The depressions on the backside of the pads could be filled to eliminate your concern, but they are surely there because it was cheaper to stamp than cast the backplates. The bumps on the other side are the goal; they provide lateral strength to the bond between pad and caliper, acting like the pins on your rims. I bet they also squeal nicely when the pad wears through.

[theelanman]

I worked in R&D for Ferodo
that should never happen.......
don't forget that there is shear force applied when the wheel/disc is still rotating.......
that is the worst pad Ive ever seen..........and most of the terrible ones were the Chinese copies
we used to buy other pads.....just to put them through our own testing.........
I will only ever buy pad with Ferodo on them.....having seen what I have seen and learnt alot...

[theelanman]

also theyre missing the anti squeal shim.....which should also cover the holes......

[USA64]

So origin, brand, and seller would be the best information from this post.

[JJDraper]

EBC brand - Ultimax 2 from well known UK supplier. Made in the UK...

As far as I'm aware the rear pads do not have shims (workshop manual).

Jeremy

[RichardHawkins]

Elanman,

Excuse me going a bit off topic, but I have wondered for years, how do anti squeal shims work?

Richard Hawkins

[JJDraper]

A little looking has not shown many alternatives for EBC in the UK. I did find a set of 'sintered' pads for over 165 pounds, but these are a little rich for my taste, and no good for road use I suspect.. Sorry no Ferodo parts to be had.. They don't seem to cater for classics. The only reasonable alternative seems to be EBC Green Stuff for a few pounds more..

Jeremy

[jono]

I have to say I've been quite happy with EBC Greenstuff on my plus 2. I had to fettle the metal plates a little to get them to fit but they have worn well, create little dust and have enough bite for fast road use. Cheap too.

[theelanman]

from what I know EBC get their pads made in the USA and UK......
even so....these should never have come off the back plate........its as if the bonding material is missing......although by the colour and texture its as if its not been pressed at the right temp
you can usually see two discernible layers.......the bonding layer and the wearing layer.......
the shim is nothing special.....is a damper to stop the pad rattling around in the caliper and also a soft bed for the piston to push on so that you get full face contact wit the pad and the disc........
when a pad doesnt sit flush with the pistons on the back and the disc on the front that when you get squeal as one of the edges it vibrating between the two faces....and it only needs to be microns

[theelanman]

brake pads are very much a dark art
we had terrible problems with a pad for the ford focus (UK mid range)
the standard mix was being made no problem........
all of a sudden the Japanese had their Tsunami in 2011.....and they in that region were the supplier of one of the clays that were included in the mix.........
once we'd used our stock we had to use the same 'ingredient' but from a different supplier.......it came from SA as I recall
this was added in the mix was tested.......and it failed.......we tried over the course of a week to rectify the mix but couldnt.........we had to change over to a different mix.........
the strange thing was that when the supplier came back on line......we re made the mix.....and everything was fine......
so the same chemical but from a different part of the plant cause a completely different outcome.......
but as with any change we tested it first and proved it failed so it never went out.......
not sure I can say the same for your pads.......

[RichardHawkins]

Elanman,

Thanks for the reply and explanation.

I worked in the chemical industry, where a lot of our vessels were brick lined. One day whilst in discussion with our brick supplier he said something similar about clay "it's a naturally occurring material, and when the quarry is worked out the brick is made from a different clay and the properties change"

Richard Hawkins

[JJDraper]

As an aside, I was going over my maintenance records and find that the rear pads I was replacing had only covered 13k miles, on new discs. Fairly even wear on both pads, both sides, but almost down to the metal - sub 1mm!

The discs are pretty scored, but serviceable. Perhaps that's why Lotus tried a 'bodge' to fit the shroud at the rear of the +2 - to overcome accelerated wear due to assorted road crap being thrown onto the discs/pads.

Fronts last longer, but need to be disassembled and cleaned annually to keep the pads moving smoothly on the pins. Keep a supply of fresh pins and clips..

Jeremy