Which slider pins do I need?

[Rickyy]

Going to give my sticky front brakes an overhaul. Pretty sure the slider pins are at fault as one seemed a bit bent last time I stripped them. MX5 parts are giving me the option of small and large pins.

Any quick way of finding out which ones I need. Due to a crap house and dark nights, I can't easily get the car in the air to check.

It's an R-reg Mk1, 1.8i UK model.

[Oldandslow]

From the looks of it to do both sides you need 2x large and 2x small. I.E. a large and a small for each side.

[Rickyy]

Oldandslow said:

From the looks of it to do both sides you need 2x large and 2x small. I.E. a large and a small for each side.

Came to that conclusion myself. Thankyou.

[pewe]

In my experience it's more likely constriction of the rubber pin carrier preventing the pin from sliding rather than a bent pin.

Tease the rubber sleeve out of the caliper housing - a fine, blunt screwdriver and some brake cleaning fluid will help - just be careful not to puncture the sleeve.
If they are punctured/split you really need new ones.

There are two things to do:-

1) clean the outside of the rubber (gentle scraping with a blunt tool may be necessary to take off caked rust) and then clean inside the rubber - again brake cleaner and cotton buds or similar - reason being there's often a build up of old, hardened grease inside the rubber which blocks the small hole at the outer end.
2) using an appropriate twist drill, hand held, clean out the hole for the rubber sleeve in the caliper casting - reason being the holes corrode, nip the rubber and stop the pins from sliding.A piece of thin string through the small hole helps pull the rubber gently back into place

When re-assembling use rubber or suitable high temp brake grease but deffo NOT coppaslip.

HTH.
Cheers, Pewe.

[Rickyy]

pewe said:

In my experience it's more likely constriction of the rubber pin carrier preventing the pin from sliding rather than a bent pin.

Tease the rubber sleeve out of the caliper housing - a fine, blunt screwdriver and some brake cleaning fluid will help - just be careful not to puncture the sleeve.
If they are punctured/split you really need new ones.

There are two things to do:-

1) clean the outside of the rubber (gentle scraping with a blunt tool may be necessary to take off caked rust) and then clean inside the rubber - again brake cleaner and cotton buds or similar - reason being there's often a build up of old, hardened grease inside the rubber which blocks the small hole at the outer end.
2) using an appropriate twist drill, hand held, clean out the hole for the rubber sleeve in the caliper casting - reason being the holes corrode, nip the rubber and stop the pins from sliding.A piece of thin string through the small hole helps pull the rubber gently back into place

When re-assembling use rubber or suitable high temp brake grease but deffo NOT coppaslip.

HTH.
Cheers, Pewe.

Fantastic post, thankyou. I've ordered the pins anway, but I will do as you say!

[Rickyy]

Just stripped, cleaned and greased the offending brake calliper.

Didn't order new pins in the end. Just used red rubber grease (is that any good? Was recommended in the motor factors)

Worked beautifully until I applied the brakes firmly, then the brake was sticking again.

The pad on the piston side doesn't seems very tight in the metal clips in the carrier. Is this normal or should they move freely?

The piston seems ok, didn't take much force to wind it back in.

Not much meat left on the pads, so going to order some new ones and retaining clips.

[Oldandslow]

Rickyy said:

The pad on the piston side doesn't seems very tight in the metal clips in the carrier. Is this normal or should they move freely?

Bit confused by this bit, seems contadictory. Assuming you meant that the pad seems very tight in the carrier. The notch that engages the pad/clips into the carrier can fill up with grit, rust and old grease. You can clean this out (diesel and a small wire brush is my method but even a scrape with a flat screwdriver will do), clean the clips too and for new pads I sometimes remove the powder coating if it is making the ends oversized. Apply copper slip and it should be a light interference fit i.e. not flapping about but moveable with finger pressure.

[Rickyy]

Oldandslow said:

Rickyy said:

The pad on the piston side doesn't seems very tight in the metal clips in the carrier. Is this normal or should they move freely?

Bit confused by this bit, seems contadictory. Assuming you meant that the pad seems very tight in the carrier. The notch that engages the pad/clips into the carrier can fill up with grit, rust and old grease. You can clean this out (diesel and a small wire brush is my method but even a scrape with a flat screwdriver will do), clean the clips too and for new pads I sometimes remove the powder coating if it is making the ends oversized. Apply copper slip and it should be a light interference fit i.e. not flapping about but moveable with finger pressure.

Typo, changed my wording without deleting the previous!

To confirm, they are very tight in the clips. I have taken them out and cleaned the notches in the carriers, but the clips looks to have been bent out of shape slightly. I had the prise the one on the piston side out.

I'll order some new ones with the pads and give it a go.