Std. Front calipers - rubber boot retaining spring and sticking pistons

[Myles]

I remember that they were a pain in the arse to replace from the time I tried it (probably two years or so ago) - a major exercise in dealing with frustration.

 

I ended up replacing the boots and spring retainers -and ISTR that they went back on much more easily than the old ones - but I can't remember if I'd learned any special tricks to get the spring to seat without piercing the boot or sliding off.

 

Any hints out there - or is it just easier with new boots? A local up here in Scottingland has perished boots - which we remove at one of Lawrences Tuesday fettling sessions. Three went back on OKish, but the fourth was a bugger. And Paul has to do it all again when he gets new boots... 😳

 

While we're on the subject - the reason for removing the boots was to investigate seized/sticking pistons. Both calipers had one sticky piston - and we pumped them partway out, cleaned up any obvious corrosion, lightly greased them and worked them back in.

 

Short of stripping the calipers entirely, is there anything else that can be done to help them while Paul has the boots off next time...(i.e. is he wasting his time fitting new boots if he is likely to need to refurb the entire clapper???)

 

Project Scope-Creep is live...

 

Alcester Racing 7's Equipe - 🙆🏻™

 

Alcester-Racing-Sevens.com

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[caligarinet]

Thanks Myles, your help was much appreciated.

 

Trying to find a place for a replacement seal kit, anyone have a recommended supplier?

 

 

 

Scottish Sevens

 

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[DohNut]

 

Greased 🤔

 

Does grease or any hydrocarbon type stuff attack the seal?

Will it not also be adversley affected by temperature?

I was lead to believe this was a bad thing

 

I eased the fitting of my pistons by smearing a bit of brake fluid on the seal when it was re-fitted and generally smear a bit of brake fluid in the area between the fluid seal and the dust seal - the idea being that if brake fluid was there then air and water were not.

 

Imperfect because the fluid will attract water and it is hard to tell if a seal is leaking.

 

Nick

[caligarinet]

Nick,

 

We used this stuff...

 

Red Rubber Grease

 

also made by Castrol

 

CASTROL GIRLING RUBBER RED GREASE

 

I was advised to use it just on the leading edge of the piston (ie where it is in contact with the rubber seal.)

 

Is this recommended practise?

 

Scottish Sevens

 

Edited by - caligarinet on 7 Jun 2006 10:57:12

[DohNut]

 

OK - special rubber grease

I like the idea of it especially of lubricating the outside bit of the piston assuming it is happy getting up to brake type temperatures.

 

I wonder how useful that would be assembing A frame bushes etc 🤔

 

[caligarinet]

>

 

a quick google, suggests its got quite a few different uses..

 

although, be careful what links you click on, especially when searching for red rubber grease

 

purchased seals from Caterham, although state they don't come with circlips

 

 

 

Scottish Sevens

 

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Edited by - caligarinet on 7 Jun 2006 11:47:44

[caligarinet]

Myles,

 

Received seals from Caterham today.

Repair pack comes with all the seals incl, fluid seals, dust covers, circlips, and what I assume are bleed nipple covers.

Also each pack contains an axle set of seals, so I've ended up with a spare set as well.

 

Wonder if the rear calipers use the same seals.

 

The seals looks much more substantial than the ones we were playing around with on Tuesday, so hopefully I'll find it a bit easier tonight.

 

will let you know how I get on.

 

Paul W

 

PS, if anyone has any further tips on fitting these, it would be very much appreciated.

 

[Crudders]

I wonder how useful that would be assembing A frame bushes etc?

 

Never go near the A frame bushes without it! Also a bit handy for steering column bushes

 

I also bought the Millers red rubber grease from Frost as most most motor factors only seem to sell the stuff in tiny tubes or sachets - about enough to do one brake job ☹️

 

Edited to add - I've never dismantled the Triumph front calipers and I don't have rear discs, but I'd be very surprised if the rear Ford sourced calipers have the same seals. As for tips, I'd just say use LOTS of red rubber grease

 

Crudders

 

Edited by - Crudders on 8 Jun 2006 13:57:47

[caligarinet]

Crudders,

 

I actually got mine direct from Miller's for 2.98 for a 500g tub.

Reckon it will last me a lifetime!!

 

Myles,

 

What can I say, replaced the dust seals tonight, 15 mins each side, on my own.

Nothing to do with my skill, just the job is 1,000 times easier with new rubbers and springs.

 

The rubber seal, was tight and locked in place on the piston when it was pushed out.

Then pushed the piston back in, and the rubber seated itself on the caliper.

 

The spring I then put on the opposite way round from our attempts last night.

ie. put the break in the circle on first, and then worked back from there, and pushed it on.

this meant you were just pushing down on the spring, and the open-ends just naturally opened up and your thumbs travelled around the spring.

 

The springs, weren't as rigid as the old ones, and had a lot more, well...springyness.

 

Anyway, not the most techincal description, but quite happy to give a demo next time, got it sussed 😬

 

Scottish Sevens

 

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