classic car forum header
Classic cars forum & vehicle restoration.
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
Register     Posting Photographs     Privacy     F/book OCC Facebook     OCC on Patreon

Splitting Brake Calipers
Post new topic   Reply to topic    Classic cars forum & vehicle restoration. Forum Index -> Mechanical Restoration
Author Message
UKdave2002
Guest





PostPosted: Thu Jul 12, 2007 12:53 pm    Post subject: Splitting Brake Calipers Reply with quote

In many workshop manuals there is a very clear statement along the lines of; “Under no circumstances should the brake caliper be split” …why?

Splitting makes servicing calipers so much easier, it’s not complicated; there is usually an “O” ring which may be as old as the car and would benefit from being replaced. Yes you have to re-assemble the calliper correctly under scrupulously clean conditions, torque the bolts correctly and check it all seals and hold pressure, but this is no different to working on other components in the hydraulic system.

So why the dire warning ?

Dave
Back to top
Uncle Joe
Guest





PostPosted: Fri Jul 13, 2007 4:04 pm    Post subject: Reply with quote

It was pointed out to me a few years ago, that 'scrupulously clean' in terms of hydraulics is not the same as what most people mean by scrupulously clean.

The minimum air quality in the room has to be what is known as 'Hepa clean,' which I understood to be the next step down after sterile.

I wish someone would explain the reasoning behind this better to me!

UJ
Back to top
magic9r



Joined: 13 Dec 2008
Posts: 33

PostPosted: Sun Dec 14, 2008 5:55 pm    Post subject: Reply with quote

Given the amount of crap that gets pushed through the caliper from deteriorating systems plus that which forms in a caliper that's total BS.
The two main reasons are:-

1 - No one will advise you to split them because they don't want the liability for what might happen if they came apart again in use and they cannot assess your competence to do the job.

2 - The industry has a vested interest in selling you a new or recon part, some places are now refusing to sell caliper service kits on liability grounds but will get you an exorbitantly expensive exchange unit, undoubtably precision built in a clean room by some 18 year old gimp with a vocational qualification and neat clean fingernails.

Go figure,
Regards,
Nick
Back to top
View user's profile Send private message
PAUL BEAUMONT



Joined: 27 Nov 2007
Posts: 1281
Location: Barnsley S. Yorks

PostPosted: Tue Dec 16, 2008 1:56 pm    Post subject: Reply with quote

I worked for Lucas Girling for several years and calipers were assembled on a standard production line, not in some clinical clean room. The O'ring replacement makes sense, so might replacing the bridge bolts with new high tension ones, but so long as you use the same care that you would for say a head gasket, I see no reason why a caliper should not be dismantled for servicing
Back to top
View user's profile Send private message
TriumphDriver



Joined: 22 Jan 2021
Posts: 11
Location: Northern Ireland

PostPosted: Sun Apr 18, 2021 5:44 pm    Post subject: Reply with quote

Does anyone know the torque they should be retightened to?
_________________
Still learning after all these years...
Back to top
View user's profile Send private message
peter scott



Joined: 18 Dec 2007
Posts: 7113
Location: Edinburgh

PostPosted: Sun Apr 18, 2021 5:50 pm    Post subject: Reply with quote

I don't know what rating of high tensile steel they are made of but the table here should help.

https://www.grampianfasteners.com/files/95b2c19b-1d29-4624-abdf-0813df2db3ac/Torque_Settings.pdf

Peter
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon
Back to top
View user's profile Send private message Visit poster's website
alastairq



Joined: 14 Oct 2016
Posts: 1950
Location: East Yorkshire

PostPosted: Sun Apr 18, 2021 7:47 pm    Post subject: Reply with quote

I had [and probably still have, somewhere?] a few sets of calipers for the Skoda Rapid [rear engine jobbie, not the VW lookalike!]...
For homologation reasons, Skoda fitted 4 piston calipers to the Rapid 136....[unlike on the Estelle which had a single piston caliper]

These 4 piston calipers were actually quite small, ie compact.
A lot more difficult to overhaul[free off?] than the Estelle jobbies.
However, the calipers were dismantlable [ as per the manuals]....they came apart and O rings etc had to be renewed, etc.

Plus, splitting the caliper really was the only way to deal with the pistons and bores.

As with nearly every component on the old rear engine Skoda's, they were designed to be taken apart, and put back together. The brake fittings especially were a delight, being proper threaded banjos, etc...on everything...so trip round the scrappy at teatime could yield a carrier bag full of banjos from just one car! [At the time, a banjo from a proper brake factor could be 3 or 4 quid, or more!!!]
_________________
Dellow Mk2, 1951 built, reg 1952.
Fiat 126 BIS
Cannon special [1996 registered. Built in 1950's]
----------------------------------------------
Ford Pop chassis, Ashley 1172 bodyshell, in pieces.
Back to top
View user's profile Send private message
Richard H



Joined: 03 Apr 2009
Posts: 2148
Location: Lincolnshire, UK

PostPosted: Wed Aug 04, 2021 7:20 pm    Post subject: Reply with quote

The square section o-ring ‘gallery seals’ can be difficult to find by application. They don’t generally come in the repair kits. However, most Girling calipers use one, most Lockheed another, etc. They can easily be ordered by quickly measuring the recess where the seal sits.
If going to the extent of replacing all the pistons and seals, I would always split them (once the pistons are out) as it makes it much easier to clean, and to check the galleries are clear from crud. I have seen totally blocked ones before, so exercise caution.
_________________
Richard Hughes
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Classic cars forum & vehicle restoration. Forum Index -> Mechanical Restoration All times are GMT + 1 Hour
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
OCC Merch link
Forum T&C


php BB powered © php BB Grp.