9*10 Braking system
10.6 Disconnect the relevant handbrake inner cable (arrowed) from the draw bar 6 Working inside ihe vehicle, remove Ihe screws and lift off the handbrake lever trim panel (refer to Section 9 for more detail). At the base of the handbrake lever, full/ slacken off the handbrake adjusting screw and locknut, to remove oil tension from the cable draw bar, then disconnect the relevant handbrake inner cable from the cable draw bar (see illustration) 7 Release the cable grommet from tho floor-pan, then withdraw the cable from the vehicle.
Refitting 8 Refitting Is a reversal of removal, bearing in mind the following points: a) Ensure that the cables are securely fastened In the clips on the floorpan beetshield and lower suspension a/m. b) On completion, check the handbrake adiustment, as described in Section 9.
11 Hydraulic system -bleeding
A
Warning: Hydraulic fluid is poisonous; wash off immediately and thoroughly In the case ot skin contact, and seek immediate medical advice if any fluid is swallowed, or gets into the eyes. Certain types of hydraulic fluid are Inflammable, and may ignite when allowed into contact with hot components. When servicing any hydraulic system, it Is safest to assume that the fluid IS inflammable, and to take precautions
11.17 Bleeding a rear brake line
against the risk of fire as though it is petrol that Is being handled. Hydraulic fluid is also an effective paint stripper, and will attack plastics; If any is spilt, It should be washed off immediately, using copious quantities of fresh water. Finally, it Is hygroscopic (it absorbs moisture from the air) • old fluid may be contaminated and unfit tor further use. Whan topping-up or renewing the fluid, always use the recommended type, and ensure that It comes from a freshly-opened sealed container.
General 1 The correct operation of any hydraulic system is only possible after removing all air from the components and circuit; and this Is achieved by bleeding the syslem. 2 During the bleeding procedure, add only clean, unused hydraulic fluid of the recommended type; never re-use fluid that has already been bled from the system. Ensure that sufficient fluid is available before starting work. 3 If there is any possibility of incorrect fluid being already in the system, the brake com-ponents and circuit must be Flushed completely with uncontamlnated, correct fluid, and new seals should be fitted throughout the system. 4 If hydraulic fluid has been lost from the system, or air has ontered because of a leak, ensure that the fault is cured before proceeding further. 5 Park Ihe vehicle on level ground, switch off the engine and select first or reverse gear (or P), then chock the wheels and release the handbrake. 6 Cheek that all pipes and hoses are secure, unions tight and bleed screws closed. Remove Ihe dust caps (whore applicable), and clean any dirt from around the bleed screws. 7 Unscrew the master cylinder reservoir cap, and top Ihe master cylinder reservoir up to the MAX level line; refit the cap loosely. Rememoer to maintain the fluid level at least above the MIN level line throughout the procedure, otherwise there is a risk of further air entering the syslem. 8 There are a number of one-man. do-It-yourself brake bleeding kits currently available from motor accessory shops. It is recommended that one of these kits is used whenever possible, as they greatly simplify the bleeding operation, and also reduce the risk of expelled air and fluid being drawn back into the system. If such a kit is not available, the basic (two-man) method must be used, which is described in detail below. 9 If a kit Is to be used, prepare the vehicle as described previously, and follow the kit manufacturer's instructions, as Ihe procedure may vary slightly according to the type being used; generally, they are as outlined below in the relevant sub-section. 10 Whichever method is used, the same sequence must be followed (paragraphs 11 and 12) to ensure Ihe removal of all air from the system.
Bleeding sequence 11 If Ihe system has been only
partial!?
disconnected, and suitable precautions wwe taken to minimise fluid loss, it should be necessary to bteod only that part of the system (le the primary or secondary circuit). 12 If the complete system Is to be bled, then It should be done working in the following sequence: a) Left-hand rear wheel b) Right-hand front wheel. c) Right-hand rear wheel. d) Left-hand front wheel. Note: When bleeding the rear brakes
on a
vehicle ritled with load proportioning valves: i the rear of the vehicle has been jacked
up to
allow access to ihe brake wheel cylinder,
tha
rear suspension must be compressed
(eg
raising the beam axle with a trolley
jack) so
that the load proportioning valves
remain open
throughout the bleeding process.
Bleeding -basic (two~man) method 13 Collect a clean glass jar, a suitable length of plastic or rubber tubing which Is a light fit over the bleed screw, end a ring spanner lo
Rt
the screw. The help of an assistant will also tie required. 14 Remove the dust cap from the first screw In the sequence if not already done. Fit a suitable spanner and tube to the screw, place the other end of Ihe tube In the jar. and
pour in
sufficient fluid to cover the end of the tube. 15 Ensure that the master cylinder reservoir fluid level is maintained at least above the
MIN
level line throughout the procedure. 16 Have the assistant fully depress the brefce pedal several times to build up pressure, then maintain it on the final downstroke. 17 While pedal pressure is maintained, unscrew ihe bleed screw (approximately one turn) and allow the compressed fluid and orto flow into the
Jar,
The assistant should maintah pedal pressure, following the pedal down to the floor if necessary, and should not rrtaase Ihe pedal until instructed to do so. When ihe flow stops, tighten the bleed screw again, have the assistant retease the pedal sfowty, and recheck the reservoir fluid level (see Illustration). 18 Repeat Ihe steps given in paragraphs 16 end 17 until the fluid emerging from the bled screw is free from air bubbles. If Ihe master cylinder has been drained and refilled,
and
at Is being bled from the first screw In the sequence, allow approximately five seconds between cycles for the master cylinder passages to refill. 19 When no more air bubbles appear, tighter, the bleed screw securely, remove Ihe tube arc spanner, and refit the dust cap (where applicable). Do not overtighten the bleed sew. 20 Repeat the procedure on tho remaining screws In the sequence, until ail air is removed from the system, and the brake pedal feels firm again.
Braking system 9®11
Bleeding • using a one-way valve kit 21 As their name implies, these kits consist ol a length of tubing with a one-way valve Fitted, to prevent expelled air and fluid being drawn back into the system; some kits include a translucent container, which can be positioned so that the air bubbles can be more easily seen flowing from the end of the tube. 22 The kit is connected to the bleed screw, which is then opened. The user returns to the driver's seat, depresses the brake pedal with a smooth, steady stroke, and stowty releases it; this is repeated until the expelled fluid is clear of air bubbles. 23 Note that these kits simplify work so much that It is easy lo forget the master cylinder reservoir fluid level; ensure that this Is maintained at least above the MIN level line at all times.
Bleeding -using a pressure-bleeding kit 24 These kits are usually operated by the reservoir of pressurised air contained in the spare tyre. However, note that it will probably be necessary to reduce the pressure lo a lower level than normal; refer to the instructions supplied with the kit. 2$ By connecting a pressurised, fluid-filled container to the master cylinder reservoir, bleeding can be carried out simply by opening each screw In turn (in the specified sequence), and allowing the fluid to flow out until no more air bubbles can be seen in the expelled fluid. 28 This method has the advantage that the large reservoir of fluid provides an additional safeguard against air being drawn into the system during bleeding. 27 Pressure-bleeding is particularly effective when bleeding 'difficult' systems, or when bleeding the complete system at the time of routine fluid renewal.
All methods 28 When bleeding is complete, and firm pedal feel is restored, wash off any split fluid, lighten the bleed screws securely, and refit their dust caps (where applicable). 29 Check the hydraulic fluid level in the master cylinder reservoir, and top-up if necessary. 30 Discard any hydraulic fluid thai has been Wed from the system; it will not be fit for re-use. 91 Check the feel of the brake pedal. If it feels at all spongy, air must still be present in Vie system, and further bleeding is required. Failure to bleed satisfactorily after a reasonable repetition of the bleeding procedure may be due to worn master cylinder seals.
12 Master cylinder- % removal
and
refitting SK
A
Warning: 8efore starting work, refer to the warning at the beginning of Section 11 concerning the dangers of hydraulic fluid.
Removal 1 Remove the master cylinder fluid reservoir cap, and syphon the hydraulic fluid from the reservoir. Note: Do not syphon the fluid by mouth, as It Is poisonous; use a syringe or an old poultry baster. Alternatively, open any convenient bleed screw In the system, and gently pump the brake pedal to expel (he fluid through a tube connected to the screw (see Section 11). Disconnect the wiring connector from the brake fiuld level sender unit. 2 Carefully prise the fiuld reservoir from the seals and release it from the top of the master cylinder. 3 Wipe clean Ihe area around the brake pipe unions on the side of the master cylinder, and place absorbent rags beneath the pipe unions to catch any surplus fluid. Make a note of the correct fitted positions of the unions, then unscrew the union nuts and carefully withdraw the pipes. Plug or tape over the pipe ends and master cylinder orifices, to minimise the loss of brake fluid, and to prevent the entry of dirt into the system. Wash off any spilt fluid immediately with cold wafer.
A 22.45 to 22.65 mm
Cut the finger tips from an old rubber glove end secure them over the open ends of the brake pipes with elastic bands • this wifi heip to minimise fluid lots and prevent the Ingress of contaminants.
4 Slacken and remove the nuts securing the master cylinder to the vacuum servo unit, then withdraw the unit from the engine compartment. 5 Where applicable, recover the seals from the rear of the master cylinder, and discard them; new items must be used on refitting. 8 With the master cylinder removed, check that the distance between the end of the vacuum servo unit pushrod and the master cylinder mating surface is as shown in the diagram. If necessary, the distance may be adjusted by turning the nut at the end of the servo unit pushrod (see illustration).
Refitting 7 Fit new rubber seals and then press the fluid reservoir into the ports at the top of the master cylinder 8 Remove all traces of dirt from the master cylinder and servo unit mating surfaces, and where applicable, fit a new seal between the master cylinder body and the servo. 9 Fit the master cylinder to the servo unit, ensuring that the servo unit pushrod enters the master cylinder bore centrally. Refit the
B Adjustment nut