Renewing MacPherson-strut inserts

Here you can get Renewing MacPherson-strut inserts, Removing a standard strut, a unit-replacement strut and Removing and refitting a damper.

When the damper inside a MacPherson strut wears out, you’ll buy a replacement cartridge which — depending on type — may or may not include new parts for the strut itself. You will need a pair of coil-spring compressors . Hire them if necessary, don’t use makeshift arrangements of clamps, wire or cord. they’re unsafe.

Loosen the wheel nuts and raise the car on axle stands under chassis or frame members. Remove the wheels, and open the bonnet or boot lid to realize access to the suspension from above and below.

Removing a standard strut

Unscrew the three nuts above the mounting to release the top of the strut. don’t loosen the central nut between them, which would release the coil spring from the strut. Remove the two bolts underneath the track control arm , which fix the strut to the arm. At this stage, examine the suspension before proceeding further: on several cars there’s no need to disconnect any of the steering ball joints or the anti-roll bar (if fitted).

On others the track-rod end, and sometimes the track control arm or anti-roll bar or both, must be detached. Clamp the flexible brake hose to close it. Use a brake-hose clamp. Disconnect the hose from the rigid brake pipe on the strut by unfastening the union nut. Lift the strut and therefore the brake assembly from the track control arm. take care – they’re heavy. you’ll need a helper. When reassembling, bleed the brakes and top up the master cylinder if necessary.

Removing a unit-replacement strut

Unscrew the two nuts (on some cars three) above the top mounting turret to release the top of the strut. Do not unscrew the central nut between them, which would release the coil spring. The top a part of the strut is fixed to the bottom part by bolts – there could also be one, two or sometimes three.

The lower, or lowest bolt may be eccentric, as a means of adjusting the camber. Mark its head so that you’ll refit it in just the same position. Remove the nuts and pull out the bolts to free the top half of the strut.

Removing and refitting a damper

Clamp the strut during a vice with the upper end higher than the lower end to prevent the oil running out. Fit a pair of spring compressors round at least four coils of the spring, and tighten evenly until the spring is well compressed and tension on the upper spring mount is released. Then unscrew the central nut at the top of the damper; on a unit-replacement strut it must be unscrewed with an Allen key. Lift off the top spring pan and any spacers, and the upper bearing if applicable. Then take off the compressed spring. If there’s a rubber gaiter round the damper, remove this too.

Free the damper from the strut by unfastening the massive gland nut between its two telescopic sections. If you are doing not have a spanner that matches the nut, put it within the vice and switch the strut. If the nut is rusty, penetrating oil will help to free it. Check the threads on the strut tube for damage, and clean them.

You may now be ready to remove the damper as one , sealed unit. If so, clean the within of the strut with petrol, let it dry and put within the new damper cartridge. Alternatively, you’ll need to dismantle the old damper to remove it, but it’s not difficult to suit the replacement cartridge, because it’s in one piece and includes a replacement piston arm.

Read the instructions on the cartridge box. they may tell you to pour oil into the strut casing – usually 2fl. oz (50ml) of light engine oil or special damper oil – to chill the cartridge and prevent corrosion. Refit the gland nut. Fix it firmly by denting the outside of the casing in one spot with a hammer and punch. Refit the spring. make sure it’s set straight, then decompress it evenly. Fit the top spring platform, nut and packing pieces. Then tighten the centre nut fully.

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