22 December 1995

PERFORMING A SEAL CHANGE

USUALLY, the first sign of a crisis on the hub seal front is an oily brake backplate or disc, coupled maybe with the brakes pulling to one side. Like many mechanical jobs its best attended to quickly – not only are bad brakes anti-social, but the bill balloons if a leaky seal ruins shoes or pads.

Here we detail rear seal replacement on a Series 111 Land Rover; procedure differs only in detail for later 90/110s and Range Rovers. Free-wheeling hubs may marginally complicate things at the front.

The job can be done in around an hour with an ordinary tool kit, but bearing locknuts will thank you for investing about £14 in a 2 1/16in AF box spanner. This is much kinder and safer than a chisel or stilsons, and the only tool able to tighten the nuts properly.

Useful tip before you start: A blocked axle breather can be at the root of hub leaks – its the small hat-shaped item on top of the nearside axle casing. Unscrew and clean with solvent and compressed air.

(2) With a drip tray at the ready to catch oil, take off the hubcap, halfshaft nut and ring of bolts holding the driving flange (left). Alternatively leave the nut in place and withdraw the shaft complete with flange. Clean both flange faces.

(10) Slip on the tab washer and outer locknut, then box spanner it tight. Bend down one tab on each nut.

(1) Sign of trouble – an oily backplate suggests seal problems. Start replacement by putting the rear axle of the vehicle on stands and taking off the wheel – we used a ramp – and back off the brake adjuster; its the single hex-head bolt at 11 oclock on the backplate.

(6) Prise out the old hub seal. Lift out the bearing inner race and check rollers and track for damage. Pop it back, then gently seat the new seal flush with the hub using a soft-faced hammer. Run a little fresh oil around the seal lip to lubricate it.

Occasional oil seal failures are part of Land Rover ownership. Paul Edwards of Hants-based independent 4×4 specialist Kingsley Cross Country turns Andrew Pearce into a quick change artist

(5) The hub seal runs on the inner, largest stub axle diameter. Damage or roughness here interferes with proper sealing, so unless you fancy more leaks either find a good second-hand stub axle or go out and buy a new one.

(9) Adjust the bearings by tightening the locknut clockwise by hand, rotating the hub as resistance builds. Then back it off about 1/8 turn in the direction arrowed.

(3) Undo the drum securing screws

(they might need an impact driver) and use a 3/8in UNC bolt to push off the brake drum. DO NOT clout the drums back edge with a hammer,

as its brittle and likely to crack.

(4) Knock back the locknut tabwasher and use a box spanner to undo the outer nut. Pull off the tabwasher, undo the inner nut and slide off the thrust washer. Withdraw the hub from its stub axle, using your thumbs to hold in the outer bearing race. Wrap the outer race in clean cloth and set it to one side.

(7) Brake parts will be more or less oily. Wash the drum in solvent (caution – wear gloves and eye protection) and degrease the backplate. Clean the brake shoes in situ or replace the axle set if friction material is contaminated beyond recovery. Renewing the set keeps braking balanced.

(11) Right: Refit the halfshaft, pushing down and turning so it slips home inside the differential. Add the flange, using a new paper gasket and sealing it with a little Hylomar or similar. Re-use or replace the felt/rubber halfshaft seal. Fit flange bolts and halfshaft nut for final tightening later. Slide on the brake drum, tap its sides to centre the shoes and replace holding screws. Adjust the brake so shoes rub very lightly, refit wheel and lower the car back to earth. Torque flange bolts to 30-38lb ft, the halfshaft nut to 10-15lb ft, lining it up with split pin holes and locking it with a new pin. Replace the hub cap, tighten the wheel nuts to 75-85lb ft and check axle oil level.

(8) Slide the hub back gently over the stub axle and settle the seal on its register. Refit the outer bearing race, thrust washer and first locknut.