Replacing crankshaft front oil seals

Replacing a crankshaft front oil seal
The side cover may be held by one or more bolts. Undo them, then prise it off carefully.
The side cover may be held by one or more bolts. Undo them, then prise it off carefully.
On most cars you need to remove several parts to get at the seal.
Slacken the alternator or dynamo adjuster and pivot bolts, push the unit inwards and ease off the drive belt. Remove the belt completely.
Remove the radiator (See How to remove a car radiator) if necessary, to make room for removing the crankshaft pulley.
Mark the position of the rotor arm on the distributor body. Unbolt the distributor; this type has a flat base and a flange-and-stub fitting A flat-based distributor has a paper gasket. Types with a clamp plate have a ‘O’ rubber ring.
Mark the position of the rotor arm on the distributor body.Replacing crankshaft front oil seals
Unbolt the distributor; this type has a flat base and a flange-and-stub fitting
A flat-based distributor has a paper gasket. Types with a clamp plate have a ‘O’ rubber ring.
If the car has a manual gearbox, select first or reverse gear and put the handbrake full on. rubber sealing.Otherwise, disconnect the battery and remove the starter motor.
Insert a tyre lever or large screwdriver into the starter aperture so that it jams in the teeth of the ring gear on the flywheel.Replacing crankshaft front oil seals
Unscrew the pulley bolt anticlockwise with a socket and bar. Start it turning with a sharp blow on the bar.
Remove the key that locks the pulley with the crankshaft. Prise out the old seal with a screwdriver. Take care not to score the housing. Jam the flywheel ring gear to prevent the engine turning while you undo the crankshaft pulley bolt. You may need a universal puller to remove the pulley. Tap in the new seal with a wooden block, keeping it absolutely straight.
Remove the key that locks the pulley with the crankshaft.Replacing crankshaft front oil seals
Prise out the old seal with a screwdriver. Take care not to score the housing.
Jam the flywheel ring gear to prevent the engine turning while you undo the crankshaft pulley bolt.
You may need a universal puller to remove the pulley.
Tap in the new seal with a wooden block, keeping it absolutely straight.ring seal.
On engines that rotate anticlockwise (viewed from the front) the pulley bolt unscrews clockwise.
The pulley may slide off easily; if not, use a universal puller, which you may be able to hire.
The pulley is kept from turning on the crankshaft by a key fitting into grooves on the crankshaft and pulley.
Remove the key and keep it safe until ready to refit the pulley.Replacing crankshaft front oil seals.
Thoroughly clean the area around the oil seal and check how it is fitted. If you cannot see the outer end of the seal, remove the timing-belt cover or chain cover (not the belt or chain) and possibly the water pump (See Replacing a water pump) to reveal it. On an engine with a belt-driven overhead camshaft, remove the belt and its drive sprocket.
Lever the seal out with a screwdriver, working carefully to avoid scoring the seal housing.
Clean all dirt and oil from the housing, and set the new seal in place with its open (spring) side towards the engine.
Put a wooden block or a piece of large tube against the seal and gently tap it squarely into the housing until it is fully home. Refit the timing cover, if removed.
Thoroughly clean the sleeve at the back of the pulley, and look for any roughness on it where it touches the seal. If necessary, smooth it with fine wet-and-dry abrasive paper.car seal.
Smear clean engine oil on the pulley sleeve and seal, then refit the pulley with the key and keyway aligned. Tighten the bolt to the correct torque (consult a service manual or a dealer if in doubt).
Refit all the components in the reverse order of dismantling.Replacing crankshaft front oil seals.