Adjust Car Front Wheel Bearings
1.Car Wheel Bearing Check play
You can tell when the front wheel bearings are loose or worn by checking the hub, with the wheel attached to it, for free play. Some people try to do this with the road wheel still resting on the ground,
but it is far better to make the check after the front of the car has been jacked up and supported with axle stands.With the wheel off the ground, grasp the top and bottom of the wheel and try to rock it back and forth (fig 1).
If you can feel the wheel rock, check that this play is in the hub assembly and not looseness in the suspension or steering. You can do this by replacing your hands on the wheel in the three o'clock nine o'clock position and rocking it again. If there seems to be the same amount of play as before, then the wear is probably in the wheel bearings, though there may also be wear in the track rod end or the ball joints.
A small amount of play is allowed in most wheel bearings about 1/16th of a inch at the most. Adjust the bearings first where possible, and then go on to find the rest of the wear.While the front wheels are off the ground, spin them by hand and listen for any noises which could be caused by a faulty bearing.
Very slight noise may be cured by packing the bearings with fresh grease. If the wheel does not spin freely, this may be because the brakes are holding it. On drum brake models the wheel can be freed by slackening off the adjuster on the brake backplate.
With disc brake models, slight contact between the pads and the disc is normal, so you may have to lever the pads away from the disc or even take them out to check 'the bearings Check the brakes afterwards if you have to do this ever.
If you find that the bearings are making excessive noise or seem to have far too much play, it is unlikely that adjustment or cleaning and greasing are going to offer anything more than a temporary cure.In these cases it is better to fit new bearings . Many other cars have non adjustable wheel bearings and you should not try to deal with the wear here by tightening up the hub nut. If you try this, it removes the running clearance and often causes the bearing to overheat and break down. If the bearings are worn you have to renew them.
2. Typrical Play & Wear Areas For A Car
Once you are sure that you have bearings which can be adjusted, begin by loosening the nuts or bolts holding the road wheel in place.
3.Alternative Locking nuts for car Bearings
Slacken them only a little so that they can be undone easily once the car has been raised from the ground.
Now jack up the front of the car and support it with axle stands so that the nuts or bolts can be removed completely and the wheel lifted away.
4. lever away the car wheel Grease cap
In the middle of the brake drum or disc you will see a domed metal cap. This holds the grease around the stub axle and prevents dirt and grit from getting inside the bearing assembly. Usually it can be removed by carefully levering it away with a large screwdriver or a pair of slip-joint pliers (fig 4).
On some models the cap is threaded in place and can only be removed by turning it with slip-joint pliers usually in a direction opposite to the rotation of the wheel that is, clockwise on the left hand wheel. A few cars notably the Volkswagen Beetle have the speedometer drive attached to the grease cap on one wheel and the clip which holds it in place has to be removed before the grease cap can be levered away.
Store the clip carefully. When you have taken off the cap, you should be able to see the large retaining nut together with its locking device. If this consists of a split pin and a castellated nut, first straighten out the split pin with a pair of pliers and then gently withdraw the pin from its hole. If the split pin has broken off inside the hole and you cannot grasp it with pliers, use a harnmer and a fine drift to tap the broken pin out. On some cars the hub is held in the axle by two large nuts with a locking plate between them. Bearing adjustment is made by turning the inner nut, but before you can move it the the locking tab which is hammered over the outer nut has to be straightened out using a hamrner and a small cold chisel. only then can you remove the outer nut and locking plate.
Another design, found on many Ford models, also uses two nuts which lock against one another However a split pin is used instead of a locking plate to secure the nuts.
5. Removing the car outer bearing from the hub
Once you have pulled out the split pin you will need two similar spanners so that the inner nut can be held stationary while the outer nut is loosened.
This done, the inner nut can be turned to make the adjustment. Whatever system you come across, once you have freed the adjustment nut, it can be turned inwards to take up the bearing free play ,but before you make the adjustment take off the thrust washer and the outer bearing so that you can inspect them they should just slide of the end of the stub axel.
Check that the bearing looks intact and is well coated with grease this should not be crumbly or Waxy If you find that the grease is not is good condition, you will have to dismantle the hub and bearing assembly so that you can clean the whole assembly and pack it with fresh grease . If the bearing appear to be well lubricated, slide it back in place together with the washer and carry on
with the adjustment.
This procedure varies from car to car. Many DIY mechanics simply turn the large nut until most of the play has been taken up, but the hub still spins freely. This approach is rather crude, but it can give fairly satisfactory results with some cars.
However, this should be regarded only as a temporary solution it is far more sensible to follow the manufacturer's recomendations. Check your manual for the procedure. You may have to tighten the centre nut to a certain torque figure and to turn the hub at the same time so that the bearinq beds evenly, and then slacken the nut by part of a turn.
4a. Remove car wheel bearing
However, a more common instruction is for the manafacture to give a end float figure,the end float figure is usually measured by sliding a feeler gauge,or the reccomended thickness between the bearing and the washer (fig 5) it should be a smooth sliding fit. If the feeler is a loose fit or is very tight,use a spanner to turn the nut slightly one way or the other to enable you to refit the split pin.
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