Suspension

How to Cleaning and checking leaf springs

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Here you can get Cleaning and checking leaf springs.

Leaf springs are likely to wear because they have several moving parts. they should be inspected at intervals specified by the car manufacturer, or at major service intervals – usually every 12,000 miles (20,000 km). Before you jack the car up, put it on level ground , make sure that the tires are at their normal pressures which the car is at its normal ‘kerb weight’ without passengers, and with a full fuel tank.

Crouch down a touch distance behind the car and see how it sits on the road. It should appear level from side to side. If one side appears less than the other, there may be a weak or damaged spring thereon side. Prolonged use of the car with only the driver on board may cause a small sag within the springs thereon side of the vehicle. If the sag is critical, the springs may have to get replaced.

Move to every side of the car and examine the attitude of the swinging link spring shackles , which can be at the front or rear end of the springs. The links should generally be vertical when the vehicle is at its kerb weight. Any significant deflection to front or rear indicates a weakened spring. Compare the deflection of the shackles on each side of the car; they ought to be approximately the same. If, from this check, the rear spring or springs appear to be weak, make a further inspection to seek out the reason. it’s going to flow from to wreck , or to a general settling down of the springs through age.

Cleaning leaf springs

The standard leaf spring is made from several thin strips of sprung steel of different lengths and held together by clamps. It is subject to wear because the leaves rub against each other during suspension movement. to beat this, a tapered-profile single spring is fitted on some vehicles. Dirt particles between separate leaves accentuate wear and rust. The springs should be kept fairly clean so as to increase their useful life. The intervals at which this is often done are going to be given in your car handbook. Modern leaf springs don’t need lubricating with oil — which can damage any anti-friction material between leaves. Spray them instead with a silicone-based lubricant. With latest cars, leaf springs are found mainly within the rear suspension. Raise the top of the car to clean them.

Remove the hub caps and trims from the wheels, and loosen the wheel nuts. jack one side of the car in order that the wheel is obvious of the bottom , and support the car on an axle stand under a chassis member (not under the axle). Do an equivalent at the other side of the car, in order that it’s supported under the chassis on each side , with the wheels beyond the bottom. Chock the front wheels and take away both rear wheels.

The weight of the vehicle is now off the springs, which allows the leaves to separate slightly, making it easier to wash them. If the spring leaves are really caked with dirt and grease, cleaning them may be a messy job. The road or garage floor under the car are going to be badly stained unless you spread many newspaper or plastic sheeting to catch the drips. Use a proprietary decreasing fluid if necessary, either spraying it on or using an old scrub brush . Dry the springs afterwards with absorbent rags.

If the spring is just coated with dry dirt or rust, use a wire brush to get rid of all traces. Wear safety glasses or goggles to stop small particles of grit or rust being flicked into your eyes. Work the comb vigorously along the sides of the spring, the under and upper surfaces and around any clips which will be fitted to carry the leaves together. Afterwards, wipe it clean with a rag. After cleaning the springs, lubricate them lightly with silicone lubricant, replace both wheels and their wheel nuts. Lower the car to the bottom and fully tighten the wheel nuts. Replace the hub caps and trims, ensuring that they’re securely located.

Checking leaf springs and mountings

Carry out the checks while the springs are being cleaned (See Cleaning and checking leaf springs ). Look to ascertain if one spring is flatter than the other, in which case the car will probably have a pronounced tilt to at least one side. this may indicate that you simply should also check the ride height (See Cleaning and checking leaf springs ). Examine the sides of the spring leaves, search for cracks. Fractures found within the spring leaves can’t be repaired by welding. The leaf or the entire spring must get replaced as soon as possible by a garage. check out the lower surfaces of the leaves, where the ends of the shorter leaves bear against those above. the ideas of the shorter leaf may read the surface of the leaf above it, and make a small depression. The leaves then bind as they move against one another . a small depression is acceptable, but the spring should get replaced if Depression exceeds a in. (3 mm).

Check the condition of the shackle pins that undergo the rubber bushes. confirm that they’re not bent or badly corroded, during which case they’ll be very difficult to get rid of and will get replaced at a garage. Make sure the nuts on the U-bolts which hold the springs to the axle are tight. If they’re loose, the axle will move in reference to the springs. which will cause steering and tyre wear problems. it’ll also cause the brakes to judder on application. The spring centre-bolt head or the dowel that locates the spring on its mounting pad can also shear.

The axle is then liberal to move backwards, and should break free from the springs. A multi-leaf spring has two or more U-shaped clips towards the outer ends. They hold the most leaves in alignment with one another , and should be held in place by rivets or bolts. Check the condition and security of every clip. If you discover one loose or broken, have it replaced immediately. Otherwise the spring loading won’t be evenly distributed during the complete suspension travel over uneven ground. this might cause the master leaf to break under stress. In some cases, the lower, shorter leaves of the spring aren’t held in place by spring clips, but rely instead on the U-bolts to stay them in line with the remainder of the spring.

If the U-bolts become slack, the shorter leaves may move sideways. If they are doing , tap them back to place with a soft-faced hammer and tighten the U-bolt nuts fully. To check the rubber bushes within the eyes at each end of the springs, back the rear of the car abreast of ramps. Apply the handbrake firmly and chock the front wheels. Get under the car and wipe clean the areas round the bushes. Clean also the maximum amount of the bushes because the spring shackles allow. Inspect each bush for signs of wear and tear or distortion caused by the load of the vehicle on the suspension. See if the rubber has perished, cracked or been contaminated by oil. If the bushes are damaged, they need to get replaced at a garage, as replacement requires removal of the spring from the car and therefore the use of a press.

Checking for slackness and rust

Take the weight of the car off the suspension to see the springs for sideways movement. Remove the chocks from the front wheels and drive the car off the ramps. jack the rear and support all sides with an axle stand placed under a firm a part of the chassis, not under the axle. Grasp the spring and check out to twist it sideways at each end; it shouldn’t move. Check further by trying to lever the bushes from side to side. If the rubber bush is in good condition, there should be no sideways movement of the spring. If there’s, have the bush replaced.

Use a wire brush to wash the grime from round the spring mountings within the floor pan of the car and therefore the shackle bolts. Check each shackle bolt and nut for tightness, and tighten any that are slack. Take the chance to seem for signs of corrosion on the ground pan and chassis member round the mountings. Probe suspect areas with a screwdriver or tap them with a hammer.

The metal should be completely sound. If you discover the floor pan or mounting areas to be rusting badly, take the car to a garage for repair. don’t use it for the other journey until this weakness has been fixed. If there’s only surface rust, use a wire brush to clean the metal. Treat the affected area with a proprietary rust preventative, followed by an underbody sealant.

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