Repair 7

Driving any automobile is nothing, if not an exercise in constant blind faith. Just the fact that any soccer mom in the world can take a 50 mph curve without wondering what would happen if a tire blew, a ball joint broke or an axle-shaft snapped is testament to the pragmatic advantages of deliberate ignorance. Still, it never hurts to be prepared for any eventuality, especially if you find yourself in circumstances where breakage is likely.

Open Differential, Accelerating in a Straight Line

Most cars use "open" differentials, which route power to the wheel with the least traction. If you break an axle-shaft or constant velocity joint in a front-wheel drive car with an open differential while accelerating in a straight line, then power will simply flow into the broken axle and spin it. The engine will rev and the axle will spin, but the car wont move. The same goes for front axle-shafts in a 4WD truck, but if the axle tube itself breaks, then odds are that your truck will nose-dive into the road.

Locked Differential, Accelerating in a Straight Line

Many performance cars use locked, limited-slip or "torque biasing" differentials. Locked axles are just that; the left and right wheels always turn at the same speed. Limited-slip differentials can transfer some or all of the power to the wheel with the most traction -- the one spinning slower -- and torque-biasing differentials can transfer some, but not all of the power. With any of these differentials, the car will suddenly veer in the direction of the broken axle since the other wheel is the one doing all the pushing.

Open Differential, Accelerating Out of a Curve

If the axle-shaft is on the inside of a curve -- the right side for a right-hander, left for a left-hander -- while accelerating out of a curve, the vehicle will most likely dart inward toward the curve. Front-wheel drive cars and trucks in 4WD naturally exhibit a certain amount of understeer as the front tires struggle to both accelerate the car and keep it turning. Should the axle-shaft break on a front-wheel drive car, itll quickly-turn into a no-wheel-drive and probably exhibit neutral handling. A 4WD truck or all-wheel drive car will suddenly turn into a rear-driver, which can result in snap oversteer and a probable spinout if the driver doesnt lift off the gas soon enough.

LS or TB Differential, Accelerating Out of a Curve

Front-wheel drives with a limited-slip or torque biasing differential will exhibit a somewhat more severe oversteer condition as power flows from the inside tire to the outside. A clutch-type limited slip may induce a severe oversteer condition and possible spinout, if its powerful enough to transfer all of the engines power to one wheel. The same goes for all-wheel cars and 4WD trucks with an LS or TB differential, but far more so.

Locked Differential, Accelerating Out of a Curve

Fully locked front differentials will act a bit differently than those that allow the wheels to spin at different speeds. This is especially true off-road, which is the only place youre likely to see anything with a locked front differential. Cars have differentials because the outside tire has to turn faster than the inside tire; if you lock the differential, the inside tire will always spin while turning and contribute little to no traction. Under these circumstances, the truck may break either the inside or outside axle, depending on the conditions.

If the inside axle breaks, all the power will go to the outside tire, inducing an understeer condition. If the outside axle breaks, that tire will gain traction while the inside tire continues to spin, inducing a neutral to understeer condition. One caveat though, a locked differential may do exactly the opposite, particularly if the truck lacks the power to spin the outside tire while turning, or spin the inside tire during a tight turn.

Wheel alignment affects the steering pattern of your vehicle and is a major contributor to tire wear. Improperly aligned tires may pull to the left or right when driving, which is a dangerous safety hazard. The three elements of alignment to consider are caster, camber and toe. These terms er to the placement of the wheels, whether they be set forward or backward, tilted in or out or pointed to the inside or outside.

Laser Wheel Alignment Tool

Laser wheel alignment tools make taking toe measurements quick and easy. Wheels with a toe-in setting face inside, while toe-out wheels point to the outside when the tires are viewed head on. Laser tools replace the old method of measuring, which usually involved painting a line around the tire and measuring by hand. With a wheel alignment tool, youll only need a steel bar and bungee cord to set the toe on a vehicle with an "in" or "out" toe setting. While these tools make setting the toe easy, the can be expensive and may not be practical for home workshops.

Caster/Camber Gauges

Caster and camber are wheel alignment elements that can be measured with caster/camber gauges. Caster ers to the position of the wheels top and bottom ball joints in relation to the spinning axis, the cars axle. When viewed from the side, the ball joints may be positioned either in front of or behind the axle, rather than sharing an equal distribution for proper alignment. Camber can be viewed by looking at the tires head on; the top of the tire may be tilted in or out, which can cause uneven wear on your tires. Caster/camber gauges are attached to wheel hubs and use a level to determine the amount of positive or negative caster or camber associated with each wheel. You turn the wheel to one direction, take a reading, then turn in the other direction, take another reading and calculate the difference. Manual gauges are one option, but digital gauges take the guesswork out of caster and camber measurements.

Camber Kits

Most vehicles are built with the ability to adjust toe and caster in the suspension set-ups, but, according to Sport Compact Only, "less than half of vehicles manufactured have camber adjustability." Those vehicles that do have this ability, usually only allow for a small range of correction. Camber kits widen the range of camber adjustability so you can correct excessive camber problems beyond factory specifications. They are almost always necessary if you lower your vehicle, which can produce excess negative camber. The shim and washer camber kit design is fairly easy to install; it fits snugly against the hub and acts like a shim to hold the tire out. Some camber kits are more difficult to install, however, and may require the complete removal or replacement of your vehicles ball joints.

The front spindle nut on a 1995 Honda Accord is a single-use nut. This nut contains an outer flange that must be staked into a groove on the end of the axle shaft. The staking procedure prevents the nut from loosening when the vehicle is driven, but necessitates the replacement of the nut when its removed. In order to remove the 36 mm axle nut, the staked portion of the nut must be pounded out of the axle shaft to allow the nut to spin freely.

Instructions

Removal

1

Break the front lug nuts loose with a lug nut socket and a t-handle breaker bar.

2

Lift the front of the vehicle with a jack and set it down on jack stands

3

Remove the lug nuts and wheel. Locate the axle nut in the center of the rotor, on the end of the axle shaft. Align a steel punch with the staked-in portion of the axle nut, then use a hammer to drive the punch into the staked-in portion to undo the staking.

4

Place a 36 mm socket on the end of a t-handle breaker bar and place the socket over the axle nut. Ask an assistant to hold a large pry in-between the wheel studs; this holds the hub still so the axle and transmission arent damaged.

5

Loosen and remove the axle nut, then discard it.

Installation

6

Install a new axle nut onto the axle shaft, and have an assistant hold the pry bar between the wheel studs again.

7

Tighten the nut and torque it to 181 foot-pounds with a torque wrench.

8

Align a steel punch with the channel on the axle shaft, then strike the punch with a hammer to stake the new nut into place.

9

Reinstall the wheel and lug nuts, then lower the vehicle back to the ground. Torque the lug nuts to 80 foot-pounds with a torque wrench.

Nissan introduced the first-ever compact pickup truck to the U.S. market in 1958, back when Nissans were still known as Datsuns. Nissan redesigned its pickup truck several times, giving it a complete makeover in 1986. While several trims of the vehicle were available, Nissan generally erred to its compact pickup simply as the Nissan Pickup until they discontinued production of it in 1997. The mid-sized Frontier replaced the Pickup in 1998, and Nissan introduced the full-size Titan pickup truck in 2004.

General Alignment Information

The Nissan offered its 1995 Pickup in a variety of two-wheel-drive and four-wheel-drive trims, but all two-wheel-drive trims had the same alignment specs, as did all four-wheel-drive trims. The caster, camber, toe and steering axis inclination (SAI) are all adjustable on the front end of all trims of the 1995 Nissan pickup. The caster is the angle of a vehicles steering pivot, as it is viewed from the side of the vehicle. The camber is the angle that the wheel tilts when viewed from the front of the vehicle. If it tilts out at the top, the camber is positive. If it tilts in at the top, it is negative. The toe is the measurement of a wheels angle in relation to the center line of the vehicle. On most vehicles, the front wheels are intended to point slightly toward each other. The SAI is the measurement of the angle of the steering pivot when viewed from the front of the vehicle. All measurements are given in degrees.

Alignment Specs for the 1995 2WD Pickup

The caster angle on the front end of the 1995 two-wheel-drive Nissan Pickup should fall between +0.37 degree and +0.5 degree, with a cross tolerance of +0.75 degree. The camber angle should fall between +0.42 degree and +0.50 degree, with a cross tolerance of +0.75 degree. The toe-in should be between +0.8 degree and +0.25 degree. The SAI can range from +0.5 degree to +9.1 degrees. The alignment was not adjustable on the rear end of two-wheel-drive trims of the 1995 Nissan Pickup because it came with a fixed rear axle.

Alignment Specs for the 1995 4WD Nissan Pickup

The caster angle on the front end of the 1995 four-wheel-drive Nissan Pickup should fall between +0.50 degree and +1.3 degrees, with a cross tolerance of +0.75 degree. The camber angle should fall between +0.50 degree and +0.67 degree, with a cross tolerance of +0.75 degree. The toe-in should be between +0.8 degree and +0.32 degree. The SAI can range from +0.5 degree to +8.1 degrees. As with the two-wheel-drive trims, the four-wheel-drive trims of the 1995 Nissan Pickup truck came with a fixed rear axle and the alignment was not adjustable on the rear end.

Wheel alignment adjusts the wheel angles so that they are parallel to one another and to the ground. Proper wheel alignment and related maintenance is critical to keeping a vehicle in top condition. Wheel alignment is also important for safety reasons--poor alignment can result in issues regarding uneven tire wear and tracking, as well as create steering problems.

How Wheel Alignments Are Performed

Wheel alignment technicians check an automobiles alignment by test driving it prior to servicing it. Test drives provide the technician firsthand knowledge of steering and tire performance, giving him important information that will allow him to effectively diagnose any issues.

Front-Wheel Alignment

Front wheel alignment service inspects and adjusts the alignment of the vehicles front tires and axles. A car that regularly pulls to one side or has uneven tire wear indicates the need of a front-wheel alignment, especially when confirmed by a technician. As of 2010, front-end alignment can run approximately $30 to $70, depending on the company and location.

Four-Wheel Alignment

Four-wheel alignment inspects all tires, but technicians may perform it in two different ways. A wheel technician can inspect all four wheels but only service the two front wheels, or he can inspect and service all four wheels, which is known as a full four-wheel alignment. Full alignment services are more expensive than other types of alignment services because of the extensive work. As of 2010, this service can cost between $50 to $100 depending on the company and its location.

Since the introduction of the Onboard Diagnostics II (OBD II) system in 1995, two oxygen sensors -- front and rear -- monitor engine performance and emissions in all American-sold vehicles. These small, but vitally important components communicate with the engine control unit to maximize performance and minimize emissions, and should be replaced or fixed immediately if found to be malfunctioning.

Front Oxygen Sensor Function

The front -- or upstream -- oxygen sensor, so named for its position in front or upstream of the catalytic converter in the exhaust manifold, measures the amount of unburned oxygen present in the exhaust that exits the engines combustion chamber by producing and reporting a voltage level to the ECM. This indicates the air to fuel ratio that the engine is receiving and whether or not the ECM needs to alter that mixture in order to reach the proper 14.7:1 ratio.

Rear Oxygen Sensor Function

The rear oxygen sensor is located downstream of the catalytic converter, and has a more basic function: it monitors the effectiveness of the catalytic converter. Tasked with removing many of the harmful toxins from engine exhaust, the catalytic converter is an important part of the exhaust process. The ECU compares data compiled from the rear oxygen sensor with that of the front oxygen sensor to ensure that the catalytic converter is doing its job. A non-functioning rear oxygen sensor wont affect performance, but it will likely trip a dashboard indicator.

Design

Although they have different purposes, front and rear oxygen sensors employ the same basic design to measure oxygen levels. Resembling spark plugs, these small devices produce a voltage between 0.2 and 0.9 volts, based on the amount of oxygen flowing past their bulb, and relay that information to the ECU. Most modern day oxygen sensors are electrically heated on start-up until they can maintain their own 600-degree operating temperature.

The chrome bonnet scoops on the Mini Cooper S and JCW models have been known to melt due to the high heat of the engine. Mini has developed a fix for the problem, which is covered by the Mini Cooper warranty.

Models Affected

The Cooper S and JCW models from model years 2006 until 2010 with the chrome bonnet scoop are affected. The Cooper S and JCW hardtop, convertible and clubman can all develop the problem.

Causes

For the 2006 model year Mini went from a superchared to a turbocharged 1.6 liter engine. Initially the 2006 hood scoops were non-functional and closed off; however, new engine design meant more heat was generated at the top of the engine under the hood scoop, causing it to overheat and warp.

Solution 1

Mini dealers can replace the scoop under warranty with a new design that will not warp as easily.

Solution 2

Remove the scoop and put holes through the scoop to allow it to vent. Recent Mini hood scoops have a few holes in them, and increasing the number of holes may prevent the scoop from warping.

The front brakes on your 1986 Chevy Celebrity operate by pressing pads against a rotor to slow or stop the car. The pads are held in place by the brake caliper that compresses against the rotor. The wheels are mounted to the rotors, which complete the braking assembly. When brake pads squeak, its time for replacement. Replacing the front brakes on your Chevy Celebrity requires caution since the repair is done under the car. Youll also need an assistant.

Instructions

1

Prepare the car for repair by parking it on a dry level surface. Put the car in park, turn off the engine but do not set the parking brake. Prevent the car from accidentally rolling during the repair by bracing the rear wheels using wheel chocks or bricks.

2

Lift the hood and locate the master brake cylinder reservoir. The reservoir is located on the upper-right side, mounted onto the firewall when facing the car. Remove the reservoir fill cap to release the pressure in the brake line.

3

Take out half the fluid in the reservoir using the turkey baster and discard. This will allow room for the caliper piston to retract as necessary during the pad installation.

4

Slide the floor jack under the front axle and lift the car to loosen the wheel lugs. The wheels should remain touching the ground to prevent them from turning. Loosen the lug nuts on both front wheels, and then raise the car higher to put the jack stands in place.

5

Place the jack stands directly under the axle and then lower the car down onto the stands. Be sure that the car remains off the ground for the wheels to be removed.

6

Remove the wheel lug nuts on the left side first and take off the wheel. Complete the entire brake pad replacement repair on this side before starting the opposite side replacement.

7

Locate and remove the two mounting bolts located on either end of the caliper using the socket wrench.

8

Lift off the entire caliper assembly and pads from the rotor. Remove and discard both worn brake pads. Allow the caliper assembly to rest on bricks or another suitable structure to prevent the caliper from simply hanging by the brake fluid hose line.

9

Push the caliper piston back into the caliper bore to create enough space for the replacement brake pads using the C-clamp tool. The new replacement pads are thicker than the worn pads, so the piston must be completely retracted into the caliper bore for them to fit.

10

Install both the replacement brake pads, being certain that they are seated correctly. Place the caliper assembly back onto the rotor and mounting bracket. Install and tighten the two mounting bolts using the socket wrench.

11

Repeat Steps 7 through 10 on the other brake assembly.

12

Refill the master brake cylinder reservoir with new DOT 3 rated brake fluid. Have an assistant press the brake pedal. Replace the reservoir cap and then release the brake.

13

Remove the cap and again have the assistant press the brake pedal. Replace the cap again and then release the brake to remove any trapped air within the brake line.

14

Mount the wheels and install the lug nuts on both sides using a crossing-pattern. Raise the car and remove both jack stands. Lower the car down to where the wheels are just touching the ground. Securely tighten all the lug nuts on both sides, again using a crossing-pattern.

15

Lower the car to the ground. Remove the jack and wheel braces. Drive the vehicle while making several sudden and abrupt stops to test the brakes. Recheck the brake fluid reservoir and add fluid as needed.

Removing a seat from your 1983 Mercedes 300D may be necessary if the seat is torn or otherwise damaged. Recovering or replacing the seat with a new one can bring the interior back to a like-new condition. A new seat for a 1983 is not going to be easy to find, but aftermarket option do exists and used seats are available from some salvage yards. For cosmetic fixes, the seats can be covered or reupholstered if a replacement cannot be found.

Instructions

1

Open the door of the car all the way to allow access to the seat. Slide the seat all the way to the front position. Locate the mounting brackets and adjuster slides under the seat.

2

Locate the two rear retaining bolts that run through the mounting brackets and into the floor. Remove both bolts with a socket and ratchet, setting the bolts aside in a safe place.

3

Slide the seat all the way to the rear position on the seat track. Locate the retaining bolts on the front of the seat, where the brackets meet the floor. Remove the two front bolts from the floor and brackets with a socket and ratchet, setting them aside for reuse later.

4

Lift the front of the seat, tilting it back so you can access the underside. Locate the electrical connector on the underside of the seat and depress the locking tab to release it. Separate the wiring harness on the seat from the harness on the car.

5

Lift the seat and remove it from the car through the door opening. Set it aside in a dry spot to avoid any damage while it is out of the car.