Getting Through the MOT

I recently took my bug for its annual MOT as oppose to my brother who usually does the honours on my behalf. And unfortunately, I had to drive my car away with a fail certificate (the current MOT had yet to expire!), what a feeling. The car failed due to a couple of basic stuff like the brakes, but mainly due to the fact that there was too much play in the front wheels in the suspension arms>.. And on trying to source some information, I came across the following MOT pre-check list that I thought was quite good! It is aimed at Classic Cars in general as oppose to air-cooled VW dubs. Hope you find it useful!

Angela Antoniou.

PS Big thanks to my Bro.

Everything you need to know

Simple pre-MOT checks can save you time and money each year, about one-third of cars over three years old fail their annual MOT test first time round. Many failures are caused by minor defects that owners could have spotted and put right before putting their cars up for the MOT test. Follow the steps below and you could save a wasted test fee, repair costs, and delay in getting your car through the MOT. These simple home checks don't need special equipment and should take about an hour.

Windscreen & Wipers

On the road, the driver should be aware if the vehicle has a tendency to stray to one side on level surfaces, or if it pulls one way when braking.

The former indicates suspension or steering misalignment, while the latter is a brake problem. This should show up on the MOT station's brake tester, but if it is caused by leak in the brake hydraulic system it will need urgent attention before the MOT test. Chassis or steering problems unless indicated by uneven tyre wear - will probably escape notice unless there are obvious signs of chassis or steering damage or poorly executed repair work. The only way to check for correct chassis alignment after accident damage has been repaired is for the car to be put on a chassis jig. Other problems to watch for on a test drive are worn drive-shaft joints, indicated by a knocking from the front when pulling away on full steering lock making a tight three-point turn will usually reveal this fault. If there is any knocking from the wheel area when driving in a straight line, the universal joint is close to total failure, with expensive consequences. Heavy rumbling indicates worn wheel bearings.

Mirrors

Mirrors are a common fail point. There must be a right-hand door mirror and one other, either inside or on the other door; many cars have all three. A cracked mirror may pass an MOT inspection - it depends whether it still provides a clear view. If the glass is still there such a fault is easily remedied by fitting a stick-on replacement. If the mirror is missing or damaged beyond repair, an original manufacturer's replacement will be needed - it has to fit the housing exactly. Alternatively, scrap yards often stock mirrors and mirror housings.

Body & Doors

A rust hole in a door, wing or wheel-arch is permitted as long as it does not affect the structural strength of the body. However, there must be no protruding, sharp or jagged edges. If the bumper is bent or twisted, with protruding edges, it's best to replace it or remove it altogether, including the mounting brackets. Where the 'bumper' is a plastic moulding forming part of the outer bodywork, professional repair or replacement is the only answer. Doors must close securely and operate from both inside and outside. If there is a snapped-off handle or broken linkage on a rear door that is never used anyway, it's still a fail point.

Seats & Belts

Pull each seat belt out to its full extent and check there are no cuts or frayed areas. Fasten each belt, examine the buckles, and inspect where the belt anchors are mounted onto the car body. The seats must be secure firmly mounted to the floor with no corrosion around the mounting points. All clips, latches and seat adjustment mechanisms must work properly.

Under the bonnet

Check the battery, which must be securely fixed. A radiator leak won't mean a fail, but leaky or damaged fuel pipes will. Both flexible and metal fuel lines from carburettor or injection system back to the fuel tank will be checked for secure mounting and lack of corrosion. While it is only possible to look at what is readily visible, check anyway. The flexible pipe inside the engine compartment may be in a poor state. Other pipes to check are the brake lines running from the brake master cylinder, usually mounted high up on the bulkhead behind the engine along with the servo unit. Inspect these for signs of corrosion or fluid leakage, and give them a very gentle tug to check for secure mounting. Inspect the inner wings and other areas visible in the engine bay. Any rust here may result in a fail, if it's within 25cm (10 inches) of a load-bearing part of the structure. Strictly speaking, a rust hole in the middle of the car's floor-pan may still pass - though it would be unwise to leave it un-repaired.

Number plates

Stand back and look at both of the number plates. These are a part of the MOT test, too, and must be clean, undamaged (with not even a crack) and securely fixed. The number plate light must also work.

Steering, suspension & Driveshaft

Examine any power steering pipes for signs of oil leakage. If the ends of the steering rack are fitted with rubber bellows or gaiters, look for oil or grease leaks here. A split means a replacement part - best fitted by an expert. On front-wheel drive cars, the same applies to the rubber 'boots' on one or both ends of the drive-shafts running between the gearbox and front wheels.

Signs of oil or grease mean a replacement boot is required. If the shaft has lost all its grease the universal joint inside may be so worn that a new shaft has to be fitted - an expensive job Little can be seen of the steering and suspension systems without jacking the car up and removing the wheels, so many owners will probably skip these checks. Remember that it is essential to have a good jack (not the one supplied with the car, which is only intended for emergency wheel-changes) and solid ramps or stands. Obey the rules of loosening the wheel nuts, jacking up, lowering onto stands, finally removing the wheels and positioning each one beneath the car as an additional precaution.

The first check is wheel bearings and suspension joints. Jack up without loosening the wheel nuts. Grip the tyre top and bottom and try to rock. Anything more than the merest movement indicates a loose bearing. These may or may not be adjustable to take up slight wear. Grip the sides of the tyre and rock it from side to side, then heave the wheel from one side to the other on the steering (have the ignition key in place, or remove the key when on the 'garage' position, otherwise the steering lock will activate). Remove the wheels. The car may have to be lowered to the ground unless another person can press the foot brake while the wheel nuts are undone. Use the handbrake to lock the rear wheels. Examine the rubber boots on all the suspension and steering joints. If there are any splits, or if the rubber is perished, a new unit will be needed even if at that moment the joint is still mechanically sound. With the wheels off, the dampers (shock absorbers) are visible. These are tubes filled with oil and a piston which inhibit the natural 'bounce' of the suspension springs. Not only do dampers wear inside, letting the piston move more easily through the oil, they eventually leak oil. The result is a bouncy and unstable car, particularly when cornering and braking. The rubber bushes at either end of the shock absorber tend to fall apart and have to be replaced. Look for oil leaks where the shiny piston rod comes out of one end of the damper. If oil is visible, it's a fail point.

With the wheel back on and the car sitting on the ground, test that the shock absorbers actually work. Push down hard on each corner of the car in turn, then release. If the car springs back and keeps on bouncing, you'll have to budget for new dampers which should be fitted in pairs. (Fitting a new damper on one side will highlight wear in its opposite number, and may cause handling problems.) As with many other car parts, shock absorbers are available in a range of prices which equate with quality. If your car has a limited life remaining, there is little point is buying the best - budget-price items will generally serve for the short to medium term.

Exhaust & emissions

With engine just ticking over, listen to the exhaust. Any puffing or blowing means a leaking joint. Anything louder probably means a split pipe or muffler box. Check further by momentarily blocking the open end of the exhaust pipe with a gloved hand or a ball of rag. The tester will do this, and it certainly shows up very small leaks as the gas pressure builds up. If repairs needed, it's usually best to replace the entire exhaust system. If you replace just the front or rear section, you run the risk of damaging other exhaust components in the process. Exhaust emission requirements get tougher each year. The actual test requires expensive specialist equipment and therefore has to be left to the MOT test station. But a basic check is to see if there is any smoke leaving the exhaust when engine is idling, followed by testing at medium revs (around 3000 rpm), watching for any puff of smoke as the throttle is released. You'll obviously need a helper to carry out these tests.

Blue smoke is a bad sign it means engine oil is burning in the cylinders, and usually points to serious wear. The remedy could be as simple as new valve stem oil seals; on the other hand, an expensive rebuild or fitting a reconditioned engine may be the only solution. Black smoke means too much petrol is being burnt, while clouds of dark grey smoke may point to an out-of-tune diesel engine.

If you're lucky, either fault might be put right by as little as a twist with a screwdriver on the carburettor screw, or fitting a new air filter. On the other hand, exhaust smoke could mean the carburettor needs replacing or the fuel injection system requires expert attention. The latter is especially likely with a diesel engine.

Tyres

Tyres are a common fail item but are easy to check. The minimum requirement is 1.6 mm of tread depth showing in the pattern all the way round the tyre and over three-quarters of the width. No breaks, gaps or low spots are allowed. This figure is a bare minimum - it's safer to replace tyres before they reach this limit. There must be no cuts, splits or serious cracks in the tyres side-wall. If any are seen, you need a new tyre. It's easy to inspect the outside wall of all the tyres, and similarly the tread depth it's obvious if there is plenty there or if it's marginal. If the latter, it is advisable to jack the car up and spin the wheel round to inspect the complete tyre and make a decision on whether to replace it.

Looking at the inner side-walls probably also means jacking the car up and peering underneath with the aid of a torch or inspection lamp. Warning: If the car is on a side jack, never put any part of your body beneath the car unless there are axle stands in place. Unless they're on a hard level surface, car side jacks are renowned for slipping out and letting the car drop. Even then they are not to be relied upon. So don't risk it there have been many accidents where home mechanics have got trapped under cars. The spare tyre must also be included when doing the above checks. The tester will check for signs of high or low tyre pressures. Too high and there is less tread pattern showing in the centre of the tyre, too low and it is the outer edges which wear most. Many cars tend to wear their tyres slightly unevenly, but such wear is apparent only towards the end of the tyres' life. If any unusual or dangerous pattern of wear is spotted during the MOT inspection, the tester should advise you.

Lights

The biggest single cause of MOT failures is the car's lighting system. Lights are easier to check on a dull day or when daylight is fading.

SIDELIGHTS: two white at the front; two red at the back. Should be bright and of equal intensity. Look closely at the rear lights to see if there is a dim glow from the brake lights, turn indicators or high-intensity fog lights this may mean a poor earth to the car body on the nearest sidelight. If the front sidelights are small bulbs set in the headlight reflector these may be dim these little bulbs tend to overheat and go black inside. Not a fail point as such if they are both equally dim, but it's best to replace them.

HEADLIGHTS: Put the headlights on dipped beam. Both should shine with equal brightness failure to do so means a bad electrical supply or earth at that bulb. The reflection from the lights on a wall or garage door should show the two beams pointing slightly down to the left and level.

There are adjusting screws or knobs behind each headlight, but unless a beam is so far out of line as to cause a hazard, it is probably best to leave adjustment to the MOT tester, who will usually use a beam-setter to set them spot on.

Switch to main beam and make the same check the beams should be higher and central.

REAR FOG LIGHT (S): Switch on the high-intensity red rear light(s) your headlights need to be on dipped beam. If fitted, fog lights must work, so must the interior 'tell-tale' light on the instrument panel.

TURN INDICATORS: Turn the ignition on and operate the indicators. Check that there is a flashing 'tell tale' light on the instrument panel. Check that front and rear indicators are flashing. The flash rate should be between 30 and 90 per minute. If it's just under 30 it may speed up once the engine is running, though not if the flasher unit is an electronic rather than a mechanical unit. Side repeater indicators on the wings must be working if fitted.

HAZARD LIGHTS: With the indicators off, switch on the hazard flashers, checking for the warning light and/or tick inside. Walk round the car to ensure that all four hazards are flashing, and that no other lights are glowing dimly. Switch off hazard flashers.

BRAKE LIGHTS: Get a helper to operate the foot brake while you check the brake lights. Again, both brake lights must be equally bright, with nothing else glowing. Switch off the ignition. Then test the horn.

LIGHTING REPAIRS: If a light isn't working, chances are the bulb is blown. Bulbs are standard items, so replacement is easy. Indicators and rear red hazard lamp bulbs are 21 watt; brake light and rear tail light are usually a 21 and a 5 watt combined into one bulb. This only fits one way round to ensure the brake light is the more powerful. If it doesn't slip in easily, don't force it! Ensure that the offset pins match the slots in the bulb holder. Front sidelights are either small bulbs set in the headlamp reflector, or larger bulbs (around 5 watts) under separate covers. Headlight bulbs come in various fittings and types, so take the old bulb along when buying a replacement. Access to the bulbs is gained by either unclipping the bulb-holder from the back of the light housing (usually after removing a cover) or by use of a number 2 Pozidriv (cross-head) screwdriver to unscrew the coloured lens from the outside. If you have a vehicle handbook, it may show the correct procedure for removing and fitting bulbs. Other reasons for a bulb not lighting may be broken or badly corroded wiring. If one lamp lights up another, check for broken or corroded wires or a damaged lamp-holder and replace them. Many rear light units are mounted on a printed circuit board. If the circuit strips corrode, a new unit will probably be needed. Front sidelights are either small bulbs set in the headlamp reflector, or larger bulbs (around 5 watts) under separate covers. Headlight bulbs come in various fittings and types, so take the old bulb along when buying a replacement. Access to the bulbs is gained by either unclipping the bulb-holder from the back of the light housing (usually after removing a cover) or by use of a number 2 Pozidriv (cross-head) screwdriver to unscrew the coloured lens from the outside.

If you have a vehicle handbook, it may show the correct procedure for removing and fitting bulbs. Other reasons for a bulb not lighting may be broken or badly corroded wiring. If one lamp lights up another, check for broken or corroded wires or a damaged lamp-holder and replace them. Many rear light units are mounted on a printed circuit board. If the circuit strips corrode, a new unit will probably be needed.

LENSES & REFLECTORS: Headlamp reflectors must be bright and not obviously misted, tarnished or corroded. The headlamp lens should not have any hole or a crack that could let in water. All plastic lenses covering the other lights should be the correct colour and not excessively faded. Slight fading is allowed, but both lenses must be equally affected.

Brakes

Look also at both the metal and flexible rubber brake pipes going to the brakes. Minor surface corrosion of the metal is allowable, but there must be no cracks or visual deterioration on the flexible pipes. If possible, ask a helper to press the brake pedal hard while you hold each flexible pipe -if you can feel the pipe swell, it is in need of urgent replacement.

Wheelspin Feb 2002

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