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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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