DIY MOT

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Rob Hawkins provides an overview of the MoT checks that can be conducted at home on your classic to keep you safe and legal

Whether you intend to submit your classic car for the annual MoT test or not, many of the checks that are included in this examination are straightforward to conduct at home and worthwhile to help ensure your vehicle remains safe and roadworthy. With so many classics being 40 years or older, the temptation to register them as MoT exempt is always going to make life easier, but we don’t recommend this approach. If you’re confident that yours is roadworthy, then why avoid the test? Similarly, if you are awakening your classic from a winter hibernation, it makes sense to thoroughly check your vehicle over before taking to the road. Chances are that the ‘ticket’ has expired anyway so why bother to have the minister test carried out if you think it may result in a fail slip.

Back to basics

With the exception of a brake performance test and emissions test, most of the checks that are conducted in an MoT test can be carried out on a DIY-level. Many of the aspects of the examination are dead easy to check and no doubt subconsciously checked when the vehicle is driven. For instance, checking that the seatbelts lock and inspecting them for damage, the doors can be opened from the inside and outside (child locks on rear doors mean they are not tested from the inside at the MoT) and controls such as indicators, headlights, foglights and other exterior illumination work as they should, are all aspects that are pretty much verified each and every time that we use them.

There are a few points to be aware of when it comes to exterior lighting checks. The speedometer for instance, must be illuminated when the headlights are switched on. A main beam telltale must appear on the dashboard, such as a blue light, on vehicles registered after 1st April 1986. A foglight must be fitted to vehicles registered after 1st April 1980 and a warning light must illuminate on the dashboard. Problems with telltale lights not appearing on the dashboard are often due to blown bulbs or faulty wiring, which can be time-consuming to fix, especially if it means dismantling the dashboard. In some cases, it may be easier to fit a new switch with its own illumination. Specialists such as Europa Spares and Car Builder Solutions stock a range of universal switches that can help to fix such problems.

Whilst checking the exterior lighting, inspect the indicators to make sure their orange glow hasn’t faded. Where an orange bulb is fitted, the orange exterior of the bulb eventually fades and burns off, so the bulb will need to be renewed. Orange indicator lenses can also become bleached by sunlight and will either need to be replaced or equipped with an orange bulb.

There are several straightforward exterior checks that can be conducted in a few minutes. Check the condition of the windscreen wiper blades, looking for cracks in the rubber. Ensure the windscreen washer fluid reservoir is topped up, then operate the wipers and washers to check they work properly and the wipers clear the windscreen. If the washer jets are blocked, try cleaning them with a dressmaking pin. If the wipers drag over the screen, polish the rubber.

Look over the windscreen for signs of damage. There’s an official template that helps to determine whether a crack in a windscreen will fail the MoT test, but as a rough guide, a crack that’s greater than 10mm above the area of the steering wheel and in the line of view of the driver will fail, and anything outside this area that’s within the sweep of the windscreen wipers must be less than 40mm in length.

There are a number of MoT points that can be conducted whilst sat in the driver’s seat. The aforementioned checks of the lighting controls and their telltales are some of them. On modern classics, look for dashboard warning lights relating to the anti-lock braking system (ABS), airbags and supplemental restraint system (SRS). These warning lights must illuminate when the ignition is switched on, but not remain on.

Some modern classics have a warning system for low brake fluid, which illuminates the handbrake symbol on the dashboard or a separate warning (this may also be used for the brake pad wear indicators). Such warning lights must not remain illuminated.

If the driver’s seat can be adjusted fore and aft, make sure the seat locks into position and cannot move once locked. This also applies to seats that are adjusted electronically.

Whilst sat in the driver’s seat, check the steering wheel by waggling it up and down to see if there is any play in the steering column bushes. Turn the steering whilst looking at a front road wheel (where power steering is fitted, run the engine). The steering can be turned by up to 13mm before the wheels move (up to 48mm if there are several joints between the steering wheel and rack) and 75mm for a steering box.

On vehicles registered after 1st September 2001, if a steering lock is fitted, check that it locks when the ignition key is removed (turn the steering a little to lock it) and unlocks when the key is inserted and the steering turned.

One aspect of many classic cars that is often seen as problematic concerns the handbrake. It’s often either ineffective or if it’s adjusted too much, it drags and overheats the respective brakes. The correct adjustment is essential, which usually starts with slackening off the handbrake cable before adjusting the brake shoes or checking the ratchet mechanism on a disc brake calliper is free and correctly positioned.

Once you are confident the brakes that are operated by the handbrake are correctly adjusted and working properly, the handbrake cable should be adjusted to take up any slack in it. As for the MoT test, the examiner will check that the handbrake can be applied and that it remains in the up position (unless it’s a fly-off handbrake), followed by checking that it can be released. The brake test will reveal whether it is sufficiently effective.

The fuel cap will be removed during the test to check the rubber seal around it, because if the seal is damaged, petrol fumes can leak out. This is an easy enough point to check.

The tyres are straightforward to inspect and should be examined on a regular basis anyway. Start by looking at the sidewalls to see if there are any bulges, cracks and damage. The depth of the tread is checked at the MoT test, and there are various differences to whether a tyre passes or not, depending if tread wear indicators are fitted (small blocks of rubber between the tread blocks that help to show when a tyre is worn to the limit). However, as a general guide, ensure the tread is at least 1.6mm deep across 75 per cent of the tread (the central three-quarters). It’s worthwhile investing in a tread depth gauge to help measure the tread although if you have to check it that precisely then surely the time to replace the tyres is now?

The checks outlined so far are relatively straightforward to conduct and don’t require you to venture underneath the vehicle or get your hands dirty. However, a thorough underside inspection is essential.

Down and dIRTY

If you have access to an inspection pit, a lift or ramp or even drive-on ramps, these all help to inspect the underside of a vehicle. At the very least, a trolley jack and axle stand will help to raise and secure one corner of the vehicle at a time to be able to waggle the road wheel and check for play in the suspension and steering bushes and wheel bearings.

A pry bar can also be used to lever against the suspension bushes and check for excessive play. And a visual inspection of rubber bushes, dust covers and gaiters will help to identify any that are split. Any that are split will only fail the test if they are deemed to be letting in water and dirt, which can damage the component (e.g. a ball joint) inside. Our advice is to renew such a cover if it is cracked.

Corrosion is perhaps the biggest threat to an MoT failure on a classic car and also the biggest problem in general. Armed with a light hammer or blunt screwdriver, tap along the underside and inside of the sills, crossmembers and chassis sections to ensure the metalwork creates a reassuring tinny noise to suggest it’s intact. Rotten metal will make a dull or crunching noise.

Corrosion is generally inevitable and in some cases, it won’t fail the MoT, but it’s wise to be aware of it and have a plan for how to fix it before it spreads. And corrosion goes beyond the bodywork of a vehicle, so check the brake and fuel lines are rot-free and securely fitted. Look at the suspension arms, dampers and mounting points for excessive rust – on the MGF for instance, the front lower arms are known to rust through.

One aspect of the MoT test that cannot be conducted on a DIY basis is the emissions test. Depending on the age of the vehicle, there are a number of rules concerning this test, which are dependent on the age of the vehicle and its type of engine, ranging from a mere visual check to specific levels of hydrocarbons (HC), carbon monoxide (CO) and oxygen (lambda). To help pass this aspect of the test, ensure the engine has been serviced with oil, filter and spark plug changes conducted at the recommended intervals. Check the exhaust system for leaks, which can contribute to increased emissions. For vehicles with sensors such as lambda (oxygen), mass airflow and air temperature, check these have not logged any faults that can result in high emissions and result in a fail.

The brake test is another aspect of the MoT test that cannot be checked at home, but just like emissions, a thorough service to ensure it’s in good working order can help.

We can’t guarantee a pass, but at the very least, you’ll be more confident with the condition of your classic car and less nervous of an unexpected fail sheet.