Kim Henson advises ensuring that the wheel arches and underbody structure of your car are kept clean, to prolong its life and make it more pleasant to work on.
Recent wet weather in Britain has resulted in many roads being strewn with mud, accumulations of leaves, etc. Inevitably these deposits are transferred to the undersides of passing vehicles, via their tyres. In turn the resulting debris that builds up beneath the vehicle can hide potential problems from view, make routine maintenance unpleasant and more difficult, and in the long-term can encourage corrosion to take root.
All such problems can be avoided or at least minimised by the routine removal of such silty deposits. If you have a pressure washer, this can be helpful to lift and remove the ‘mud’ (which often includes harmful road salt, in the winter months), but be VERY careful. The use of a water jet at high pressure can take off paint or underbody protectant as well as dirt, which will allow a way in for rust to start in the steel thus exposed. There’s also a danger that water applied under high pressure can enter electrical units or connections, dislodge brake sensors (etc.) and flood the brakes…
Be careful where the water jet is aimed, and avoid sensitive components (ideally wrap them in waterproof coverings before you start). If your pressure washer has an adjustable setting, try operating the machine on its lowest possible pressure.
Alternatives include the use of a hand-operated pump/reservoir unit designed for garden use (these often have adjustable spray heads – very handy), and the manual application of a soft-bristled brush, dipped in water (ideally warm) to free deposits from the vehicle. I find that the use of ‘car shampoo’ in the water helps to float off the dirt; rinse off with clean water.
I find that the use of a very short-handled brush enables easy removal of dirt from the under-wing areas, including the ‘ledges’ usually found around the inner-faces of the outer wings. These harbour deposits of mud and salt, that if left in place can encourage rusting. Clean out the mud traps often found in the lower corners of the under-wing voids too, and ensure that the sill structures are included in your efforts.
I often use the above methods for a quick yet effective means of keeping clean the wheel arches and other vulnerable areas, especially during the winter months.
Of course, for improved access and a more comprehensive job it is helpful if the car is raised and securely supported (on axle stands) and the wheels removed, but this is not always possible. Even with the wheels fitted and the car standing on the ground, much cleaning can be done within a few minutes at home.
If you are unable or unwilling to carry out such operations at home (and maybe you don’t have a driveway in which to work), many public car washes incorporate an under-body lance that can be used to do the same job.
Of course, keeping the upper bodywork of your car clean (and polished) will help it to survive and look good for longer too.
VERDICT
Whether your car is old, new or classic, keeping its underbody free of muddy accumulations costs little in time and effort, is very beneficial and can add years to its working life.