A clean engine compartment is very important, not only for established motor mechanics. Some workshops begin an extensive repair, depending on the state of the engine compartment, with a clean-up. It's not only the old-timer fans who place a great deal of importance on a visual examination to expose possible patches of rust, thus, a well cared for engine compartment is highly valued. So far, so good.
Have you ever wondered, why washing your car in your own driveway is, as a rule, not allowed? You may argue that the rain washes the dirt off the car anyway. This is, without a doubt correct, although, not as thoroughly as you do, e.g., when spring-cleaning.
This is precicely the reason, why one should limit the cleaning of the engine compartment to a minimum. Certainly, there are repairs where dirt in the engine compartment can be a real handicap, particularly if it is still wet. Checking the sealings, e.g., is virtually impossible without first cleaning up. An intensive checking for rust patches, at reasonable intervals, can also be wise. Certainly, this appeal won't prevent the fans of chrome-plated cylinder head covers or even gold-plated engine parts (see figure 3) from doing their thing.
At this point we assume, that you are familiar with the rules of accident prevention when using high-pressure cleaners and that other employees are not endangered by the strong, also those deflected, jets of water. At the same time of course, paying attention to your own protection. The fact that you are working over a petrol-trap is taken for granted.
That, as far as possible, the electrical functions are switched off is, once again, assumed, nonetheless, care must be taken with possible dismantlings. It may be necessary to do extensive follow-up work, e.g., on the battery, this should be cleared up before you disconnect.
We now come to the subject of 'strong jets'. High-pressure cleaners, also those designed for domestic use, can cause unbelievable damage. By spraying directly onto a tyre from a short distance the tyre can be so deformed, that further high-speed driving on the motorway can be really dangerous.
One distinguishes between flat-sprayers, those up to 80 bar, and those over 80 bar, whereby the latter are far more dangerous. Think about it carefully, whether the short distance is necessary and whether the component being sprayed is perhaps, designed as a protecting oil-seal for a bearing, the protective sleeve of an electric connection or for the protection of a universal joint.
There are various openings in the engine compartment, where the designers have not reckoned with direct high-pressure jets. Even large components are endangered. Why do the manufacturers allow a radiator testing pressure of maximum 1,5 bar, when you have a go at this part with 80 bar? Be careful, rather save yourself the possibility of follow-up repairs.
Do not believe, that washing the undercarriage is any less stressful.
The chemical side of your activities is also not to be underestimated. Where do the additives found in the steam-jet go? What does your car smell like the next time you use it? Are there afterwards, perhaps malfunctions caused by not completely removed additives? As you can see, in all cases, rinsing out is very important. 06/09