I once owned an old Mercedes and a corresponding Haynes repair manual that was almost of the same vintage. It caused me great grief that the images in it were of such low quality. Essentially, they seemed to have cut costs by employing the cheapest possible print process, which made it unclear how the smudgy photo I was viewing in any way related to the guts of my ancient auto. Why on earth don’t they just film a DVD as they document each task? That way, you could hear the background grumbling and swearing that always accompanies any kind of maintenance session -a refreshing source of forewarning about the weekend ahead.
Anyway, my theory about DIY car maintenance (who can afford to have a garage do all the work?) is that the main difficulty, apart from recognising the bits, is not knowing how hard to press, pull, squeeze or rotate.
If you haven’t ever seen inside that bolted-in enclosure, then it’s always a concern that you may be about to strip some expensive threads or deface a highly-priced casing or, worse still, render the whole vehicle immobile by the slip of a screwdriver used as a poorly-positioned lever. This situation is made even more difficult by the grime which covers everything and tends to gum up all moving parts.
Today’s invention then is simply an addition to all repair manuals consisting of a force rating scale. Each task would be labeled, by someone who has actually done it, with a coarse measure of how much effort is required to perform it. This scale might be as crude as a series of enjoinders: “lubricate first with DWF then easy”, “often sealed by corrosion, fiercely hard work”, “no more than two blows with a rubber mallet”, “requires extraction of whole unit first” or “best left to an expert.”