As some of you may know, I am what you might call a ‘born again mechanic’… many (many) years ago I used to play with cars, take them apart and put them back together etc. Over the past 15-20 years I moved away from all that and stuck to dealer service. In part due to family and work constraints, as well as lose of interests, and in part due to the cars I owned being under warranty anyway.
Secretly I was still reading the likes of Car Mechanics Magazine, until I finally re-introduced myself to the wonderful world of DIY car mechanics in mid 2005, when I found the other site after looking for advice re the cambelt change (basically I didn’t believe the Vx dealer that the belt need doing at 40k/4y when the service book said 80k/8y.. I was wrong of course).
I would like to share with you my views on how the whole thing has changed… car mechanics used to be an art form (I kid you not), and now that art is lost… forever. Let look at a few very basic service procedures.
Let’s say I wanted to clean the carburettor. A perfectly sensible thing to do from time to time. You take the thing off, take it apart, dose it in carb cleaner (or petrol), give it a good brush down and put it back. While you’re at it, you need to adjust the float. Remember those drawings in Haynes? You hold the lid at 90 degrees and let the float rest on its valve, then measure the distance between the widest point of the float and the end of the lid gasket. Then bend the float arm to adjust as necessary. Next thing the jets. On high mileage engines, it was always advisable to check the jets hole side using a set of measuring rods, because the jets were made of brass or copper and tended to become wider with use. Once the thing is back in place, you need at the very least to adjust the mixture and idle speed if you have a single-carb engine. If you had a pair of SUs or Strombergs, then there was an additional balance screw to adjust (and let’s not talk about the needle in these carbs…). But if you happen to have a pair of dual-barrel Webbers, or perhaps a triple of those, then you were in for a very lengthy job involving vacuum gauges and witchcraft…
Next, let’s say you take the distributor off. You then put it back (making sure it’s the right way round because you could easily put it on turned at 180 degrees!), then clean the points with emery cloth and adjust the gap with a filler gauge. Then loosen the bracket and set the engine to TDC and the dizzy to the Static timing mark. Start the engine, and using a strobe set the dizzy for the correct advance at the specified fast-idle and high-rev speeds. Lock the bracket, take the car for a spin. Drive it on level ground at low speed in low gear without revving the engine. Then put it in fourth, and floor the accelerator. The car should pink just a bit but catch up without hesitating. Then drive the car downhill in high gear, and put it into low gear suddenly revving up the engine – it shouldn’t backfire. If you got this right, you had the car at the optimal timing advance settings. Until it all went out of tune a couple of months later, that is.
Camshaft out? The tappets need adjusting with a filler gague (or spacers, which was much worst). Change brake pads? Filler gauge again. Everything was down to adjusting and fine-tuning and getting it right. In the U.S. they still call it an engine ‘tune-up’, not service.
Torque wrench was only used when putting back the cylinder head, for everything else the mechanic had a 4-way table in his head which takes into account the bolt size, the lever size, the metal it went into, and errr… the direction of the wind. Well OK, not the last one... You needed to have a ‘feel’ for tightening bolts which was only acquired through experience – in other words through some stripped threads on one side and loose bolts on the other.
Why am I saying all this? Well during Easter I did the cam covers. I took off the plenum and intake manifold with the injectors rail, then put it all back together. The ‘tuning’ comprised of un-plugging three multi-plugs (two, if you don’t have Drive-by-Wire) and then plugging them back in. All the bolts were tightened to torque, fire-up the engine and it purrs like a kitten, just as it was when it left the factory. Steady idle at 500 rpm, nothing to measure, adjust, or fine-tune. No drama, not black art, no magic. A bit of an anti-climax, that is. Yes, you could say it was boring.
I guess it is better this way, and the garage mechanics have less room for error. For me, I still have to get used to this. So what’s the difference nowadays between a ‘good’ mechanic and a 'bad' one?
Author
Topic: Where's the magic gone? (Read 854 times)