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So if you read that right they say that you had 6 valves that were too loose and needed a thicker shim to bring into spec, correct? If so then that makes sense, from time to time you will find one that is a little too tight but more often then not you find loose ones. Less face it as things wear in they don't get tighter, the clearances increase and you need a thicker shim to take up this slop.
This was done less than 5Km ago, that is in the area of 3100 miles right? The only logical conclusion that I can come up with is that there numbers are bullshit. I cannot tell you how many times that I have seen people change valve cover gaskets on a 30,000 mile service and say that they adjusted the valves when in fact they did nothing more than change the gasket. The majority of the time the valves are either right on the money anyhow or not far enough out to be a problem. Usually you will find that there are 1-2 valves that are out of spec, none of them out of spec or 6-8 or them out of spec. I know it is odd but that just seems to be the way it is. I would like to think that if you brought the car in for a valve adjust, not a 30K service where the adjust is supposed to be part of it, that they would at least go to the effort of actually adjusting the darn things.
Why do I like to adjust them hot? To reasons 1) that is the way I was taught to do it. 2) How is it that you drive the car, at operating temperature I pressume, and if so then does it not make sense to have the valves set to the correct setting for the temperature at which they will be used for the absolute majority of the time. Furthermore, when you are in a busy shop it really is not practical to have to cool off every motor that you adjust valves on. Some cars there is no other way to do it. If you adjust valves on a BMW M10, M20, M30 motor hot you are going to be redoing it the first time the customer starts it up cold and it clatters and runs like crap. But we are working on Volvos here and they respond just fine to having the clearances set on a warm motor at .016-.018"
You ask how warm? Well if I pull a car in and it is smoking hot I will usually let it cool off just a little bit but not much. It really is a feel thing. When you have adjust 100's if not 1000's of valves on these motors you get a feel for it. You know that when the motor is a little on the cool side that your clearances are going to be on the tight side. Conversely, when you have to work on one that is absoluteyl blistering hot you know that things are going to be a bit on the looser side. What this means is that if it is blistering hot and you run across a valve that the .018 fits in but the .019 won't then you don't adjust it and the same is true on the other end where you find a .015 that fits on a cooler engine but the .014 won't you let it go. I realize that does not do you a lot of good seeing as how it is kind of a perceptive deal that is acquired over years and years of doing this operation but that is how it is. The best advice I can give you is if it is blistering hot I would let it cool down 20 minutes or so, if it is cold I would start it up and let it idle until it reaches operating temp and then shut if off and check/adjust them.
It is funny what you say about reading the numbers off on your feeler guages, now that I think about it my feeler guages are all set up like that too. Why they put the third decimal place on a metric guage is beyond me but if I had to guess I would say that they just were not familiar with how fine a thousandth of a millimeter really was when they did it.
Mark
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