Wednesday, August 11, 2010

Carburetors are Less Scary


This is actually one of the scariest things I have done to my VW.  With help from my friend Dave (made famous in an earlier post), I completely disassembled the carb.  I replaced gaskets and seals, and gave everything a thorough cleaning followed by some quality time with an air gun.

Learning experience: when the instructions say "Pay attention to how this spring was installed" what they really mean is "put it back the same way."  I didn't, and as a result my accelerator pump wasn't working, and the Thing really wouldn't run at all.  Dave deduced that the accelerator pump wasn't working so something must be wrong in that area, and he found I had put the spring in backwards.

Dave was also kind enough to check and adjust my valve clearances. They should all be 0.006, and some were a little off. In particular, #3 had very little clearance at all. This is a problem because it means the valve doesn't sit closed long enough to allow its retained heat to conduct through the head. This can lead to valve failure and horrible engine damage. I'm noting the valve clearances before adjustment here; if we find that #3 is consistently getting too tight more drastic action will have to be taken.


Cylinder Valve Clearance (inches)
1 exhaust .005
intake .003
2 intake .006
exhaust .004
3 exhaust less than .002
intake less than .002
4 intake .004
exhaust .003

3 comments:

  1. Hey Chris,
    Thanks for the mention. The order of the valves are exactly how they are in the engine. All of the outside valves are exhaust and the inside ones are intake, appropriately enough. Make sense? So on number one the first valve is exhaust, the second, intake. Number two, the first is intake, the second exhaust. Number three, the first is exhaust, the second intake. Number four, the first is intake, the second exhaust.

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  2. I think so, but I'm not 100% sure I got it right with respect to your notes, because your notes go "up and down" not "in and out"

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  3. You have done a good job with your knowledge that makes our work easy because you are providing such good information. Keep sharing this kind of knowledge with us. Tuning Performance Car Parts Online UK

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