[Vwdiesel] More Quantum Questions?

[Erik Lane]

> From what I can see, you have dropped a valve, turned engine until piston
> rested on the valve, made a reference mark on the timing beltat some
> convenient reference point. Then turned engine back the other way until
> piston has again com to rest on the valve. Then made another mark. These 2
> marks are about 8" apart. Bisecting gives you the mid point.
> What you have efectively done is measured the circumference of the crank
> timing belt sprocket, less the missing bit due to the valve. Circumference
> being Pi x D, thus approx 3 x 3 or 9" . The missing bit is actually bythis
> method roughly 9 -8 or 1". The 1 " actually would lie 1/2" beyond your two
> marks on the belt, and NOT the mid point of 4" from either mark towards the
> other.
>

I see what you're trying to say, and it's possible, but not necessary. In
your calculations you assume that he has a valve at either cylinder 1 or 4
blocking the piston. If instead a valve at 2 or 3 is blocking it then his
measured midpoint should indeed be the TDC, and since he used a wire through
the injector hole to dial it in even closer I would believe that this is
what happened.

Erik