Re: [T3] Too much advance

[Jim Adney <jadney@vwtype3.org>]

On 10 May 2004 at 16:17, Mark Seaton wrote:

> Doh!- none of us noticed that the vw charts are adjusted so they start at 0
> deg advance- my figures were actual advance figures (starting at 7.5 deg) So
> it looks like theres not much wrong with the mech advance at all.

Okay, that makes sense. In general, Timing refers to the point where the spark 
occurs, while advance refers to changes in the timing. Dist graphs are done 
without knowing how the idle timing will be set in actual use, so they only 
refer to advance; thus they all start at zero.

> I re-checked my vaccuum and I think I must have had a leak when I took those
> readings. Yesterday I hooked up the gauge to the can via a tee and just
> sucked on the line while looking at the advance with the strobe and I can
> say that the vac adv stops at about 16cmHg which is not so far from spec.

Yeah, leaks in vacuum lines can make a big difference.

> So my dizzy looks OK, but the engine still runs better without the vac. I
> guess it must be something else- like the vacuum source/characteristics
> being wrong.

So we're back to being puzzled....  8-p

This may be odd, but there are a lots of possible explanations: Perhaps the 
stock setting was intended to meet some emissions spec, or maybe your pulley is 
not installed right. Have you tried to verify the TDC timing mark?

> Sorry this seems to have been a bit of a red herring.

Don't apologize. You did all the work and we just got to sit back here and 
learn something.

-- 
Jim Adney
jadney@vwtype3.org
Madison, WI 53711-3054
USA

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