WAS: advise or help needed >> now Project Execution and Strategy

[Orin Eman]

Thanks Javad.

> The secret??  Well, its the vaunted theory of K.I.S.S. (keep it simple
> stupid) - generally speaking.

Absolutely!

Now, since I actually have some time today...

>  I need to understand the output of the hall sensor, relative to crank
>  location.  Apparently this entails the use of many items that I don't
>  have possession of or experience with their use.  My current
>  understanding, from emails and postings, is that the hall sensor
>  output is normally "high" (at 5 volts?) and "low output" window is 40
>  degrees wide, and this window is centered (when the distributor is
>  indexed where it should be) on the flywheel pin location of 62
>  degrees BTDC.  One specific clarification I would like is whether
>  this is on the 360 scale of the crank, or is it on the 360 scale of the
>  distributor itself.  I would imagine that it is the crank, but since I
>  can't measure jack-sh!t currently, I can't confirm anything.

On a 4 cyl dwell meter, it measures 5 deg.  That's 5 out of the dwell
meter's assumed 90 degrees, or 20 out of 360 degrees at the distributor,
therefore 40 out of 720 crank degrees.  That's all I used to get the
40 degree number.  Oh, they are rarely 'centered' on the timing pin.
As long as the timing pin signal occurs during the hall sensor window,
the engine will run.

>  In order to determine physical TDC accurately, it seems I need a
>  dial indicator and a suitable mounting base, to make direct contact
>  with the piston to find where it is located.  I need help here, both
>  with locating and choosing the correct tool, and with learning to
>  use it properly.
>
>  In order to determine crank position, I also apparently need to
>  locate and learn to use a degree wheel.  These items apparently
>  get attached to either a crank pulley or the flywheel, and tell you
>  how far you are rotating the engine.

Why?  There is a zero on the flywheel which indicates TDC on cyl 1.
The timing pin is 62 degrees before TDC on cyl 1.

If you are going to be using the distributor for timing, dial
gauges etc aren't going to help... you need to be thinking
timing light once the engine is running.  If you are worried about
timing sequential injection, it really doesn't matter that much - totally
irrelevant at high load and only really affects emissions at low load.

>  I'd love to hear that I'm wrong about how complicated this is, and
>  that there is either some other way to get the information I need.
>  For example, it was said that SJM's site had the o-scope
>  waveforms of the hall sensor.  I didn't find that, I only found the rpm
>  and timing reference sensors output waveforms.  Does anyone
>  know where I can find a waveform of a hall sensor output?

Just a rectangular wave.

>  If anyone has the ability to measure the output of the hall sensor,
>  and is willing to do so, will you please contact me or post to the
>  list?  Maybe that's what I should ask?

It's all above.  Low for 40 out of 720 crank degrees.  Pulled up
to 5V by the ECU otherwise.

Orin.