All,
In my last post I showed the ignition/injection pulses and explained HOW they are created.
So, what’s next?
How does all that relate to an engine?
More importantly, how is it APPLIED to an engine??
THAT is the subject of this post!
Remember one of my earlier attachments, a file named “engine timing 2.pdf�
(4 stroke engine timing cycle)
If not, I suggest you go back to my post (reply # 166) it was attached to, save it and PRINT it!
Now put that drawing on your desk and turn it about 30 degrees anti-clockwise.
(So that the line with the markings of 270 – 0 – 90 – 180 – 270 degrees which was horizontal before, now is on an angle, RISING to the right!
That rising line you now see is the SAME as the ‘slope’ of the saw tooth in those oscilloscope images in my last post!
Just for the readers of this Forum (yes, both of you!

) I have made an additional drawing which, together with the previous one, may lead to better understanding of this subject!
For those who are prepared to “get their hands dirtyâ€, I can offer some general suggestions on how to set up this ignition/injection system on your engine.
Make sure you understand and follow these instructions closely!
If you don’t, you will not only end up with a non-working system but also run a real risk of doing DAMAGE to your engine!
(I like to draw your attention to a post made by ‘bolt’ earlier in this thread:
“if you don't change the timing the engine runs like a pig, back fires, can bend valves and can burn hole in piston. Plus it requires a HUGE amount of gas just to barely run. When properly tuned and blank spark sorted all these issues vanish.â€)
By the way, a properly set up fuel injection virtually ELIMINATES back fires!That does NOT mean that you should operate your set-up without a flash back arrestor!
IMO, you should NEVER, EVER operate ANY kind of system running on HHO without an appropriate flash back arrestor!
It is the “life insurance†of your electrolyzer and perhaps your entire system!
OK.
First, REMOVE the fuel tank, the carburetor (only if you want to use injection) and the ignition module (which most likely includes the coil) PERMANENTLY and the valve cover AND the spark plug TEMPORARILY!
* There are two reasons for removing the spark plug:
1. It will be MUCH easier to turn the crank shaft by hand as there is
NO compression when the cylinder is OPEN!
2. It is easier to determine when the piston is at TDC and BDC.
For BDC you may have to use a ‘stick’, (through the plug hole) placing one end
of it against the top of the piston.
* After you have removed the valve cover, identify the EXHAUST valve and its rocker
arm.
Since this arm is most likely made of steel, the magnet will stick to it.
Once you have determined the TYPE, SIZE and the POSITION of your magnet and it
operates the Hall switch properly, it can be glued to the arm, using HIGH temperature
Epoxy resin.
Note: we may (or may not) get away with using ‘Neo’ magnets.
It will depend on how hot (or cool) the engine will run with ONLY HHO.
‘Neo’ (Neodymium-Iron-Boron) magnets start losing their magnetism above 150°C!
We may need to use Samarium-Cobalt or even ‘Ceramic’ magnets (which can “take the heath†but are not as strong as ‘Neo’s).
* Make a mounting bracket for the tiny Hall switch circuit board and attach the
assembly TEMPORARILY to the engine block in such a way that you can easily
ADJUST its position.
* Apply 12V DC (with the correct polarity!) to the Hall switch circuit.
In the absence of a magnetic field, the LED will turn ON at power-up.
(This may only apply to the Melexis Hall switch I use.)
* Now turn the crank shaft by hand and watch the movement of the rocker
arm with the magnet AND watch the indicator LED!
* The physical POSITION of the piston where the LED turns OFF, corresponds with the
vertical “retrace†line at the START of the slope you see in the saw tooth waveform!
The purpose of the process I just described is to find (in degrees of camshaft rotation) the physical position of the piston when the pulse from the Hall switch arrives!
From there on, from this single pulse, our electronics is first going to derive not just one but TWO different pulses (ignition and injection) and then place them EXACTLY where they need to be!
(The details on how this is done is explained in the circuit description.)
A few words about the new drawing:
The large RED dots on the slope indicate the TDC and BDC positions of the piston.
The 4 BLUE dots are half-way position marks (45°) in each of the 4 cycles.
The BLACK dots mark each 10° of CAM shaft rotation.
Dotted lines (GREEN and PURPLE) indicate the limits of the injection and ignition pulse positions.
BLACK dotted lines show that the Hall switch pulse length is almost the same as the opening time of the exhaust valve.
The RED and BLUE horizontal lines intersecting the 30° slope of the saw tooth are the voltages applied to the ignition and injection comparators, respectively.
Both pulse POSITIONS on the slope are adjusted by varying these voltages!
THE POINTS WHERE THESE LINES INTERSECT THE SLOPE INDICATE THE PISTON’S POSITION IN THEIR RESPECTIVE CYCLES! More to come…..
Best regards,
Les Banki