I just found this old post, has anybody ever heard of this before and can I try this Nova II module?
Where do I find one?
https://www.houzz.com/discussions/1503390/toro-suzuki-47p-engine-ignition-module-fix
Mike
Need an ignition coil for Toro 22035 walk behind
- Thread starter mxw1
- Start date
I just found this old post, has anybody ever heard of this before and can I try this Nova II module?
Where do I find one?
https://www.houzz.com/discussions/1503390/toro-suzuki-47p-engine-ignition-module-fix
Mike
bertsmobile1
Lawn Royalty
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- Nov 29, 2014
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The Nova II s a Hall Effect Trigger unit.
BAsically they are point eliminators.
They used the be a stand alone item connected to the coil.
But engine makers got greedy and put them inside the coil which now became an "ignition module" for 20 times the price of the coil & trigger units as descreet items.
I don't know if you can dig the old chip out of module and hook a Nova up to it but if yours is dead you have nothing to loose.
Novas and a few different Hall Effect Triggers are available from most mower shops
All of the aftermarket parts makes have one, Origon, Prime line, Stens, Rotary etc.
Some might even have several, one for 2 strokes & another for 4 strokes.
Atom Industries down here invented & marketed the units originally as the Atom Ignition Module and there were 7 of them each with different advance curves to suit different engines.
Every now & then some pop up when an old fart closes his shop and they dig down to the bottom of the obsolete parts bin.
Atom sold them from 1965 to 1996 when the patient ran out so every engine maker, made their own & they were no longer profitable.
They cost less than $ 1 to make but the rest of the original $ 20 went to packaging , distribution & retail profit, Atom wholesaled them for $ 5.
Some electronic geek shops have Hall Effect trigger kits which have programmable advance curves ( really a retard curve ) so you can try there as well.
The caveat is that Toro would have used its own distinctive advance so while your mower might run, the timing might be a little off
You will probably find the stand alone units at places that cater for old Lawn Boys, I think the OMC engines all used stand alone units.
If the unit has 1 terminal then you run a wire from the kill switch to the terminal & then to the coil
If it has 2 terminals and a metal body then kill wire to one & coil to the other
If it has 2 wires and a plastic body then it is ground to one & coil to the other
Rotary do Novas Item#8786
Stens do Mega Fire 440-465
Oregon don't have a name Part #33-053
Prime Line is Omega 7-01749
off Ebay https://www.ebay.com/itm/ELECTRONIC-IGNITION-MODULE-REPL-John-Deere-M70114-Kawasaki-21119-2095-9334-/222502818720
And how to build one yourself for $ 5, probably $ 7 now days
https://www.electro-tech-online.com/threads/atom-diy-module.142530/
Could almost guarantee they all come out of the same factory in China.
BAsically they are point eliminators.
They used the be a stand alone item connected to the coil.
But engine makers got greedy and put them inside the coil which now became an "ignition module" for 20 times the price of the coil & trigger units as descreet items.
I don't know if you can dig the old chip out of module and hook a Nova up to it but if yours is dead you have nothing to loose.
Novas and a few different Hall Effect Triggers are available from most mower shops
All of the aftermarket parts makes have one, Origon, Prime line, Stens, Rotary etc.
Some might even have several, one for 2 strokes & another for 4 strokes.
Atom Industries down here invented & marketed the units originally as the Atom Ignition Module and there were 7 of them each with different advance curves to suit different engines.
Every now & then some pop up when an old fart closes his shop and they dig down to the bottom of the obsolete parts bin.
Atom sold them from 1965 to 1996 when the patient ran out so every engine maker, made their own & they were no longer profitable.
They cost less than $ 1 to make but the rest of the original $ 20 went to packaging , distribution & retail profit, Atom wholesaled them for $ 5.
Some electronic geek shops have Hall Effect trigger kits which have programmable advance curves ( really a retard curve ) so you can try there as well.
The caveat is that Toro would have used its own distinctive advance so while your mower might run, the timing might be a little off
You will probably find the stand alone units at places that cater for old Lawn Boys, I think the OMC engines all used stand alone units.
If the unit has 1 terminal then you run a wire from the kill switch to the terminal & then to the coil
If it has 2 terminals and a metal body then kill wire to one & coil to the other
If it has 2 wires and a plastic body then it is ground to one & coil to the other
Rotary do Novas Item#8786
Stens do Mega Fire 440-465
Oregon don't have a name Part #33-053
Prime Line is Omega 7-01749
off Ebay https://www.ebay.com/itm/ELECTRONIC-IGNITION-MODULE-REPL-John-Deere-M70114-Kawasaki-21119-2095-9334-/222502818720
And how to build one yourself for $ 5, probably $ 7 now days
https://www.electro-tech-online.com/threads/atom-diy-module.142530/
Could almost guarantee they all come out of the same factory in China.
Last edited:
My tag is gone from the deck... the only number I have found is the number near the outside edge of the flywheel under the cooling shroud.
Thanks,
Mike
Very good info, I had no idea this was how it works.
I do have a question about this;
The "points" in a conventional type of ignition system are what triggers the timing of the spark, moving the ignition point location relative to the crank angle position in the cycle, is what changes the timing.
So with one of these imbedded transistors at the coil, I'm assuming that it is the "Crank Trigger" and it's position relative to the angle of the crankshaft position is important to the ignition timing. If I remove the original "transistor" and wire in a replacement module, doesn't it (the module) have to be placed in the same position on the coil to fire at the correct angle/ point in the cycle?
From what I'm understanding, you install the replacement module somewhere else and use an extension wire to connect it to the coil. How can it trigger properly if it's nowhere near the original location on the coil. The hall effect crank trigger must still be on the coil stack for this to work. Is the primary coil the "crank trigger" devise in a system like this, and the module is just the amplifier?
Thanks for listening,
Mike
bertsmobile1
Lawn Royalty
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You need to go back & read the article again.
The trigger is just that, a trigger for the coil to discharge into the plug
Just the same as a set of points is a trigger that allows the coil to discharge into the plug.
As such it matters not weather the trigger is on the coil, on the engine cover, on the steering wheel or on the rear fender.
All it does is go from open circuit to closed circuit at the right time.
A transistor is just a switch and it matters not where the switch is just so long as the switch switches.
In a set of points the cam opens which allows ( traps if you like ) the voltage being generated in the coil to rise then closes when the voltage is highest to allow that voltage to go to ground.
You change the timing by either moving the points with respect to the piston or changing the gap which does the same thing.
A coil passing a magnet does not instantly generate 10,000V.
It starts at 0V, rises to a peak voltage , say 10,000V then drops to - 10,000V before returning to 0 V
The hall effect simply measures the voltage being generated within the coil and when it gets to a certain voltage, the transistor closes = points closes and the coil fires.
In the stand alone device you have 3 transistors so a switch trips another switch which triggers another switch .
This is done because a transistor that is sensitative enough to switch at 5 micro volts would fry if it was subjected to the 10,000V primary voltage in the coil.
In fact it fries if exposed to the 12V of the battery.
How long it takes for all 3 transistors to close & thus the spark to happen is determined by the resistors which slow down the switching .
Read the entire forum thread on building an Atom if you are having trouble with this to see that the different timings were done by changing the value of the resistors.
By modern standards , the Atom circuit with indiividual parts soldered onto a board is a steam engine because now days the 3 transistors 4 resistors and diodes can all be made as a single silicon chip.
So the wire that comes out of the coil and grounds under one of the mounting bolts will go to the chip before it goes into the coil proper.
This wire can be 1/10" long or 100 inches long it really makes no difference.
All you are doing is removing the original chip ( if fitted ) and replacing it with the external hall unit .
External units generate heat, so they need to be in the airflow to get rid of the heat.
Silicon chips generate far less heat so sitting in the coil gets enough air flow to keep them cool.
The trigger is just that, a trigger for the coil to discharge into the plug
Just the same as a set of points is a trigger that allows the coil to discharge into the plug.
As such it matters not weather the trigger is on the coil, on the engine cover, on the steering wheel or on the rear fender.
All it does is go from open circuit to closed circuit at the right time.
A transistor is just a switch and it matters not where the switch is just so long as the switch switches.
In a set of points the cam opens which allows ( traps if you like ) the voltage being generated in the coil to rise then closes when the voltage is highest to allow that voltage to go to ground.
You change the timing by either moving the points with respect to the piston or changing the gap which does the same thing.
A coil passing a magnet does not instantly generate 10,000V.
It starts at 0V, rises to a peak voltage , say 10,000V then drops to - 10,000V before returning to 0 V
The hall effect simply measures the voltage being generated within the coil and when it gets to a certain voltage, the transistor closes = points closes and the coil fires.
In the stand alone device you have 3 transistors so a switch trips another switch which triggers another switch .
This is done because a transistor that is sensitative enough to switch at 5 micro volts would fry if it was subjected to the 10,000V primary voltage in the coil.
In fact it fries if exposed to the 12V of the battery.
How long it takes for all 3 transistors to close & thus the spark to happen is determined by the resistors which slow down the switching .
Read the entire forum thread on building an Atom if you are having trouble with this to see that the different timings were done by changing the value of the resistors.
By modern standards , the Atom circuit with indiividual parts soldered onto a board is a steam engine because now days the 3 transistors 4 resistors and diodes can all be made as a single silicon chip.
So the wire that comes out of the coil and grounds under one of the mounting bolts will go to the chip before it goes into the coil proper.
This wire can be 1/10" long or 100 inches long it really makes no difference.
All you are doing is removing the original chip ( if fitted ) and replacing it with the external hall unit .
External units generate heat, so they need to be in the airflow to get rid of the heat.
Silicon chips generate far less heat so sitting in the coil gets enough air flow to keep them cool.
I did buy a used coil on e-bay for about $50. It is a little different than mine; it doesn't have an additional ground lead like mine did.
I installed it and it works fine, until you shut it off, if you try to re-start it while it's hot, there is no spark, just like my original does.
I'm keeping it anyway, I will use it until it fails, then I'll have another to last a few more years.
I guess I can try one more thing; I could spray some aerosol "Freeze Spray" while it's hot and not producing a spark and see if it starts...
Thanks to everyone that contributed, it was very beneficial.
Mike
I installed it and it works fine, until you shut it off, if you try to re-start it while it's hot, there is no spark, just like my original does.
I'm keeping it anyway, I will use it until it fails, then I'll have another to last a few more years.
I guess I can try one more thing; I could spray some aerosol "Freeze Spray" while it's hot and not producing a spark and see if it starts...
Thanks to everyone that contributed, it was very beneficial.
Mike
mechanic mark
Lawn Pro
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