No Spark on Boyer - Fixed

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Negative Ground. Boyer MkIII new (been sitting in box for years). Bike ran but was hard to start (now seems to be because of intermittent spark?)
No Spark on Boyer - Fixed


NO SPARK CHECK:

BATTERY HAS POWER?: Switch on headlamp and activate stop lamp. They should stay bright for more than one minute.
12.9v at battery.

THE FUSE KEEPS BLOWING: Replace the fuse with a 21 watt indicator bulb. As the individual electrical circuits are switched on, the bulb will glow dimly, if a faulty circuit is connected, the bulb will glow brightly. If the bulb glows brightly with nothing switched on, remove wires from components in turn until the bulb goes out; the last one removed will be the faulty circuit.
No apparent fuse problem.

IGNITION UNIT HAS POWER?: Using a bulb or voltmeter check the main power feed to the ignition unit. This would be the wire from the ignition or kill switch. With bulb connected between the ignition feed wire at the ignition box and battery ground, the bulb should glow brightly. If dim or varying, try moving the fuse holder, wiring, handlebars, to locate any faulty connection.

Then test between the ignition feed wire at the box and the wire used to ground or earth the ignition system. If the bulb glowed brightly when connected between the feed wire and battery ground system, but is dim when connected between the ignition feed wire and the wire used to ground the ignition, you have a faulty ground. (The bulb draws similar current to the ignition and is a more useful test than the voltmeter only.) Poor earth connections are hard to locate.
Appears good.

THE UNIT HAS POWER – SPARKS ON SWITCHING ON AND OFF: Most early MKIII (not Micro-MKIII, Micro-Digital or Micro-Power which will not spark when turned on and off) ignition units will produce a spark on switching on and off; if this is so and sparks are produced on all cylinders then the ignition coils must be in good order. If one or more fail to spark, a coil could be faulty. On four cylinder machines try disconnecting one coil at a time, and switching on and off, checking for sparks. On other machines that use more than one coil in series one coil failing can stop sparking due to coil failure and cause all the coils not to spark.. Also one coil can have an internal short to ground, and while it will fire, it can cause the coils after it in the chain (which are in good working order) to stop working. This is very common when a Lucas/PVL coils that are over tightened in the metal clamp. The case becomes crushed and touches the windings inside. This can occur when the coil warms up. The Micro-MKIII, Micro-Digital and Micro-Power units all turn off when not being triggered, therefore, it is best to carry out the next test as you may not always have a spark on turning on and off.
Using a timing light there is no spark when turning ignition on and off. Will check at spark plug.

THE UNIT HAS POWER – NO SPARKS ON SWITCHING ON AND OFF AND NO SPARKS WHEN CRANKING: After performing the bulb test above to ensure the box has power, disconnect the wires from the ignition box that go to the pickup trigger plate. With the ignition on, touch these two wires together. Making and breaking the connection should make a spark at the spark plugs. If no spark is present then the ignition box is most likely (see checking coils above) faulty. The only units that will not trigger in this way are the racing crank triggered Digital and Norton rotary units (A rapid tap on the end of the pickup will induce the ignition to fire. A single tap will arm the ignition, but if it does not see additional signals after a few seconds will turn off the box and inadvertently fire the coil). Check that the rotor magnets are running within the two metal pole pieces on the trigger plate. On British machines it is possible to move the rotor out slightly by placing a thin metal shim around the taper. The ignition will not fire by hand at less than 200 rpm.
Appears to spark when MAKING not BREAKING contact with the two stator wires.

Will fire when pushing then releasing kill switch.

CHECKING THE PICKUP PLATE: A full visual check of the condition of the circuit board and coils looking for loose or broken parts. Check for signs of the rotor touching the solder connections. Using a multimeter check the resistance of each pickup coil (should be approx. 65 ohms or 130 ohms across the two coils) and the total resistance across the wires or terminals. With the meter still attached, run your fingers around the coils, if the resistance changes there could be a broken winding inside. Attach the meter across the trigger plate’s wires and pull on them. If the resistance changes you could have a broken wire.
All circuits check out.

CHECKING THE ROTOR: The magnets on the Boyer ignition rotor should just hold the weight of the rotor when placed against a piece of steel. Check the marking spots are the same way around. All magnets should have a similar amount of strength.
Did not check

SPARKS ON CRANKING BUT WON’T FIRE: Check the pickup wires do not change colour in the wiring loom, as swapping these will make the ignition fire over 50 degrees retarded. With the digital system, check that you have suppressed plug caps fitted of approx. 5,000 ohm. If timing has just been done, don ‘t forget that the timing angle on the camshaft is half of the crankshaft’s (i.e. on a 650 Triumph full advance timing is 38 degrees but is set at 19 degrees on the camshaft.)
Won't fire on crank.

CONTINUOUS SPARKING WITHOUT CRANKING THE ENGINE: A poor battery with a battery charger connected or one or more bad cells in the battery. A high resistance in the wiring circuit or earth return. Check that the engine is earthed back to the frame and battery circuit. Plastic (powder coated) frames must have a good earth connection to the engine case and battery. A wrong type of ignition coil with a very low primary resistance (under 2 to 3 ohms) will draw a very high current and produce a large volt drop across the wiring. All these will keep turning the ignition on and off, generating a chain of sparks.
No
 
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Re: No Spark on Boyer

check your plug caps! I had one go bad recently, and it stopped the bike dead. It would give one spark when switched on, but that was it. New cap cured it, check that they have the right resistance with a multimeter.
 
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Re: No Spark on Boyer

Seeley920 said:
check your plug caps! I had one go bad recently, and it stopped the bike dead. It would give one spark when switched on, but that was it. New cap cured it, check that they have the right resistance with a multimeter.

Brand new from Old Britts.

No resistor caps, no resistor wires. Wires measure approx 1 ohm resistance. Thinking about trying resistor plugs next.
 
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Re: No Spark on Boyer

I notice the wire diagram shows Negative-Ground instead of factory Positive-Earth.
I assume you carried that through consistent with the Boyer supply.
Order of the black or yellow trigger wires the mag coil passes first matters on this too. Most common thing I've had give one spark on testing then nothing on real starting attempt was bad connection somewhere.
 
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Re: No Spark on Boyer

hobot said:
I notice the wire diagram shows Negative-Ground instead of factory Positive-Earth.
I assume you carried that through consistent with the Boyer supply.
Whole bike is negative ground if that is what you mean.

hobot said:
Order of the black or yellow trigger wires the mag coil passes first matters on this too.
What do you mean by this?

hobot said:
Most common thing I've had give one spark on testing then nothing on real starting attempt was bad connection somewhere.
This is also a very good suspect. I'm starting to doubt my whole wiring harness.
 
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Re: No Spark on Boyer

Ok then consistent in wiring paths of - & + supply in and back to battery.

Hidden breakage prone B/w B/y trigger leads are easy to switch places on the trigger plate. Even that would spark consistently though, just not on good time.

May end up like me, taking on project that's always just a bit ahead of what I can keep up with in fault finding and fixing. Crashing don't count in your case, yet.

As you have gone through and checked off the Boyer exam, might imply Boyer itself.
Get high, get relaxed and go step by step wire by wire, component by component, once more, then beg barrow another Boyer to slip in and see if changes anything.
I may even have a left over analog black box I'm so done with but functional.
 
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Re: No Spark on Boyer

CanukNortonNut said:

If you guys could stand watching that video until the end you saw the bike start and run. So, I believe everything is wired correctly. In theory. Now it just comes down to troubleshooting.

The two weird aspects are:

1. Boyer will not fire when ignition is switched on or off. Correction, if I do 2 (below) it will fire when I turn it off, this should be normal-ish.
2. If you turn the ignition on and hit the kill switch more than once it will spark. It will not spark on the first push but it will on the second or third. Consistently.

It will not spark when kicking over.
 
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Re: No Spark on Boyer

Dunno, but I'd sure try swapping out with another Boyer if you have one. I know it's new, but it seems similar to a problem I had once with intermittent spark. It was the box.
 
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Re: No Spark on Boyer

Aw sheeze, never heard of resistor plug caps failing resistively just split and short out side of chamber.
What was it Sherlock Homes said about process of elimination leading to the next to impossible to consider.
Your kicking marathon gain a rather rough sounding running but assumed that was d/t you reporting finding it 40' advanced at the time. Hmm, to do that requires messing with the trigger plate, hm.
Great sit com, quiz show, make over reality show, going eh for vintage gear heads.
 
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Re: No Spark on Boyer

I think I'll try the resistor plugs first (always replace the least expensive parts first). See if that makes any difference.

From what I can tell on the Norton the Boyer will not fire when the ignition is switched on, just when it's switched off.

I have another Boyer, unfortunately it's for a Triumph.

Anyone know a test for the Dyna coil? I'll as Fred too.
 
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Re: No Spark on Boyer

hobot said:
Your kicking marathon gain a rather rough sounding running but assumed that was d/t you reporting finding it 40' advanced at the time. Hmm, to do that requires messing with the trigger plate, hm.

Static was 31º, as best we could tell at 5k it was 40º. Which is within the range I've heard is possible. The smooth garage floor made it really challenging to hold it at 5k. It scooted back so fast even with me doing my best to corral it. I should have dropped it off the center stand.

On one of the attempts I got it to idle about 1k so the rough sound probably had more to do with the starting settings on the carbs.
 
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Re: No Spark on Boyer

swooshdave said:
hobot said:
Static was 31º, as best we could tell at 5k it was 40º. Which is within the range I've heard is possible. The smooth garage floor made it really challenging to hold it at 5k. It scooted back so fast even with me doing my best to corral it. I should have dropped it off the center stand.

What???,31* should be your max,set the simple stuff up correct before fiddling with other crap.

Were the hell is the degree symbol on this bloody computer????
 
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Re: No Spark on Boyer

If you are using Windows it's in Accessories/Character Map. As in 31°.
 

maylar

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Re: No Spark on Boyer

Try bypassing the kill switch just for grins. They are notoriously unreliable if it's the stock Lucas switch on the throttle cluster.
 

RoadScholar

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Re: No Spark on Boyer

Boyers' like 5K resistor caps, so the instruction say; they cut down the electro magnetic radiation field, which can kill the black box.

RS
 
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Re: No Spark on Boyer

I recently lost the spark completely on the left side, cure was an extra earth lead from the head to the frame where the boyer earth was and a further earth from there back to the battery.
 

batrider

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Re: No Spark on Boyer

Nope. Only the digital Boyers call for 5K resistance (either wires or plugs but not both). Analog Boyer should be OK just straight wire.

Russ
 
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