testing ignition module

[rickwil]

I agree with SteveSr: The newer coils have a PIC microprocessor in them...(and lots of other stuff now days use solid state devices buried inside and sealed)

Not much learned here for me. (and I've seen the old style ignition system coils several times test ok using a test meter and ignition coil/Magneto tester and not work correctly on the equipment.) (weak or erratic usually) I've got all kinds of electronic test eq, coil testers, Magneto testers, condenser testers, and real world test when all is said and done is too sub with a know good part and quit farten around.
When I find something bad/intermittent/erratic especially electronic ignition module systems for instance I replace it or sub with know good one and quit FARTING around wasting time.
and I'm a electronic tech, electrician, mechanic.

I have been having problems with a Stihl BR600, no spark. I have tried several coils. I made a jig out of an old magneto and crankshaft that will spin the magnetic flywheel close to a properly gapped coil. All of the tested coils (2 new, 1 old) will not produce spark until about 300 rpm. which makes the blower impossible to stat by hand or run at low speeds. Do you know the possible reason? I am quite familiar with electronics, electrician, power engineer, and hd mechanic (retired) but this has me stumped.

 

[purdyite]

Had a saw that wouldn't start--tested with the neon spark tester and spark seemed fine. HOWEVER--after some examination, I found that the porcelain sleeve around the electrode on the plug was broken at the base and was shorting the plug--it fooled the spark tester. I turned the plug upside down and noticed that the gap had disappeared! The porcelain sleeve had slid down to the gap. Shaking the plug, I heard a clicking sound as the sleeve was moving back and forth. Pretty sure spark plugs shouldn't make noise when you shake 'em.

 

[rickwil]

Had a saw that wouldn't start--tested with the neon spark tester and spark seemed fine. HOWEVER--after some examination, I found that the porcelain sleeve around the electrode on the plug was broken at the base and was shorting the plug--it fooled the spark tester. I turned the plug upside down and noticed that the gap had disappeared! The porcelain sleeve had slid down to the gap. Shaking the plug, I heard a clicking sound as the sleeve was moving back and forth. Pretty sure spark plugs shouldn't make noise when you shake 'em.

I tried with new spark plugs still the same. I'll try to give the engine the fastest pull that I can, I guess.

 

[a. palmer jr.]

I usually don't have any problem testing the Stihl modules, I just replace them with a known good one. With other brands it's not so easy to do...

 

[rickwil]

I usually don't have any problem testing the Stihl modules, I just replace them with a known good one. With other brands it's not so easy to do...

Problem is that I have tried 2 new ones (Chinese made) but in the past have not had problems with the Chinese ones in other blowers.

 

[a. palmer jr.]

Yeah, I usually just work on chainsaws but I know that not all the new ones are good but is it possible something is wrong with the flywheel? Sometimes when you shear the key it will still have spark but it will be at the wrong time.

 

[cscltd]

I have been having problems with a Stihl BR600, no spark. I have tried several coils. I made a jig out of an old magneto and crankshaft that will spin the magnetic flywheel close to a properly gapped coil. All of the tested coils (2 new, 1 old) will not produce spark until about 300 rpm. which makes the blower impossible to stat by hand or run at low speeds. Do you know the possible reason? I am quite familiar with electronics, electrician, power engineer, and hd mechanic (retired) but this has me stumped.

Most modern electronic modules will not light up at 300rpm, in fact no small engine will run at 300rpm, even your “HD engine” idles over 300rpm i think , br600 idles around 2800 rpm, thus if you get spark at 300rpm and no start, you may have another issue or an non Oem module not working correctly

 

[KASH]

Pioneer 600 in good tune will idle at 450 rpm all day long.I watched several shows on testing old outboard motors lots of these idle at 300 no problem.I thought that ignition problems were a thing of the past when electronic ignition came out.It turns out if your saw gets to be a few years old it"s pretty well assured your piece of junk coil will fail and your SOL because it is NLA.
The beauty of points file them many a couple of times during the 2000 or so hour life time of the chain saw.
When you check for spark with points you just turn the crank with your hand hand and watch and hear that healthy bright blue spark jump the 3/16 gap to ground.
Kash

 

[Old2stroke]

I have been having problems with a Stihl BR600, no spark. I have tried several coils. I made a jig out of an old magneto and crankshaft that will spin the magnetic flywheel close to a properly gapped coil. All of the tested coils (2 new, 1 old) will not produce spark until about 300 rpm. which makes the blower impossible to stat by hand or run at low speeds. Do you know the possible reason? I am quite familiar with electronics, electrician, power engineer, and hd mechanic (retired) but this has me stumped.

For every ignition module there is a minimum velocity of the magnets sweeping past the coil pieces that will induce enough energy in the primary to allow the circuitry to work.

 

[Old2stroke]

We are constantly getting questions about testing coils with an ohm meter and, as stated above, due to the electronic package that switches the primary, there is NO relevant test you can perform that will determine if the coil is faulty or not. The coil is an auto transformer and that means that the primary and secondary both have the same ground (connected internally to the coil legs) and it MUST be securely connected to the cylinder, so the only good test you can do with an ohm meter is verify this connection and you can do this by measuring the resistance between the plug end of the high tension lead and the cylinder. It should be the value of the secondary ( about 5 Kohms), if it is a lot higher it could be a bad connection at the end of the lead or high resistance between the coil legs and its mounts.

 

[rickwil]

Most modern electronic modules will not light up at 300rpm, in fact no small engine will run at 300rpm, even your “HD engine” idles over 300rpm i think , br600 idles around 2800 rpm, thus if you get spark at 300rpm and no start, you may have another issue or an non Oem module not working correctly

It may be the Chinese module that I installed. Not sure about the actual RPMs I was spinning it, just a guess but it seemed fairly fast. Give it another go today.