And which flywheel did you use? There are at least three: one for points, one for the SEM electronic and one for the Bosch electronic?
Stihl 041 Super AVE - No Spark - SEM Electronic Ignition
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bell222jetranger
ArboristSite Lurker
bell222jetranger
ArboristSite Lurker
its also to referred to as timing / before or After top dead center of the piston.
bell222jetranger
ArboristSite Lurker
i have (2) 041 saws one was a bosch electronic ign / and the other was SEM electronic ign/ The Bosch module i replaced with the bosch module with one from Ebay the one i posted the SEM module i cut it off the backing timing/plate and installed a Nova ll electronic module with new coil and all is well Both run great again. My old SEM model is dated 1963.
scruffy808
ArboristSite Lurker
I had similar trouble with a 1983 Stihl 031 chainsaw. Ignition coil weak (as tested by Stihl Dealer)"with poor spark or none at pull over speed so got to point where impossible to start. No genuine parts available so procured aftermarket finally, but its armature mounting holes in wrong place. In desperation took new coil off and fitted it to old armature. Good spark now saw would start up BUT performed poorly lack of power backfiring thru carby, and not able to be tuned by carby screws. Turns out ignition timing was badly retarded sparking well after TDC. Ended up removing flywheel woodruff key and advancing flywheel on crankshaft. Guess "coils aint coils" as this import coil had a different characteristic somehow. Good luck finding ignition coils for older models.
I have a bosch coil and 2 piece flywheel along with the capacitor for the foggysail fix. It came off a 056 mag 2. I switched it over to the sem coil and flywheel. The sem coil is still available new from stihl. I could part ways ith the bosch set up.
There is an equivalent product available on the US eBay site by "Proline"
Proline® Ignition Coil For Stihl 041 045 056 Replaces Original Bosch Ducati
https://www.ebay.com/itm/224967968959?hash=item346122c8bf:g:Tf0AAOSwCYRifalO
While the advert states it is only for the Bosch Ducati type of electronic ignition, I suspect it could be used with an SEM flywheel, but one would have to rotate the SEM flywheel on the crankshaft to get the timing correct.
scruffy808
ArboristSite Lurker
Your request was long ago but if you still have problems......I got an aftermarket coil for an 031 Stihl around 1983 vintage, in Australia, but it did not fit despite supplier saying it was for that model saw. Saw was originally running points. Problem was the bolt hole spacing in the laminated coil armature was wrong. As you say even in USA land of plenty ignition coils are scarce.!!
Not to be defeated I took new coil off its core and fitted it to old core so it bolted on no trouble. The HT lead was also facing wrong way but bit of housing grinding and re routing fixed that.
Next saw would start BUT ran terrible - carby backfiring, no power, no or little response to carby tuning, only thing different was the new coil!!
Turns out ignition timing now badly retarded all due new coil!! This saw runs an NLA Atom electronic ignition module see photo. Cannot say if coil I got in Australia would fit an 041 but surely someone out there has them in USA. if we can get one here!! I fixed my problem by changing timing , see my first ever thread titled "Stihl saws kickback on starting". Hope this helps mate!!
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Scruffy, thanks for writing what you did. I was able to buy an 041 Farm Boss parts saw off of eBay. It had the SEM electronic ignition system, so I installed that and now my old 041 super runs like it used to. Along the way, I picked up an 041 points stator and flywheel, so I can install those, if need be. I also picked up an 041 Bosch ignition module and the correct flywheel for that style of ignition, so I've got options in case my SEM unit goes bad. The parts saw was actually in pristine condition with no damage to the piston or bore, so I will make that saw come alive again. I bought a 500i Stihl at Christmas and an MS201T last October, so really I have plenty of chainsaws to use. I just didn't want to throwaway that old 041 Super because I've had it since 1988 and it had been one of the most reliable saws I'd ever owned. Till the SEM ignition module died. But all good now.
John
John
Hi guys and cheers from Croatia. 
I have recently moved to my late grandfather's old (very old, built in 1724) house on village. I've lived 50 years in a city, and I love it here.
I have a small olive grove (34 olives), small garden around house, I heat my house with wood, so a lot of tree felling and stuff going on.
Found this forum through google, and I see there are some good and knowledgeable people here.
Here's my problem, if anyone can help, it would be greatly appreciated.
I inherited an old Stihl 041 AV electronic from my late grandfather, bought somewhere in 70s in Germany by my late father.
I have a Stihl MS 251 which is a fine chainsaw, but I have tried to revamp this old beast to be a replacement/second saw.
Cleaned her, rebuilt the carburetor (all membranes and stuff), the spark was there, compression is there, but no luck in starting it. Then I saw that the ignition switch cable was stripped bare of insulation, tried to insulate it, but still no luck.
Then I went to Stihl service and left the chainsaw there to see if they can do anything.
Their diagnosis is that the ignition module is not functioning properly and has to be replaced. And that it is worth it, because all other parts and functioning are ok.
So I've found that saegenspezi guy with the replacement module, as I've also found in this thread.
My main concern is that the mounting holes are not in the same position.
I have attached the comparison picture where the difference can be clearly seen.
Can this prevent the ignition timing to be correctly set or is it irrelevant, i.e. the flywheel/magneto can be accordingly positioned?
Thanks in advance.
I have recently moved to my late grandfather's old (very old, built in 1724) house on village. I've lived 50 years in a city, and I love it here.
I have a small olive grove (34 olives), small garden around house, I heat my house with wood, so a lot of tree felling and stuff going on.
Found this forum through google, and I see there are some good and knowledgeable people here.
Here's my problem, if anyone can help, it would be greatly appreciated.
I inherited an old Stihl 041 AV electronic from my late grandfather, bought somewhere in 70s in Germany by my late father.
I have a Stihl MS 251 which is a fine chainsaw, but I have tried to revamp this old beast to be a replacement/second saw.
Cleaned her, rebuilt the carburetor (all membranes and stuff), the spark was there, compression is there, but no luck in starting it. Then I saw that the ignition switch cable was stripped bare of insulation, tried to insulate it, but still no luck.
Then I went to Stihl service and left the chainsaw there to see if they can do anything.
Their diagnosis is that the ignition module is not functioning properly and has to be replaced. And that it is worth it, because all other parts and functioning are ok.
So I've found that saegenspezi guy with the replacement module, as I've also found in this thread.
My main concern is that the mounting holes are not in the same position.
I have attached the comparison picture where the difference can be clearly seen.
Can this prevent the ignition timing to be correctly set or is it irrelevant, i.e. the flywheel/magneto can be accordingly positioned?
Thanks in advance.
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Welcome to the Forum! Hello from Washington State in the USA.
Per this thread https://www.arboristsite.com/threads/need-056-super-repair-in-ga.345820/page-2#post-7381871
"Uses your existing Bosch flywheel. Not very hard to install, just need two new (longer) mounting screws & a 4mm/0.156” metric female bullet terminal for your kill wire end. Sometimes you may have to belt sand their stator plate’s outside diameter down to get it to fit...but timing & spark is spot on."
The Saegenspezi ignition unit will work correctly with a Bosch electronic flywheel, without any timing adjustments required.
Your Bosch ignition module may be repaired if the cause is a bad capacitor in its charging circuit by following the instructions in this thread by user Foggysail:
https://www.arboristsite.com/thread...ihl-045-056-bosch-electronic-ignition.256095/
Good luck!
John
Per this thread https://www.arboristsite.com/threads/need-056-super-repair-in-ga.345820/page-2#post-7381871
"Uses your existing Bosch flywheel. Not very hard to install, just need two new (longer) mounting screws & a 4mm/0.156” metric female bullet terminal for your kill wire end. Sometimes you may have to belt sand their stator plate’s outside diameter down to get it to fit...but timing & spark is spot on."
The Saegenspezi ignition unit will work correctly with a Bosch electronic flywheel, without any timing adjustments required.
Your Bosch ignition module may be repaired if the cause is a bad capacitor in its charging circuit by following the instructions in this thread by user Foggysail:
https://www.arboristsite.com/thread...ihl-045-056-bosch-electronic-ignition.256095/
Good luck!
John
Thanks for the quick reply.
Yeah, I saw that Foggysail's fix, but:
a) How can I test that the capacitor is the problem here?
b) If you look at my module, there are two wires coming from the coil to the black epoxy thingy. On Foggysail's picture there aren't any, so
, not sure if applicable here. I have some basic soldering skills, but first I'd like to be sure that it's the capacitor.
Thanks for the first URL, which inspires trust in that sagenspezi product.
We'll see...but I'm happy that there are possible solutions out there, my granddad would be glad to see it working again.
Yeah, I saw that Foggysail's fix, but:
a) How can I test that the capacitor is the problem here?
b) If you look at my module, there are two wires coming from the coil to the black epoxy thingy. On Foggysail's picture there aren't any, so
, not sure if applicable here. I have some basic soldering skills, but first I'd like to be sure that it's the capacitor.Thanks for the first URL, which inspires trust in that sagenspezi product.
We'll see...but I'm happy that there are possible solutions out there, my granddad would be glad to see it working again.
Attached is a picture of a Bosch CDI ignition stator plate I have. On the lower half of the plate you can see a white insulated wire going from the black epoxy to the left side of the ignition induction coil. On the right side of the induction coil is a black wire coming out of the coil and going into the expoxy. You can see a bare multi-stranded wired coming out of the expoxy, right next to the black wire. The bare copper wire is missing its insulation; it is the wire that goes to the kill switch used to shut off the engine.
I have uploaded a picture from Foggysail's thread (from page 3 of that thread) that shows his Bosch Stator which he modifies. He has applied some form of orange silicone rubber or sealer in an effort to prevent the wires from moving due to vibration and grounding out. At least I think that is what he did. My point is that his stator plate actually has the same wires as mine; they were just colored/covered up wth orange sealer.
If you read through Foggysail's thread he explains what went wrong and how he fixed it by replacing the built-in capacitor which is under the expoxy with an externally mounted capacitor which keeps the new capacitor in a cooler part of the saw, so it is less likely to fail.
To answer your part a) question: How to test if the ignition inductance circuit capacitor is bad: There really isn't an easy way because it is covered up by the black epoxy. Foggysail is an electrical engineer and understands electronic circuitry extremely well. He deduced by looking at the circuit (it is described and pictured in a Stihl 041 shop manual). And he figured out that it was the most likely component to fail due to heat because of his experience in the electronics field.
Reading the various threads on the forum about failed 041 electronic ignition systems, it seems like the most common culprit is the inductance circuit capacitor that Foggysail has figured out how to effect a repair.
The SEM brand CDI ignition systems likely fail in a similar way, but they are potted with a very high temperature and very hard epoxy which cannot be easily removed to get to the underlying circuitry, as can be done with the Bosch system.
I've included a picture of the SEM CDI ignition stator for comparison. My understanding is that the circutry inside the SEM unit is very similar as in the Bosch unit. The inductance coil in the SEM is contained within the black expoxy, on the lower half of the stator plate, similar to where they are located on the Bosch unit, just where the Bosch inductance coil is located.
I think you could probably repair your Bosch ignition using Foggysail's method; the capacitor needed is considerably less expensive than the Saegenspezi solution. But The Saegenspezi solution is proven to work as well.
John
I have uploaded a picture from Foggysail's thread (from page 3 of that thread) that shows his Bosch Stator which he modifies. He has applied some form of orange silicone rubber or sealer in an effort to prevent the wires from moving due to vibration and grounding out. At least I think that is what he did. My point is that his stator plate actually has the same wires as mine; they were just colored/covered up wth orange sealer.
If you read through Foggysail's thread he explains what went wrong and how he fixed it by replacing the built-in capacitor which is under the expoxy with an externally mounted capacitor which keeps the new capacitor in a cooler part of the saw, so it is less likely to fail.
To answer your part a) question: How to test if the ignition inductance circuit capacitor is bad: There really isn't an easy way because it is covered up by the black epoxy. Foggysail is an electrical engineer and understands electronic circuitry extremely well. He deduced by looking at the circuit (it is described and pictured in a Stihl 041 shop manual). And he figured out that it was the most likely component to fail due to heat because of his experience in the electronics field.
Reading the various threads on the forum about failed 041 electronic ignition systems, it seems like the most common culprit is the inductance circuit capacitor that Foggysail has figured out how to effect a repair.
The SEM brand CDI ignition systems likely fail in a similar way, but they are potted with a very high temperature and very hard epoxy which cannot be easily removed to get to the underlying circuitry, as can be done with the Bosch system.
I've included a picture of the SEM CDI ignition stator for comparison. My understanding is that the circutry inside the SEM unit is very similar as in the Bosch unit. The inductance coil in the SEM is contained within the black expoxy, on the lower half of the stator plate, similar to where they are located on the Bosch unit, just where the Bosch inductance coil is located.
I think you could probably repair your Bosch ignition using Foggysail's method; the capacitor needed is considerably less expensive than the Saegenspezi solution. But The Saegenspezi solution is proven to work as well.
John
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Tduic, one other thing you might check before you replace the Bosch stator with the Saegenspezi solution or begin modifying the Bosch ignition per Foggysail's method, would be to to check that the black wire that runs to the kill switch, isn't grounding out anywhere between the ignition module and the switch. I have read threads about certain years of Stihl saws that were assembled with wires that had "green" insulation, meaning enviromentally friendly, but the insulation did not hold up and would fail prematurely compared to the older type of insulation. If that wire shorts to ground, the engine won't start.
John
John
Tduic, there is another thread which details Foggysails fix installed on an 045/056 Stihl saw with Bosch electronic ignition system. Same ignition unit as on our 041's.
Good pictures and details are shown in the Thread:
https://www.arboristsite.com/thread...-056-bosch-electronic-ignition.256095/page-41
The correct external capacitor needed can be bought in the UK from: https://au.element14.com/kemet/r75m...p/2456384?st=pulse 1uf 400v mkp capacitors uk
Good pictures and details are shown in the Thread:
https://www.arboristsite.com/thread...-056-bosch-electronic-ignition.256095/page-41
The correct external capacitor needed can be bought in the UK from: https://au.element14.com/kemet/r75m...p/2456384?st=pulse 1uf 400v mkp capacitors uk
Killswitch wire was definitely stripped (see the pic of it coming out from the flywheel case near the impulse line connector), before it went to the Stihl service. They replaced the wire, also put a heatshrink over one part of the spark plug wire. Only after fixing this they've come to the conclusion that the ignition module is kaputt (german word for broken/fubar).
(I'm relatively ok with german technical language so in case someone needs an amateur translation, I can help).Attachments
@vision976 Huh, it seems my module is slightly different than yours and FoggySails'. Check out this comparison I've made. From left to right: FoggySails, yours, and mine. First two are identical, but see mine, which has another component (that orange/yellow thingy) on top of the ignition coil. My ignition coil is part number 2 204 211 (112) in difference to other two, 2 204 211 (040). So exactly at the place where I should melt the epoxy there are two wires, which both of you don't have. That's why I'm not sure whether I should try it or not. The killswitch wire comes out from the opposite side of the stator plate from the right side wire outlet of that yellow thingy, not from the place where it comes from your modules (see pic).
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You are correct, Tduic, your stator is a different model and part number than the one FoggySail modified and that I have. Mine has a part number of 2 207 031 148; yours is 2 207 031 126. I suspect yours is an earlier version since the last three digits of the part number are lower.
I've included some screen snips from a scanned version of a Stihl 041 Shop Manual that explains how the Bosch and SEM electronic Ignition CDI systems work. Note that in the diagrams, the inductance coil that charges the capacitor is at the top of the picture and the high voltage coil that creates the spark is at the bottom. Sorry for the poor image quality, but that's the way the manual came to me.
The 5th image is a large one with 3 red arrows indicating the 3 wires that come up out of the epoxy and go to the high voltage ignition coil as your stator has. In fact, the outline of the metal "can" into which the potted epoxy has been filled, shows it to be the same exact shape as what your stator has. I put yellow arrows pointing out the curved shapes of the metal can to make it clearer that the image represents the stator you have.
Per the circuit diagram, those two wires that attach to the right side of the high voltage coil (in the diagram) are in fact tied together on the circuit board, under the epoxy. And they are attached to one side of the charging capacitor per the diagram.
While I can't be absolutely certain, I think if you remove the epoxy from the side of the epoxy filled "can" where the two side-by-side wires exit the epoxy, you'll be in the area that needs to have the circuit cut to the bad capacitor and a new wire soldered per FoggySail's fix.
You don't have much to lose, since the unit is not functioning properly now, just be careful removing the epoxy. Worst case if you botch the job, you can always install the Saegenspezi module. I have read in threads on this forum, that the Saegenspezi solution may fail due to heat after a time. But the Saegenspezi module has been on the market for a long time. There are other ignition "chip" solutions by "Atom" and other vendors, which can be mounted in locations not under the flywheel (similar to how Foggysail's capacitor fix it out from under the hot flywheel environment)
I've included two images from the long 045/056 thread uploaded by "Deleted User"; he removed the epoxy potting entirely from a Bosch ignition system and actually removed the printed circuit board in an effort to replace the bad capacitor, but could not find a new one that would fit in the space the old one was located.
When you get the epoxy out of the area of the capacitor, you should be able to see the printed circuit board conductor path which needs to be cut and have the wire soldered to.
Good luck!
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Thank you so much man, this pretty much explains it all. .png "Love :heart:")
So looking at the schema, it seems this orange wrapped thing is the primary winding of the ignition coil. Weird that the coils are not intertwined for stronger transfer of magnetic flux.
The capacitor is then obviously on the right side of the can and there I'll try to remove the epoxy.
Now in the hunt for capacitor, the link you gave me doesn't ship to Croatia, but I'll try to contact them or find a suitable alternative in my country or something. Yeah, as you say, nothing to lose. And I'm not in any sort of hurry, so let's play a little, and I always have sagenspezi as a last resort.
I'll inform you of any updates.
So looking at the schema, it seems this orange wrapped thing is the primary winding of the ignition coil. Weird that the coils are not intertwined for stronger transfer of magnetic flux.
The capacitor is then obviously on the right side of the can and there I'll try to remove the epoxy.
Now in the hunt for capacitor, the link you gave me doesn't ship to Croatia, but I'll try to contact them or find a suitable alternative in my country or something. Yeah, as you say, nothing to lose. And I'm not in any sort of hurry, so let's play a little, and I always have sagenspezi as a last resort.
I'll inform you of any updates.
Well, I removed epoxy with heat gun, and now I'm a little bit stuck/not sure where and what to do. Analysing the board and looking at the schema, I think this is the situation, and my proposed locations for cutting of the circuit and soldering the wire. Am I right? BTW, the other wire of the capacitor should be soldered to the ground, anywhere I can find it, is that right or?
