Stihl 041 AV Bosch Electronic Ignition Module

[randyw]

Hello,
I'am trying to learn more about the electronic ignition module on my 041.
I have attached a picture of the ignition with labels (A,B,C) and I am trying to determine what each part is? My saw had spark but no fire. Can anyone help me determine which part I need to replace? Maybe a lead on where to find the part? :help:
TIA,
-rw

 

[Fish]

Spark but no fire?

Where did you get that pic? The 041 had a lot of variations, but that one does not look familiar.

 

[randyw]

My bad on the lingo "spark but no fire". I guess what I mean is I had great spark at the plug but the saw would not "fire" up.
I took the picture of the ignition after I removed it from my saw. What I was curious about is do I need to replace the whole thing or just a part (A,B,C)? Thanks for the reply Fish.
-rw

 

[Fish]

Well, if you had great spark, then your problem likely is elsewhere.
Go back and start from the begining. If you could find the parts, they would
be extremely expensive, and you want to be sure they are the culprit.
How is the compression? Have you tried a squirt of fuel in the carb throat
test?

 

[randyw]

Attached a second picture of the back of the module. After a closer look it is pretty clear the entire part would need to be replaced if it is in fact the ignition module. I was also advised if I replace the mudule I should also replace the flywheel.
Fish, I had great spark when I pulled the plug from the saw, connected it to the boot/wire and gave a couple easy pulls. Didn't do a compression check but I had good pressure against my thumb, and it was signifigantly harder to pull once the plug was back in the saw. FYI my saw mechanic is telling me to (try) and find a new ignition. I am perplexed. Could I have a bad ignition but still have spark?
-rw

 

[Fish]

I doubt it. I suppose it is possible that the spark's timing could be off, but
I would assume it is good.
Since it sounds like it is fairly torn down, remove the carb or muffler and
take a peek at the piston.

 

[Brmorgan]

I agree with Fish, you don't want to be trying to source an electronic 041 ignition unless you really really need to - they aren't cheap. And if you're getting a nice blue spark then there's a 99% chance it's something else going on here. If it's getting fuel and a spark it should at least backfire or give your arm a good pullback even if it's out of time somehow. Look at everything else first - fuel system including tank filter, carb, and impulse hose; check for compression; check for piston damage... Also, 041s were problematic for air leaks because there's practically half a dozen various gaskets involved in the intake assembly stack and all it takes is one to fail to cause problems.

If you swap your ignition module with one identical to it, then you shouldn't need to swap your flywheel. Unless of course the flywheel key is sheared, which would throw it out of time and could cause your non-starting problem. If you go to points ignition or even a SEM electronic though, the flywheel will have to be swapped. I've read about some newer electronic modules getting "stuck" in an advanced timing mode where you'll get spark but it won't start, but from what I've seen here these old Stihl electronic modules seem to just die. I've never seen a Bosch like yours yet though; only worked on a couple SEM electronic ones so far - the rest were points.

 

[ritchienw]

041AV Ignition Module/Coil

Hello,
I'am trying to learn more about the electronic ignition module on my 041.
I have attached a picture of the ignition with labels (A,B,C) and I am trying to determine what each part is? My saw had spark but no fire. Can anyone help me determine which part I need to replace? Maybe a lead on where to find the part? :help:
TIA,
-rw

I have the same module in my 041AV..electronic..did you find replacement, if so where? Would be interested..I have no spark on mine..great condition, however, no fire..help as well..NWR

 

[ritchienw]

041AV Ignition Module/Coil

Hello,
I'am trying to learn more about the electronic ignition module on my 041.
I have attached a picture of the ignition with labels (A,B,C) and I am trying to determine what each part is? My saw had spark but no fire. Can anyone help me determine which part I need to replace? Maybe a lead on where to find the part? :help:
TIA,
-rw

I have the same module in my 041AV..electronic..did you find replacement, if so where? Would be interested..I have no spark on mine..great condition, however, no fire..help as well..NWR My coil has SEM NO 100 48000 the armature is SEM Type G E..made in Sweden stamped on same..

 

[jockeydeuce]

I have the same module in my 041AV..electronic..did you find replacement, if so where? Would be interested..I have no spark on mine..great condition, however, no fire..help as well..NWR My coil has SEM NO 100 48000 the armature is SEM Type G E..made in Sweden stamped on same..

Sounds like you have an SEM, not a Bosch.....I bet the back of the module says type G6/E.

 

[ritchienw]

Sounds like you have an SEM, not a Bosch.....I bet the back of the module says type G6/E.

Hi Jockeydeuce..that was fast..living in Canada as well, B.C., you are right..if made in Sweden..bosch..looking on some websites now for the part..see here Stihl number for coil is 1115-404-3200 and the Bosch is 2 204 211 052..the search is ongoing, will let you know when running..thanks..NWR

 

[hotshot]

Twisted up information

Hi Jockeydeuce..that was fast..living in Canada as well, B.C., you are right..if made in Sweden..bosch..looking on some websites now for the part..see here Stihl number for coil is 1115-404-3200 and the Bosch is 2 204 211 052..the search is ongoing, will let you know when running..thanks..NWR

The bold coil numbers you gave above are for the Bosch points type set-up.

If you do have the different SEM G/E, then the black replaceable coil is number 1110-404-3210 (and it does not have the charging plates "winged laminate plates" sticking out like the 3200.

If you have the third option of the Bosch CDI type, like the one pictured in the start of this old thread, then there was no coil replacement, they replaced the whole stator unit as an assembly. Then there was even a fourth type Bosch CDI with a CD pack and a wire harness routed to it, but I've never seen one of those in the US. However, it is rare that the coils themselves are ever faulty, but is very common for the Darlington transistors/trigger units to go out. Another issue is that you have to have the matching flywheel for each type... and they were all different too!

Bosch were generally German made & SEM were Swedish made at the time of production of these old parts

 

[ritchienw]

The bold coil numbers you gave above are for the Bosch points type set-up.

If you do have the different SEM G/E, then the black replaceable coil is number 1110-404-3210 (and it does not have the charging plates "winged laminate plates" sticking out like the 3200.

If you have the third option of the Bosch CDI type, like the one pictured in the start of this old thread, then there was no coil replacement, they replaced the whole stator unit as an assembly. Then there was even a fourth type Bosch CDI with a CD pack and a wire harness routed to it, but I've never seen one of those in the US. However, it is rare that the coils themselves are ever faulty, but is very common for the Darlington transistors/trigger units to go out. Another issue is that you have to have the matching flywheel for each type... and they were all different too!

Bosch were generally German made & SEM were Swedish made at the time of production of these old parts

Hotshot..indeed, I see the number you quoted is the correct number for my coil..from the parts list I found..mine does not have the "winged laminate plates", will have to test the coil before I go further..the ground was good, just no spark..will check the switch as well..would be nice to hear here purr once more, what a saw..will keep hunting the web..thanks for the input NWR

 

[hotshot]

You should go to the sticky thread "Beg for Manuals", and ask for someone to send you the 041 Service Manual.

If you want to check your current coil with an ohmmeter, the primary & secondary resistance ranges are 0.4 to 0.5 & then 2.7K to 3.3K ohms respectively.

If either is open (no continuity), then it is indeed failed. This SEM on Flea Bay auction #230970807011 was sold a few weeks ago, but look at the pics and see if it matches yours.

 

[ritchienw]

You should go to the sticky thread "Beg for Manuals", and ask for someone to send you the 041 Service Manual.

If you want to check your current coil with an ohmmeter, the primary & secondary resistance ranges are 0.4 to 0.5 & then 2.7K to 3.3K ohms respectively.

If either is open (no continuity), then it is indeed failed. This SEM on Flea Bay auction #230970807011 was sold a few weeks ago, but look at the pics and see if it matches yours.

Hot Shot..will do..let you know after I do the checks..I found my part matches the picture in the Stihl 041 Assembly manual..for the ignition system..the stator plate #1110 400 0808 and the coil #1110 404 3210..so on the right track, now to find one? I see in Europe, they are really expensive..time consuming, but worth it..thank NWR