Stihl 056 bosch ignition

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Of course-- 12v battery and pick up clamped to the spark plug wire on the saw. You HAVE to move the base plate and coil to change timing. I have a four magnet Bosch flywheel. And it has north/south magnets to trigger the coil. Moving the flywheel only made the timing light dimmer, it did not change when the spark occurred.
 
Yes, the electronic Saegenspezi they sell on German eBay for a Dolmar 133.

How about some starting tips for this beast? Pull two times with choke closed and open throttle locked on, then turn on switch, position choke to half, and it is supposed to cold start? Or is there a better method for cold starts? I have a problem doing this because the 133 stalls when I give it gas then doesn't want to start again. I get tired pulling the rope.
 
Start a new thread on that.

Call it cold starting a Dolly 133, or whatever you want.

You need to pull it & listen/hear the saw burp or briefly start with it set on full choke, then flip the choke off.

It may take a half dozen pulls or more on a dry carb to get fuel up into it.
 
I'm not having good luck today. I tried to start the 133 and choked it then unchoked it flipped the switch on and spent good 5-10 minutes and not even a kick! So rechecked with timing light, still the same 26 BTDC. Spark plug had a thin light when tested, didn't look strong.

So I checked the plug using my electric start Honda 5.5 engine and got a blinding flash off the NGK plug holding it against a ground. It's funny when I was playing with the chainsaw timing before, it was starting with the easiest pull and the timing was wrong. Now it is right and the ******* won't start! Well, it did start once, but the flywheel nut was not tight and I broke the woodruff key, but that shouldn't have hurt anything.

Tell me something...
 
I just thought of something-- I need to retime the flywheel to he new coil timing position. They work as a pair.
 
Retimed/repositioned flywheel (C C 44mm) and she fired up and ran great. This baby has some power! Just need to get the carb dialed in.

Picture shows oval hole normally used for mounting screw, mounting screw now holds the coil. 44mm difference.IMG_20180708_133131277.jpg
 
Thought I would give an update on my Sachs Dolmar 133 ignition replacement. The last few posts explained how I got my saw running using the German ignition replacement. However, it worked for awhile then quit. So I put it aside until this spring when I needed to cut wood for next winter.

So when I tried to get it going recently, it would start and then quickly die, then not fire at all. Just like it did when I got it with the original SEM GE ignition.

So after several tests, I determined that the ignition module was the problem. I put a Nova 2 and it fired right up and ran for 5 minutes and died. WTF. I did a Google search and finally found a Homelite chainsaw forum that people were having the same problem with Nova 2's mounted INSIDE the flywheel, and that the solution was to mount the ignition module out and away from the heat.

So I got another Nova (a newer version) and mounted it next to the carb so the only thing inside the flywheel is the coil, and ran the wires to the kill switch.

I just did a 20 minute cutting test and the saw ran perfectly. HTH
 
Thought I would give an update on my Sachs Dolmar 133 ignition replacement. The last few posts explained how I got my saw running using the German ignition replacement. However, it worked for awhile then quit. So I put it aside until this spring when I needed to cut wood for next winter.

So when I tried to get it going recently, it would start and then quickly die, then not fire at all. Just like it did when I got it with the original SEM GE ignition.

So after several tests, I determined that the ignition module was the problem. I put a Nova 2 and it fired right up and ran for 5 minutes and died. WTF. I did a Google search and finally found a Homelite chainsaw forum that people were having the same problem with Nova 2's mounted INSIDE the flywheel, and that the solution was to mount the ignition module out and away from the heat.

So I got another Nova (a newer version) and mounted it next to the carb so the only thing inside the flywheel is the coil, and ran the wires to the kill switch.

I just did a 20 minute cutting test and the saw ran perfectly. HTH
 
A couple of more insights into upgrading from the SEM GE to an ignition module Nova2. If you don't want to buy a Bosch type flywheel with the magnets (N-South) 180 degrees apart, you can get your 4 magnet SEM GE to work. Only two of the sem magnets are magnetic, the other two are non-magnetic and are only for balancing the flywheel.

Using a propane torch, remove the south magnet and screws, and remove the dummy .agnet
 
I just came across a good video from Yankee Nimrod , which shows how he applied the Stihl 056 AV ignition coil fix (adding a capacitor). I could use some help on two items:
1. What size capacitor is used? (I see info earlier in this thread, but couldn't find that exact one online)
2. The kill switch wire was cut and glued-over in the video. What is the purpose of cutting the kill wire, and how is the kill switch functionality restored?
Thank you in advance for your insight.
 
I just came across a good video from Yankee Nimrod , which shows how he applied the Stihl 056 AV ignition coil fix (adding a capacitor). I could use some help on two items:
1. What size capacitor is used? (I see info earlier in this thread, but couldn't find that exact one online)
2. The kill switch wire was cut and glued-over in the video. What is the purpose of cutting the kill wire, and how is the kill switch functionality restored?
Thank you in advance for your insight.

The capacitor required is called a run capacitor.
The specs are: 0.8 micro farad, 450 volt, metallized polypropylene metal film capacitors.
They sell for approximately $10.00, depending on the seller and the number of pieces you purchase.

I almost forgot to add:
The best way to increase the life and the reliability of this unit, is to run the wire out from under the flywheel, and mount it on the outside of the flywheel. One person that was experimenting with these caps, stated that they do get hot, and do better with lots of air circulating to keep it cool.
Bob
 
Very interesting thread! There are things I don't understand though. For example what problem is being solved, the high voltage coil opening up or the control module. Adding a trigger unit just replaces the control circuitry and has ziltch to do with the high voltage transformer heating problem. Next, I don't know how those trigger modules function. Those in the Bosch ignition use a separate coil from the high voltage circuit to provide the stored energy that gets dumped by the thyristor into the high voltage transformer. But if it works ... it works. You cannot ******** physics. OH and EBay sells those trigger units now for big bucks... over $50 each.

Obviously I share the same woos with my Bosch ignition used in my 056. I just took a chance and ordered the high voltage transformer for a TS350 (thanks to getting info here in the forums) and intend to give it a try. If the mechanics are different than what I now have, well then it will not work. But for $30 delivered from EBay I thought it is worth a shot.

General comment! Electronic designs for circuits such as those Bosch used in the 056 and others should have had a better reliability analysis before they were implemented into chainsaws. There is no black magic here but there is poor electrical engineering that all owners of those early saw designs now suffer with while trying to keep an old work horse functioning.

Foggy
Hi Foggy,
I have an 056 that has a bosch flywheel. The person that owned it before had an aftermarket module which will not work. How can I get this saw running again. 301-674-6267 Thank you Chris Harmon Ft Valley Va
 
I just came across a good video from Yankee Nimrod , which shows how he applied the Stihl 056 AV ignition coil fix (adding a capacitor). I could use some help on two items:
1. What size capacitor is used? (I see info earlier in this thread, but couldn't find that exact one online)
2. The kill switch wire was cut and glued-over in the video. What is the purpose of cutting the kill wire, and how is the kill switch functionality restored?
Thank you in advance for your insight.
 
Doug were you able to make this repair?
Charmon23, I tried to repair, and could not get the cover off of the ignition coil. My home-made puller tool worked the first time (about 5 years ago), but this time it was so stuck that the holes were starting to strip when I tightened down the tool. After much thought, I chose to sell it in "not working" condition. I sold it to someone who is confident that he can get it working. I sure hope he get it going, as it is a powerful saw that should last a lot longer.
 
The capacitor required is called a run capacitor.
The specs are: 0.8 micro farad, 450 volt, metallized polypropylene metal film capacitors.
They sell for approximately $10.00, depending on the seller and the number of pieces you purchase.

I almost forgot to add:
The best way to increase the life and the reliability of this unit, is to run the wire out from under the flywheel, and mount it on the outside of the flywheel. One person that was experimenting with these caps, stated that they do get hot, and do better with lots of air circulating to keep it cool.
Bob
Charmon23, I just saw your questions from earlier. Above is info on the capacitor. I found one that met these specs at mouser.com. Here's one that I ordered. It's not the exact specs, but they have a variety to choose from. https://www.mouser.com/ProductDetai...YAJq/JVLvew==&countrycode=US&currencycode=USD
You also asked why the person cut the kill switch, and how the kill switch functionality was restored. I commented on the video and he replied that he uses the choke to kill the engine. I would prefer to restore the kill switch functionality. Perhaps the original wire could be used, and just heat-shrink covered so it doesn't short-out against the engine.
 
Charmon23, I just saw your questions from earlier. Above is info on the capacitor. I found one that met these specs at mouser.com. Here's one that I ordered. It's not the exact specs, but they have a variety to choose from. https://www.mouser.com/ProductDetail/kemet/r75mr4100aa40k/?qs=uwUAEbwHiLeYAJq/JVLvew==&countrycode=US&currencycode=USD
You also asked why the person cut the kill switch, and how the kill switch functionality was restored. I commented on the video and he replied that he uses the choke to kill the engine. I would prefer to restore the kill switch functionality. Perhaps the original wire could be used, and just heat-shrink covered so it doesn't short-out against the engine.
Doug,
Thanks so much I think I got this all figured out now waiting for the part
Merry Christmas
Chris
 
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