Stihl 056 bosch ignition

[psuiewalsh]

There was an thread here about adv it 1/2 key. Magnets must not care. It ran until it gets hot.

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[blind hog]

well, I thought my 056 finally died today. It quit me in the woods the other day. Pulled the spark plug out of my 017 and still wouldn't run. Tore into it today, and the first thing i noticed was that it had weak spark. I never did move the ign module out from under the flywheel so i figured I'd go ahead and install the new ign module i bought for it 3 years ago lol. Couldn't remember all the eccentricities of the timing so i pulled up this old thread to look at my old fix. Moved the module into the carb house (the bolt that holds the back handle housing). Also hooked up kill switch. Re-installed flywheel one full keyway advanced as per atpchas's recommendation ( 1/2 keyway did seem retarded). Still would not start. Messed with timing, pulled exhaust, tried starting fluid, stomped around and cussed. Finally put ANOTHER spark plug in it and BANG! it fired right up. 1 cylinder + 1 bad plug = no happy. Much peppier with full key of advance (good call atpchas). Now I realize that I left some things out on my old fix. Back in the old go-cart racing days we advanced ignition timing with an "offset" key. When we started racing high rpm (10,000 +) briggs modifieds with super light flywheels, offset keys just wouldn't live. The solution was to pull the key out and "red loctite" the flywheel to the crank. Trust me, you won't "spin the flywheel if you loctite it. Flywheel keys don't hold the flywheel in place period. The tapered (interference) fit is what keeps the flywheel in place. the key simply assures that you re-install in the same position every time. In order to know where the crank keyway is when installing the flywheel I marked the end of the crank with a punch. Also, building a fw puller is super simple. Big bolt, big nut, welded to 3/8 steel ring and drill 3 holes. Long bolts from hardware store.

 

[blind hog]

Oh yeah, psuiewalsh. "Getting hot and then dying" is very characteristic of a bad coil. I don't know anything about the "nova" chip. I do know that the "chip" is just a trigger, it adds nothing to the spark. It receives no power therefore creates no power.

 

[psuiewalsh]

Nice. I ended up buying a parts saw and sold the saw a while after that. I still have the chip setup with a coil and flywheel though if you need.

 

[sachsmo]

Several models of Sachs Dolmar use that Bosch ignition.

On the SDs the mounting plate is slotted, super easy to advance timing, but you will know if'n you go too far!

 

[dieselpilot]

Recently solved my Stihl 056 Bosch ignition problem. After visiting this and other websites looking for answers to the "it runs for about 20 minutes and then dies" problem, I discovered many people having the same issue. My saw finally quit firing at all. I'm sure someone has already posted this solution but i haven't seen it. It's fairly obvious that the bottom (detachable) portion of the ignition unit is the coil. Cut the jumper wire from the coil to the (epoxy filled) electronics, solder this lead to a 1118-400-1001 trigger unit lead (26.00 from stihl dealer), ground the module, and the ignition will fire, assuming that the coil itself is not the issue but rather the electronics. Strangely enough the saw still would not fire. Blaming the lack of combustion on ignition timing, I pulled the key out of the crankshaft and began rotating the flywheel a few degrees in either direction. Retarding the flywheel (clockwise) about half a keyway created the desired response. I undoubtedly need to fine tune the ignition timing, but the saw runs perfectly. I then removed the top (detachable) bosch trigger unit and bandsawed off the (epoxy filled) electronics in order to mount the new trigger unit properly.

The pictures of this mod aren't accessible anymore. Does anyone have any pictures of a modded ignition unit ? Thanks!!

 

[blind hog]

They should be on my old phone. I'll try to find them.

 

[dieselpilot]

They should be on my old phone. I'll try to find them.

Thanks very much! I have 2 045s and 2 056s so this mod will be essential for me in the future, as I love and use these saws. Thanks again.

 

[blind hog]

Here they are.

 

[Mastermind]

Good stuffs.....

 

[dieselpilot]

Perfect! Thanks very much!! I was having a hard time visualizing the final product.

 

[Trzebs13]

Has any one else got this to work? I tried it with 2 different coils and no spark.

 

[rickyrooster]

If this fix works well this should be made into a sticky. The 056 stihls down fall is the ignition. Being able to get them up and running again is priceless. Rick!

 

[blind hog]

I have moved the module into the carb compartment since these pictures where taken. Fix works great and is simple. The trick is to advance the flywheel one key-width (counter clockwise). Just remove the key and rotate until the side of the flywheel keyway is even with the opposite side of the crank keyway. Tighten it down and dont worry about it. If the problem with the ignition is the coil then of course the fix is useless. I have seen a thread on this forum in which you can get a replacement ignition for these saws. Looks like it comes from germany and sells for 125.00. Sells on ebay from seller saegenspezi. The guy said he installed it and it fired right up. Hasn't cut with it yet. Looks sort of like what I ended up with if I would have put the trigger module in shrink tube.

 

[dieselpilot]

I have moved the module into the carb compartment since these pictures where taken. Fix works great and is simple. The trick is to advance the flywheel one key-width (counter clockwise). Just remove the key and rotate until the side of the flywheel keyway is even with the opposite side of the crank keyway. Tighten it down and dont worry about it. If the problem with the ignition is the coil then of course the fix is useless. I have seen a thread on this forum in which you can get a replacement ignition for these saws. Looks like it comes from germany and sells for 125.00. Sells on ebay from seller saegenspezi. The guy said he installed it and it fired right up. Hasn't cut with it yet. Looks sort of like what I ended up with if I would have put the trigger module in shrink tube.

Just to keep this outstanding thread fully documented, could you post some pics of the setup as it exists today? The more detailed and plentiful the pictures the better!!!

 

[Trzebs13]

Would this be along the same theory?

http://cgi.ebay.com/ws/eBayISAPI.dl...akeTrack=true&ssPageName=VIP:watchlink:top:en



I dug the one out that I tried and noticed that the trigger unit I got looks different than yours. Maybe what it my issue.

 

[trappermike]

I our shop in the 80's another mechanic and I ended up doing the same thing to an 056 to see if it would work,repair a $200 Bosch ignition with a $7 aftermarket part sold as Atom or Minitron-a little electronic module like the ones you are using.We hacksawed off the electronics in epoxy part and wired in the module,we didn't do anything with the timing and we got good spark,We were jubilant and had a cheap repair for the Bosch ignition so we repaired a few 056's that way.
The problem for us was they all soon died,especially after a faller raised hell on the phone,I had to drive in the shop truck 2 hours north in winter to the little town he was working from and install a new Bosch ign. at our expense, and I had to do the job on the shop's concrete floor not the workbench because he was mad. The Boss banned us doing that anymore.Another shop had been doing the same thing in Gorman-Rupp pumps and the little modules replaced an expensive ignition,but they all soon failed for him too after a while.
In the end we concluded this;
-The little electronic modules work great in most cases-Where the flywheel has it's magnets located in just one spot on the flywheel's circumference.
-The electronic modules will fire well but die after a short while when the flywheel of the ignition involved has magnets located all around it's circumference.(Like a Bosch type on 056)
I also back then put one of the little units on my friend's kid's Yamaha 80,replacing the points,it sparked well and ran great,but a week or 2 later it was dead,no spark,and it's flywheel had magnets all the way around.
I'm not trying to rain on your parade or anything and I'm hoping the newer models now have better electronics and your Bosch fixes will be good.I've got a new one to install in my old 275 Canadien.
But maybe just be cautious and see how the first few work out and note what type flywheel the motor has when contemplating installation...

 

[dieselpilot]

I our shop in the 80's another mechanic and I ended up doing the same thing to an 056 to see if it would work,repair a $200 Bosch ignition with a $7 aftermarket part sold as Atom or Minitron-a little electronic module like the ones you are using.We hacksawed off the electronics in epoxy part and wired in the module,we didn't do anything with the timing and we got good spark,We were jubilant and had a cheap repair for the Bosch ignition so we repaired a few 056's that way.
The problem for us was they all soon died,especially after a faller raised hell on the phone,I had to drive in the shop truck 2 hours north in winter to the little town he was working from and install a new Bosch ign. at our expense, and I had to do the job on the shop's concrete floor not the workbench because he was mad. The Boss banned us doing that anymore.Another shop had been doing the same thing in Gorman-Rupp pumps and the little modules replaced an expensive ignition,but they all soon failed for him too after a while.
In the end we concluded this;
-The little electronic modules work great in most cases-Where the flywheel has it's magnets located in just one spot on the flywheel's circumference.
-The electronic modules will fire well but die after a short while when the flywheel of the ignition involved has magnets located all around it's circumference.(Like a Bosch type on 056)
I also back then put one of the little units on my friend's kid's Yamaha 80,replacing the points,it sparked well and ran great,but a week or 2 later it was dead,no spark,and it's flywheel had magnets all the way around.
I'm not trying to rain on your parade or anything and I'm hoping the newer models now have better electronics and your Bosch fixes will be good.I've got a new one to install in my old 275 Canadien.
But maybe just be cautious and see how the first few work out and note what type flywheel the motor has when contemplating installation...

Blind Hog moved his trigger module into the carb box and away from the flywheel magnets (a pic would be helpful ). Apparently, he didn`t have a problem before he moved it. He is using a quality Stihl part (1118 400 1001) which may help.

 

[blind hog]

Luckily I'm not trying to when any prizes or popularity contests. This repair has worked for me for nearly three years. The 056 is my primary saw. I farm over 1000 acres and heat exclusively with wood. Just trying to give an idea of frequency of use. I can't imagine that the magneto would fail due to a different trigger being used. Magnetos tend to be EXTREMELY durable. By changing the trigger (module) the magnetos environment hasn't been changed. It is still being charged by the same magnets. The trigger simply interrupts the flow of current through the primary coil causing the voltage spike. I guess the wild card here is the multiple magnets as trappermike said. I'm not sure why there are so many unless it has something to do with either the shape of the armature (not shaped like a 'U') or recovery time. In any case I was very surprised to see that little module live for two years under the flywheel. Normally I try to locate them somewhere much kinder but I didnt really expect this thing to work in the first place. As stated above I have replaced the original module that I used. Not because it quit working but rather because it was falling apart. Lots of vibration and harmonics under that flywheel I'd say. I'll get new pictures up asap.

 

[blind hog]

Oh yeah. It seems like someone else tried this with a different brand of trigger and it wouldn't work at all. Maybe their magneto (which I've been calling a coil up till now) was bad or maybe there is a difference in the sensitivity of the modules? That looks perfect to me Trzebs13.