Stihl 056 bosch ignition

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Timing?

Did you check timing with timing light? And if you did does it chang as saw speeds up?
 
Bosch ignition repair

This is a brilliant idea,have been looking for a fix,figured the module could be rebuilt with conventional available components rather than just settling for the manufacturers "NLA"(Which is cheesy product support anyways)I wrote stihl #####ing about letting a winner like the 056 fade into obsolesence,they wrote back with a list of outfits specializing in obsolete saw parts....I bought a module and flywheel from ebay and fixed my ignition failure,but have been staring at my old module now since I found this fix,planning my next failure.....Your trigger is shown mounted 90 degrees from the ignition coil as opposed to the 180 degree original Bosch trigger mount,this doesn't make a difference?Is there a killswitch lead coming off that available trigger?Finally,the electronics you sawed off,must be the trigger you used houses all that now?Oh one more thing....the flywheel tweak you mention(half a keyway advance)is that necessary or can timing be adjusted by the slots in the backplate?
 
I'm working on a late 70's 045AV and the keyway doesn't allow for any angular adjustment of the flywheel on the crankshaft. For those guys that made the keyway modification, how was it done?


This is a brilliant idea,have been looking for a fix,figured the module could be rebuilt with conventional available components rather than just settling for the manufacturers "NLA"(Which is cheesy product support anyways)I wrote stihl #####ing about letting a winner like the 056 fade into obsolesence,they wrote back with a list of outfits specializing in obsolete saw parts....I bought a module and flywheel from ebay and fixed my ignition failure,but have been staring at my old module now since I found this fix,planning my next failure.....Your trigger is shown mounted 90 degrees from the ignition coil as opposed to the 180 degree original Bosch trigger mount,this doesn't make a difference?Is there a killswitch lead coming off that available trigger?Finally,the electronics you sawed off,must be the trigger you used houses all that now?Oh one more thing....the flywheel tweak you mention(half a keyway advance)is that necessary or can timing be adjusted by the slots in the backplate?
 
Remove the key from the crankshaft and file or grind to 1/2 it's width. Re-assemble and rotate the flywheel to the desired location. If that doesn't give you enough adjustment, you can very carefully use an abrasive cutoff wheel the same dia. as the key and widen the key slot as required.
 
Sorry for not keeping up with things. I haven't put a timing light on it yet. Its still running like a champ though I think the timing is a little slow. I haven't even moved the module from under the flywheel. As for Sawhawg's ?. Module position doesn't matter. You could leave it in the truck if you had a long enough wire;) I just choke the saw to kill it but you could just ground the trigger wire to kill it. Yes, all the fairy dust is in the module now. To reposition the flywheel I just removed the key. The key is really just for indexing purposes.
 
Ive copied what was done on this thread but I cut a slot in the timing plate and moved it rather than move the flywheel. I have some pics somewhere and wanted to start a thread but havent had time.:msp_smile:
 
Good idea. Everything work ok?

Yes and no. I had to get a longer sparkplug wire. The powerhead ran ok then put together and lost spark. Had to take back apart to put new wire on. Havent put whole saw back together yet. Have some good pics but cant find.:msp_biggrin:
 
pictures/instructions

I was searching for a fix for my grandfather's 045av super and found this thread I love this idea instead of $150 replacement from Germany. If anyone has put together pics and instructions on the modification that would be great. Gramps is wanting to go cut wood with me this spring and I would like to get his saw running.
 
Another data point here. I have an 056 Magnum that runs for a few minutes until it gets warm and then it dies until it cools off. I installed a Nova II and immediately got spark. Had to advance the flywheel about the width of the key for the spark to produce fire. What this thread needs is an explanation even an electrical dummy like me can follow about how to get the flywheel rotated the "right" amount. Right now the saw runs well in the garage, but how it does in wood remains to be seen. I haven't noticed any sign of kickback when starting, so I'm guessing I didn't advance too much.

In the meantime, I just want to add a big "THANK YOU" to blind hog for finding and reporting this fix.
 
I am in the process of trying this trick with an 045 and bosch coil. Is the chip positive grounded or negative grounded for this saw? I tried negative and no luck with spark.

I've done this mod on two 056s so far. I just followed the directions that came with the chips - pretty sure they called for negative ground. I will say that on my first attempt, I thought that the chip wasn't working because I couldn't get any kind of hit when trying to start. Then I did what I should have done first - check for spark with the plug removed. There was plenty of spark so I figured the timing had to be diddled as outlined by blind hog. As soon as I did that, the saw fired up without difficulty. On the second saw, I immediately modified the timing and the saw started right away. Good luck!
 
Ran the 045 and it made 6 long cuts and died. I let it cool off for an hour and it started again. I wonder if the coil is bad. Even with the nova chip the spark will not jump a tester gap but i can see a weak spark. I was reading about a 041 coil in its place as I have the bosch flywheel. Any idea which 041 coil I need to get?
 
I will try that this weekend. Did you cut the flywheel key or slot the ignition mounting plate to mod the timing?

Sorry I missed this earlier. I removed the key and rotated the flywheel CCW (advance) approximately one key width. I'm planning to bring these 056s to the GTG next month in hopes of getting a lesson in fine tuning timing mods like this.
 
I will try that this weekend. Did you cut the flywheel key or slot the ignition mounting plate to mod the timing?

The 056 I did I slotted the ignition plate and had to get a longer sparkplug wire. I really was not comfortable with removing the key and advancing the flywheel on the crank.:)
 
The saw did run fine when it was running with the flywheel 1 key width CCW. I just need to figure our what coil to use that is economical and if it is the coil or the trigger that is getting hot. I am leaning toward the coil as the spark is very weak even when cold. This is with a new plug wire , plug and wire clip.
 
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