SUCCESS!!! Just repaired Stihl 045/056 Bosch electronic ignition!!!!!

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Foggy (and all others) Sorry I'm such a scatterbrain and write as such.
I was zero-wiping ,reformatting and running memory tests, etc on a used laptop
and whilst waiting, just sort of got lost in my fragmented thoughts here.
While typing I seem to lose about 70~80 percent of what I'm thinking
and it can often become a real train wreck after having also been truncated by my carpal tunnel typing speed.
 
Sorry-- I don't know anything about that particular ignition.
heres a que.....is it a bosch coil on a olympyk saw??? on the 945/950, those are known for taking out coils!!!! and theres no efco or other olympyk coil that works in its place!!! wonder if that's what happens to them,,as they are where there is near no airflow????
 
What I have found is that it is ...............NOT!!!!!...................THE CALLED COILS that are the problem. SO FAR, I CAN SHOUT...............FORGET ABOUT THE HIGH VOLTAGE PULSE TRANSFORMER ALONG WITH THE CHARGING INDUCTOR!!!!

Now what the heck is going on with me an my fix???? Mo. Jim was the only person to date to send a failed ignition for me to analyze. I can report the failure I found is identical to what I found earlier. It is an internal capacitor. I will be posting pictures, hopefully within a day or two. I have already started taking pictures of the repair to the ignition that Jim provided. My next step is to make a complete installation into my 056 taking pictures of each step so others WITHOUT TECHNICAL SKILLS can make the needed repair. Those of you who have this problem, hang onto your failed ignitions, make the repairs I will outline. Then report back to the forum your results. Your feedback is important to verify the fix.

As to the Olympic..... I haven't a clue what their problems are. IF they use the Bosch ignition... one that closely resembles the Bosch used in the 045/056 then there is a high likelihood it has the same failure mode.

Patience---- I should have this all together before the week is out.

Foggy
 
Please see below for another use of the Bosch ignition

http://www.arboristsite.com/community/threads/dolmar-120-ignition.252526/#post-4793439

There, Sachsmo mentions he has repair several/many of these ignitions. And I believe he has! I have ignored the shutdown wire which can be obvious with its insulation falling off. I have concentrated on fixing a failure in the electronic box. Incidentally, the ignition I mention above from Mo. Jim, the shut down wire had been repaired and without doubt, it required repair.
 
TEARS ON MY PILLOW, BLISTERS ON MY HAND! BUT THE IGNITION FIX WORKS!!!!! And when you see the repair pictures you will see why the new capacitor will never heat up as the Bosch's storage capacitor most likely did.

Ok guys this is what happened and remember, no mechanic here. I got my 056 together today! Checked the spark, nice blue glow so that is fine. My saw however takes two men and a boy to pull the starter code. The guy I purchased it from told me he installed the larger cylinder head & piston to upgrade it to the equivalent of the Magnum. Does the Magnum have a different starting mechanism to provide greater mechanical advantage??

Now back to my tears. I squirted some starting fluid into the carburetor, set the throttle to high using the throttle lock (BIG MISTAKE), Yanked on the pull rope and the thing started with a raw, most likely soaring to over 10K RPMs for all of about 3-4 seconds. After that there was again peace in the valley. Pulled the starting rope....no resistance at all now! Pulled the plug and of course there could be no resistance because the piston was not moving.

Took it back to my work bench, pull the starter mechanism off and lo and be hold!!!! The nut holding the flywheel was loose...and I I had tightened this originally. But again, no mechanic here. I need to pull the flywheel and check the key before I do anything more with it. Whatever damage I stupidly caused, the ignition is just fine. I will try to get the pictures posted along with instructions later tonight, if not it will be tomorrow.

More later

Foggy
 


YES!!!!!!!!!!! THESE ARE WHAT YOU NEED!!!!!!!!!!!!!!!!!

But if things go right and electrically speaking, I believe they will... then you will only need one (1)! Heck, I would put an ad right here in the forums offering the other 9 for sale......maybe $20 each : - )

Foggy
 
THE FIX!!!!

This may be a little verbose but my intent is to convey all that is needed to implement the fix. So first, I will start with a failed ignition showing and describing the repair steps. The tools you will need are: soldering iron....25 watts should work using solder designed for electronic work NOT PLUMBING SOLDER, I recommend an inexpensive heat gun...Harbor Freight maybe but with care you can work without one, epoxy designed for plastics.... HD or Lowes for about $5, electric drill with a 1/4 or so bit, a wire crimp tool with a lug (see pictures), and last I used a hot glue gun to sort of seal up the mounted new capacitor. The hot glue I used is industrial quality and you can get by substituting caulking selected from one of the many types available. And of course both a blade and Philips screwdriver will come in handy.P1010720.JPG

Heat the small section as shown in the above picture, try to avoid heating the pulse transformer. The potting does not have to melt, just soften so a small section can be removed with a screwdriver or other suitable tool.
P1010739.JPG

DON'T GET CARRIED AWAY chipping out that potting material! Take you time doing this. In teh above picture you see the shinny tinned copper PC run. The next picture will show where I want you to cut. Try to leave about 1/8" gap.
P1010720.JPG P1010739.JPG P1010740.JPG

Heat up your soldering iron and get ready to solder an insulated wire onto the right hand side of the exposed PC bus (not the short piece to the left). I salvaged my wire from an old computer power supply and because I added 3 wires, I used two different colors so I could tell which went where. 18 gauge stranded wire will work fine. Please! Don't use a length of solid core house wire, your asking for trouble.P1010742.JPG

I tucked that yellow wire under the pulse transformer. There is another wire that you add using a crimped lug. Secure it under the screw (holding the pulse transformer) above where you made your cut. Don't tighten the screw yet. Later when you install the ignition that lug will be in the way trying to get the mounting screw into the saw proper. That is when you will tighten the lug down. OH-- avoid using the yellow sized lugs. They are much larger and can get in the way of the rotating flywheel. Adding a third wire is entirely up to you, I used black so I would not mix it with the others. I cut the shutdown wire that goes to the on/off switch and replaced it with this third wire. If you don't bother replacing the shutdown wire, take care that the old wire's insulation is intact, cover it, tape it or just cut it out, it your decision. Remember if you disable that wire, you disable the on/off circuit to shut the saw off.P1010762.JPG

Now here is where each of you can add value! I squeezed all three wires into the shared hole with the spark plug wire. There is a rubber grommet in the hole so they can be made to fit. Maybe you want to drill a new hole....???? Anyway, that is left for you to decide. After pushing the wires into the grommet, I used a piece of steel wire... coat hanger will work... shaped with a hook on the end to fish the wires out. Next I drilled 3 holes in the plastic air shield....1/4" or thereaboiut should work. Tow of the holes is for a tie wrap that I used to hold the new capacitor in place. The other hole is for the two yellow wires to pass through. Note I left the wires on the outside of the plastic to avoid them getting caught with the flywheel's fan. That's why you need to drill a hole for the wires.

P1010775.JPG

Scrub the plastic under the tie wrap with alcohol and also scrub the new capacitor with the same. Mix up your epoxy. Paint generous amount of epoxy across the section under the tie wrap and on one side of the new capacitor. The capacitor will seat under the tie wrap with its two wire terminals pointing downward toward the flywheel. MAKE SURE you seat that cap such that it has space for the wires to be soldered to the terminals such that they don't get damaged by the fan. That is important! After pushing the new cap into place, tighten up on the tie wrap. Next pull both yellow wires into place and cut them leaving enough length to strip 1/4" or so needed to solder one wire to each terminal.

P1010777.JPG

I used my trusty old, beat up glue gun to bury the new capacitor along with the new wires with hot glue. This ensures they will not move about with the saw's vibration.


P1010779.JPG


P1010781.JPG


IF YOU GOT THIS FAR---------- YOU HAVE COMPLETED THE FIX!!!!!!!!!!

You can test the fix after the epoxy dries along with the hot glue or caulking or whatever you select to use.

Assemble the saw so you can pull the starter rope....remove the spark plug from the engine, clip a grounding wire to it and pull the starting rope. If things go well, you should have a nice blue spark!

Will try to answer any questions-- Good luck, you can do it! Its not brain surgery!

Foggy
 
P1010767.JPG


I forgot to show how the ignition looks and how I ran the wires. ALSO--- I FORGOT TO MENTION THAT HOLE YOU DUG OUT OF THE POTTING, FILL IT WITH EPOXY OR YOUR CAULKING STUFF. And be sure that yellow wire is tight and not loose where it can hit the flywheel.

Again-- best of luck----


Foggy
 
Great job on the Bosch CDI ignition repair, too bad that I've thrown dozens of those in the trash can!

Are the caps not polarized?, in other words it makes no difference which yellow wire attaches to the terminals (the yellow ground wire or the yellow PC bus wire).
 
Great job on the Bosch CDI ignition repair, too bad that I've thrown dozens of those in the trash can!

Are the caps not polarized?, in other words it makes no difference which yellow wire attaches to the
terminals (the yellow ground wire or the yellow PC bus wire).

No, the capacitor is not polarized, just fasten the two wires, one each to a terminal... with solder of course. And too bad its too late to "dumpster dive" and retrieve those failed units. Now I want to be clear... many things can fail, I believe however the primary failure component is the capacitor. I have tested two so far, each suffering from this common fault. I have another ignition scheduled to arrive Saturday which I will test. I will be very surprised if the failure is a different component.

Those of you who need capacitors should check out EBay. I have described what type is needed previously in this thread, even posted a recommended capacitor where the seller will deliver 10 each for less than $7! See post 48 above.

Keep the faith, try the fix, the more people that do and find success will give the fix greater credibility!

Foggy
 
Brilliant Foggy!
I nearly started digging the potting off my ignition but glad I didn't as the board is way closer to the surface than I imagined. Fortunately I never throw anything away but this creates a problem in finding things!
Now I just need to find the capacitors on this side of the Atlantic to avoid the shipping.
 
Brilliant Foggy!
I nearly started digging the potting off my ignition but glad I didn't as the board is way closer to the surface than I imagined. Fortunately I never throw anything away but this creates a problem in finding things!
Now I just need to find the capacitors on this side of the Atlantic to avoid the shipping.

Just be careful what you order. Distributors include Mouser, Newark Electronic components, Digikey, Jameco Electronics.........BUT YOUR LEAST EXPENSIVE ROUTE IS TO FOLLOW THE PATH TO EBAY---[ got to have them pay me a commission!!! : - ) ]
 
HEY!!!! HOW DID YOU GUYS LIKE MY FINGERNAIL POLISH???? A little chipped?

That was Wifey's fingers. I had her hold a cold soldering iron near the wire I had soldered so I could take the picture.....HONEST GUYS---- : - )
 
HEY!!!! HOW DID YOU GUYS LIKE MY FINGERNAIL POLISH???? A little chipped?

That was Wifey's fingers. I had her hold a cold soldering iron near the wire I had soldered so I could take the picture.....HONEST GUYS---- : - )
Yeah yeah yeah !!! J/k
 
HEY!!!! HOW DID YOU GUYS LIKE MY FINGERNAIL POLISH???? A little chipped?

That was Wifey's fingers. I had her hold a cold soldering iron near the wire I had soldered so I could take the picture.....HONEST GUYS---- : - )
I saw that and was a little puzzled. But either way good fix. Lol
 
Just talked to a small shop owner about the 045&056. He knows a guy that has a few that doesn't run should I feel bad for buying these for little $$$$ ? If I can lol !!
 
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