Stihl 041 Rebuilt - Running too rich

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I say with quiet confidence, that brown ATOM CDI from Australia is your issue. That’s the last place it should be mounted too.
Ok, I’m confident in your confidence!

a few posts back I sent a picture of points and condenser from Little Red Barn. Is that an ok source for that? Or do you have a recommendation for points? Many thanks!
 
Do you have a multi meter? Wouldn’t hurt to check the primary and secondary windings on it. At a guess you’re looking for around 1ohm on primary and 7kohms on secondary. Both readings should be stable and repeatable.
I do have one. Never checked a coil but will see if I can make sense of it when I get the flywheel off. Thanks for the idea.
 
Ok, so I got the flywheel off today. Here’s what it looks like under there. I’m going to have to make sure I have good connectors and crumpets when putting this back together and rewiring. I hate to have to splice wires.
Based on the IPL also attached, it looks like the red wire will go away and I’ll have 3 wires attached to condenser: 1)Points; 2) Coil; and 3) Kill switch.
Regarding opening of the points, I do not see a lobe on the crank. How does that work?
D711E067-D5FB-4B45-B1BA-02FAA86BE046.jpegCCD0FE0B-D563-4818-AC66-3346823966B5.jpegB36AC526-537A-4261-8D33-24815341A111.jpegB30874E4-3ECA-40C3-A30F-35031E0E7032.jpeg
 

Attachments

  • EAD5552C-A9DF-4770-A9D7-3CEADFD118E8.jpeg
    EAD5552C-A9DF-4770-A9D7-3CEADFD118E8.jpeg
    1.5 MB
  • E121D87F-5885-4C90-95BF-44335E2316D7.jpeg
    E121D87F-5885-4C90-95BF-44335E2316D7.jpeg
    305.4 KB
Do you have a multi meter? Wouldn’t hurt to check the primary and secondary windings on it. At a guess you’re looking for around 1ohm on primary and 7kohms on secondary. Both readings should be stable and repeatable.
I attempted to measure the resistance. I saw 2.5 to 3 ohms in the primary, and 5-5.5k secondary. Assuming I was doing it right. Secondary test was done to spark plug wire and coil armature (using 20k ohm scale), primary to the white wire from coil and the coil armature (using 200 ohm scale) I’ll note that the numbers really jumped around when I slightly moved test lead on the armature.

My primary side is showing higher resistance than your estimate of 1 ohm. Hmm…
 
Touch MM leads together before test to get a true 0 reading.
Might be .2-.3 ohms due to lead resistance.
Good tip! About 0.4 or 0.5 ohms when touching leads together (200 ohm scale). About 2.5 ohms on primary. So if 0.5 is atttributed to the meter, then resistance of about 2 ohms?
 
Yep they are all good readings. Nice to see you still have the original capacitor and points cover. Doesn’t hurt to test the capacitor. Check out your points too, though they are probably unusable as the wiper block is probably worn away with years of use without any grease. Cool none the less!
 
Yep they are all good readings. Nice to see you still have the original capacitor and points cover. Doesn’t hurt to test the capacitor. Check out your points too, though they are probably unusable as the wiper block is probably worn away with years of use without any grease. Cool none the less!
How would I go about checking the points? Is the wiper block the piece that contacts the love to push the contact open? I see that should be part of the new points (which were supposed to have been delivered Feb 1 but still haven’t shipped). How often should those be greased?

And my multimeter measures capacitance. Any idea what spec on that should be? Would you go ahead and replace both right now or if the capacitor measures ok then leave it? (I’m already wondering how I will get it out…)
 
This should help, I did this video a while ago. To get the condenser out you need to remove the stator and tap it out from the front by pushing in the back of it. It’s just a press fit.

As for grease, it depends how much it’s used. For home owner use, each service - generally yearly.

 
The ATOM CDI Module you have is mounted it the worst possible location, perhaps other than on the muffler.

Those modules with not take the heat that is coming from the cylinder head. You should move it to some spot that will not heat it up.

As far as the flooding goes, I'm guessing that as the heat from the engine heats up the fuel and air in the fuel tank, the pressure created forces fuel into the carb, over-powering the needle and flooding the engine.
 
Good morning all. :)
I have read this entire thread. A lot of things have been done and great suggestions made by VER. Earlier in the thread you mentioned that it has tremendous vibration due to a bent crank shaft. Just wondering why nobody has suggested replacing the crank shaft? The vibration is pretty bad as you had to stop and tighten the top cowl screw several times while sawing in the video. I feel that nothing will work properly with that much vibration. Vibration at high speed = resonance or harmonics. That alone can effect the operation of the carburetor not to mention the operation of the points. Maybe that is why someone went to the CDI? My second concern is what caused the original damage to the piston with the welded ring? Running to lean and overheated maybe? Straight fuel with no mix maybe? Foreign matter entering the intake? Something had to cause that. I'm just curious. These are just thoughts that entered my mind while reading the thread. Keep us posted. I really enjoyed reading your progress. And Patrick, your probably snowed and iced in like we are here in KY. :cool: Have a great weekend. OT
 

Latest posts

Back
Top