MS661 -- No Spark

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I believe they were swapping coils at no charge even in no longer under warranty but, not all dealers are the same. Also, I believe some dealers were swapping out broken case halves as well because of a known flaw.

I've bought and installed a few of the coil kits. It's not just the coil, it's the solenoid. The early solenoids were made differently and were more likely to fail from vibration or dirty fuel. The new solenoids seem to be more robust, they also now recommend the orange filter (higher micron count to reduce debris from getting in the solenoid.
Copy that. I am convinced. Install it all.
As per an earlier comment from TOM82, re:wiring and the elusive fault(s).....I also bought a replacement wiring harness. I will magnify as I inspect, the entire harness, before installing...if necessary. While the carb is off, I will certainly put the present wiring under a microscope as well.

I may be getting ahead of myself, but when I grab the recoil and fire up first time..........I am seeing several schools of thought. Leave on choke for 90 sec...........make 5 cuts to load the saw.............I believe there is a YT video to make that crystal clear. This is a clients saw. I want it to go home, for good..
 
Copy that. I am convinced. Install it all.
As per an earlier comment from TOM82, re:wiring and the elusive fault(s).....I also bought a replacement wiring harness. I will magnify as I inspect, the entire harness, before installing...if necessary. While the carb is off, I will certainly put the present wiring under a microscope as well.

I may be getting ahead of myself, but when I grab the recoil and fire up first time..........I am seeing several schools of thought. Leave on choke for 90 sec...........make 5 cuts to load the saw.............I believe there is a YT video to make that crystal clear. This is a clients saw. I want it to go home, for good..
This is version 3 mtronic. It has a different calibration procedure than the previous version. 90 seconds on cold start and 5 cuts isn't how to calibrate this this setup.

I'll see if I can find the information for you.

Also, if you need a picture of the wiring for reference I can send you one. Mine is an arctic model so you just need to ignore the extra wires.
 
This is version 3 mtronic. It has a different calibration procedure than the previous version. 90 seconds on cold start and 5 cuts isn't how to calibrate this this setup.

I'll see if I can find the information for you.

Also, if you need a picture of the wiring for reference I can send you one. Mine is an arctic model so you just need to ignore the extra wires.
How can I provide my em?
 
Thats a like photo of the coil I have here......minor chaffing, and it hides inside the plastic channel in the housing.

On a seperate note, I rec'd the kit, from Stihl, via a local dealer location, in 3 days. They are readily available.
 
Hey guys dealing with same issue 661 cm #181954513 the carb housing was smashed fixed a few issues ran the saw a few times 10-16 cuts ran good started it today ran 5seconds and no spark found a knicked black wire from carb to slip on terminal, what was the out come the kit ? Here's some pictures of the wire .IMG_20200620_003119.jpg
 
Hey guys dealing with same issue 661 cm #181954513 the carb housing was smashed fixed a few issues ran the saw a few times 10-16 cuts ran good started it today ran 5seconds and no spark found a knicked black wire from carb to slip on terminal, what was the out come the kit ? Here's some pictures of the wire .View attachment 837037
I am SO grateful for this submission. I have a clients 661C here for minor repairs, and fell into the M-tronic worm-hole. So many fellows have chimed in......I have sincerely been taken to a new, and challenging, place in small engine mechanics. I bought the up-grade kit, as well as a wiring harness. When I inspected one from fleabay, it had damage just such as this?

I came to this with a frustrated attitude, and expectations.........these Guys waited for the chest-thumping to stop, and than said, Okay....so lets get your problem solved, and your saw. running.....Properly.

This is just 1 more reason to work the problem yourself, and when you ask for a favour, don' t expect results....be thankful when they come along.
 
I'm really just thinking about swapping it over swapping a coil swap in the carburetor I mean I had it running earlier today and it's running like a damn dream I got it home and started it up and had the issue, I checked it's got the black solenoid and the 1144 4701 coil, I'm going to fix this wire and look at the rest of the wire harness. It was kind of a interesting read to have some knowledgeable people not get to the point and say fix this. Good luck with your saw I'm going to get this f***** running again it's to mean not be eaten red woods 15926302458522976591246297656461.jpg
 
I just finished a 661 gen 3. Rear handle got sliced off at the a/f cover.
That red wire went into the channels that are located at the upper right side
and is retained along the back of the airbox.
Cant saw I’ve ever seen them in the switch.
 
Stihl 86 your rite these pics are in the process of removing carburetor and checking the wire harness the 4701 coil is the culprit 90%sure .
 
FYI. Remember terminal contact pressure comes into play also. Not just conductor continuity.
Especially @ 14000 rpms
I have been fooled by "It checked ok -- twice"
 
FYI. Remember terminal contact pressure comes into play also. Not just conductor continuity.
Especially @ 14000 rpms
I have been fooled by "It checked ok -- twice"
Can you elaborate on that contact pressure ? On the ignition control or the wire harness?
 
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