MS661 -- No Spark

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Captain Bruce said:
The microswitch. The service info. states, test from the red to the black and look for 10 ohms. Thats from the solenoid plug, to the side plug. ? Those 2 wires (red/black) are both fine with zero resistance from the test terminals, THRU the solenoid connector, and all the way to the terminals ((spade & eyelet). Cross them to test? was a mystery. Page 65-66.
Click to expand...
The audible click of the switch is simply a mechanical action resulting from the control lever being placed into the start/choke position. This contact supplies voltage to a diode in the switch which temporarily activates the solenoid until the saw is running and under the control of the ECM. The switch will still make an audible click when activated by the control lever even if it is bad due to a faulty diode. The procedure for testing the diode/proper switch function is found on page 64.

BTW, a v3.0 upgrade kit from an honest dealer is around $120..., $117 and change from my area dealer through Bryan Equipment when I checked earlier in the thread.
 
Captain Bruce said:
No chance. If anything, it makes for a stronger magnetic field. Its put on the face of the magnets during production, to ward off corrosion.
Click to expand...
that yellow-ish paint over the magnets has very little to do with corrosion.
It's a thin electrical buffer... both magnets are very strong, and the individual fields overlap between the two without this coating.
without that coating blocking a portion of the magnetic field, the coil's computer gets confused...

My buddies Ebay 462 had that coating missing, everything tested great, but it would not create spark straight out of the box... the dealer claims they put a new, used flywheel in on a whim and a "why not, nothing else we've tried is working", and boom. it runs great now.
might be worth a second look...
 
Lawless crf said:
The m

Originally i had posted a thread about 661 no spark I thought thats where I was , if the micro switch clicks it good. The coil was $85 the solenoid was $45 the filter not sure it was already in the saw.
Click to expand...
Wow, thanks you your on-point insight. I see the charge for the kit is $130 total, and includes the orange filter. Since the switch is working mechanically, I'll put the carb back on, button up, and try to start. also noticed that when it does fire up, the bar/chain must be mounted to re-cal. Thanks again!
 
PogoInTheWoods said:
The audible click of the switch is simply a mechanical action resulting from the control lever being placed into the start/choke position. This contact supplies voltage to a diode in the switch which temporarily activates the solenoid until the saw is running and under the control of the ECM. The switch will still make an audible click when activated by the control lever even if it is bad due to a faulty diode. The procedure for testing the diode/proper switch function is found on page 64.

BTW, a v3.0 upgrade kit from an honest dealer is around $120..., $117 and change from my area dealer through Bryan Equipment when I checked earlier in the thread.
Click to expand...


Thanks Poge. I am printing those pages as I type.

Cost. Correct, was we originally discussed. It seems I was not charged, maybe because of the re-call. I didn't want to throw out numbers I could back up....if the charge happens, its your number spot on.

Whats your take on yellow coating has a purpose? I have looked at several flywheels on eBay. Seems most of them are working pull-offs with no coating at all??
 
Can you post pics of the wiring . Guy feeling says something ain't right in the harness. When I've had this level of trouble with an AT...
Its was a faulty ground. Yes I realize all the individual wires were continuity tested. If one is grounded when not intended to be or weakly weird stuff happens. Can you get another saw and swap back and forth to isolate "fails" ?
 
angelo c said:
Can you post pics of the wiring . Guy feeling says something ain't right in the harness. When I've had this level of trouble with an AT...
Its was a faulty ground. Yes I realize all the individual wires were continuity tested. If one is grounded when not intended to be or weakly weird stuff happens. Can you get another saw and swap back and forth to isolate "fails" ?
Click to expand...


Yes, BOTH wiring harnesses test OK for continuity, and my electician neighbour says, after visually inspecting BOTH sets of wires, that ALL connectors and wires are fine....and, grounding out would be limited to the areas where any wire has contact with the engine. The plastic slots that keep each wire in place, are non-conductive. Thanks for the input. Wiring is beyond good.
 
Captain Bruce said:
Yes, BOTH wiring harnesses test OK for continuity, and my electician neighbour says, after visually inspecting BOTH sets of wires, that ALL connectors and wires are fine....and, grounding out would be limited to the areas where any wire has contact with the engine. The plastic slots that keep each wire in place, are non-conductive. Thanks for the input. Wiring is beyond good.
Click to expand...

Continuity is good but, it won't tell you if there is a grounding issue. A switch should read either open or closed in relation to the source being switched. Single pole single throw switch that has ground as a source should read on its switched leg, open to ground in one position and shorted to ground in the other. Any other reading even if extremely high resistance will/could be problematic. This is a ground going into a micro controller or a micro processor, you aren't just making sure that you have a good ground. If the computer isn't seeing it's conditions being met, it will not operate. Honestly, this is pretty basic diag. It's a computer/chainsaw, treat the chainsaw stuff like a regular chainsaw and the computer stuff like a computer and it'll all work out.
 
Tom82 said:
Continuity is good but, it won't tell you if there is a grounding issue. A switch should read either open or closed in relation to the source being switched. Single pole single throw switch that has ground as a source should read on its switched leg, open to ground in one position and shorted to ground in the other. Any other reading even if extremely high resistance will/could be problematic. This is a ground going into a micro controller or a micro processor, you aren't just making sure that you have a good ground. If the computer isn't seeing it's conditions being met, it will not operate. Honestly, this is pretty basic diag. It's a computer/chainsaw, treat the chainsaw stuff like a regular chainsaw and the computer stuff like a computer and it'll all work out.
Click to expand...
^ what he said !!!! Lots of electricker talks ... I'm betting something isnt connected to the right something else. No disrespect meant. Maybe someone can catch it from some pics is my best suggestion. I had a 201tc one time that had a wire chafed. I scabbed in an appropriate replacement and it would NOT fire but tested proper. Changed the harness and all was good 2 go. You've already replaced about everything so ..
Leads me to think something ain't wheres it supposed to be.
Hope we get this figured out
 
angelo c said:
^ what he said !!!! Lots of electricker talks ... I'm betting something isnt connected to the right something else. No disrespect meant. Maybe someone can catch it from some pics is my best suggestion. I had a 201tc one time that had a wire chafed. I scabbed in an appropriate replacement and it would NOT fire but tested proper. Changed the harness and all was good 2 go. You've already replaced about everything so ..
Leads me to think something ain't wheres it supposed to be.
Hope we get this figured out
Click to expand...
Hey Chooch need help making a new avatar?
 
Tom82 said:
Continuity is good but, it won't tell you if there is a grounding issue. A switch should read either open or closed in relation to the source being switched. Single pole single throw switch that has ground as a source should read on its switched leg, open to ground in one position and shorted to ground in the other. Any other reading even if extremely high resistance will/could be problematic. This is a ground going into a micro controller or a micro processor, you aren't just making sure that you have a good ground. If the computer isn't seeing it's conditions being met, it will not operate. Honestly, this is pretty basic diag. It's a computer/chainsaw, treat the chainsaw stuff like a regular chainsaw and the computer stuff like a computer and it'll all work out.
Click to expand...
Switch test = zero. No readings at all.I'm replacing the switch next. Last electronic component.
 
angelo c said:
^ what he said !!!! Lots of electricker talks ... I'm betting something isnt connected to the right something else. No disrespect meant. Maybe someone can catch it from some pics is my best suggestion. I had a 201tc one time that had a wire chafed. I scabbed in an appropriate replacement and it would NOT fire but tested proper. Changed the harness and all was good 2 go. You've already replaced about everything so ..
Leads me to think something ain't wheres it supposed to be.
Hope we get this figured out
Click to expand...
The switch doesn't test good. I am replacing it and its the last electronic component, so it will bear out as the issue. Thanks for your help.
 

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