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  #1   IP: 74.176.137.67
Old December 21st, 2010, 05:46 PM
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Default Poulan still won't start

My Poulan 2450 chainsaw stopped cranking today. Ran it 5-6 times earlier this year with no problems at all. Now it will not even sound like it might crank. No strong gas smell (as with flooding), choke working OK.

I jumped to a diagnosis that proved to be wrong: Replaced spark plug and rebuilt carb (the carb WAS nasty, by the way). Still will not start (sounds exactly like it did before "repairs".)

There was gas in the carb, so I have to believe that spark is the problem, but don't know how to verify that.

1. How do I verify spark?
2. If there's no spark, what then?

Thanks for sharing your experience
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  #2   IP: 72.38.193.87
Old December 21st, 2010, 07:56 PM
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Remove spark plug. Plug back into wire. Make sure threaded end is touching metal of head. Pull cord and watch for spark.
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  #3   IP: 74.176.137.67
Old December 22nd, 2010, 05:32 AM
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Default No spark!

No spark, Joed.

What's the next troubleshooting step?
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  #4   IP: 173.79.244.216
Old December 22nd, 2010, 07:37 AM
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Check that the coil resistance is a few kiloohms. The high voltage secondary winding may be open or shorted to the armature.

Last edited by SayWhat? : December 22nd, 2010 at 07:52 AM.
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  #5   IP: 207.35.6.2
Old December 22nd, 2010, 09:38 AM
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Check the kill switch, kill switch wriing(could be shorted to ground).

Different plug should also be tried. Have someone you don't like hold the spark wire while you pull the cord.

Last edited by joed : December 22nd, 2010 at 09:40 AM.
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  #6   IP: 74.176.137.67
Old December 22nd, 2010, 11:53 AM
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Default Kill switch and coil

I thought of the kill switch just as I sat down to the computer. I hope it's that as I don't know s from Shinola about coils... though I do have a multitester.

thanks, I'll let you know what happens.
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  #7   IP: 142.167.1.217
Old December 24th, 2010, 04:27 AM
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Yeh disconnect kill switch, dont bother testing the coil, it either farts or it dont, I havent worked on too many chain saws but I had a husky here last summer & the wire was route down beside the carb, & somhow I think it was during factory assembly, the wire got pinched behind the carb, so now picture this, Unit will not start, so put a dab of fuel in plug hole, no start, disconnect kill switch, no start, remove secondary wire, start, well you know how tight everything is in there, I could'nt see where the wire was routed, & had no Idea it got jammmed between carb & intake, so imagine my confusion, knowing everything iI did was rite, I scratched my head for a couple hrs, finally called a buddy who works for an athourized dealer, well he lead to the problem, & professed the first time he ran into it, it took him for a loop too.
Not saying this is the problem, but dont just look at the switch, check wiring also.
MJ
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  #8   IP: 74.176.137.67
Old January 1st, 2011, 11:21 AM
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Default Strange kill switch

Mr. Cormier,

Finally got around to going back into the chain saw. Removed air cleaner assy. (again), lifted kill switch out without disconnecting leads and did continuity check. Got 100% continuity between the leads whether the switch was set to run or stop.

Pulled the leads off the kill switch and tested the kill switch by itself... got a strange result (strange to me anyway). Got no continuity when the switch was set to start/run ( "I" symbol), and got continuity when set to off ("0" symbol). Bad kill switch, huh?

Do I even need to look any further?

thanks for the help.
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  #9   IP: 72.38.193.87
Old January 1st, 2011, 01:27 PM
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Tape up the two ends of the kill switch and pull the plug. Make sure the plug is touching the metal head an pull the cord. If the kill switch was the problem you should see spark. I would say try and start it, but hen how would you stop it?
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  #10   IP: 142.167.1.217
Old January 2nd, 2011, 12:58 AM
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Kill switch is ok, There is nothing strange with your second reading, you see, the start/ run switch does not turn on any power source, so when you switch to off, all that happens is you cause a dead short from the coil secondary to ground which stops the coil from energizing.
Do a continuity test from 1 wire to engine block then the other wire, only 1 wire should show continuity, the other should show open, if they are both showing a full reading its the coil secondary wire that has shorted, & not a bad coil. At this point you would have to get to the coil, disconnect the wire & find out where it shorted to ground
If only 1 shows continuity its coil failure.
Good Luck
MJ

Last edited by MJ CORMIER : January 2nd, 2011 at 01:00 AM.
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