A friend asked me to fix his Craftsman saw. He said it wouldn't start. It's a newer one (I believe a Poulan) Model 358.350880. When I check for spark using a tester with a light bulb in it it shows spark but with a different type of tester that actually sparks, no spark. No spark when plug is grounded either. Got a new plug, no spark. Got another plug no spark. Checked all wires from kill switch to ignition, all fine. Checked kill switch, that's working. Disconnected the wires from kill switch to I.M. No spark. So I thought it was the ignition module. Got a new one and a flywheel in a kit and installed. Same symptoms as before. I don't know what to try next. If the I.M. isn't getting a good ground to the saw could this be the cause? I don't know. I'm hoping someone has experienced something like this and can help. Any help would be appreciated.
Craftsman 42cc spark issues
- Thread starter Ganz
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Little Al
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If you have an Avo ( test meter) check you have continuity from crankcase/cylinder to lamination"s on the coil make sure the faces of the lugs the coil bolts to are clean if you turn the flywheel with coil bolts slack when the magnets reach the coil doe"s it snap the coil onto the flywheel?are you setting the air gap (coil to flywheel) 10/12thou, business card or slightly less gap, if all is good you should have a spark,some electronic coils don"t give a very strong spark at cranking speed but usually if you can see a spark at the plug electrodes most will pop or run If you have a spark & fuel then i would think its down to the timing Check to see if the old & new flywheel key way is in the same position in regard to the magnets, are the coil laminations the same on both coils? bit shots in the dark without actually seeing the bits & pieces
Thanks for your reply. I will check for continuity from the lams to cylinder. Air gap was set correct. I'll have to double check the flywheel. I thought it checked out but I'll look again. I just don't understand how I get spark checking one way but not two other ways. There is no fire for sure when I try to start it. I have yet to get a pop out of it even putting a shot of carb cleaner into the carb. This one just has me stumped. These motors aren't that fricken hard to make run.
Plugs have been known to fail, too. Esp. "torch". One of the first "won't start" things to do is to swap for a known-good plug.
Just because you have voltage to the plug doesn't mean current through it. Best tester for that is an inline one, with a neon tube inside plastic. You'll see if it's conducting that way, the important thing.
Just because you have voltage to the plug doesn't mean current through it. Best tester for that is an inline one, with a neon tube inside plastic. You'll see if it's conducting that way, the important thing.
There is no reason it shouldn't spark from everything you mentioned. I would replace the wiring. It's possible there is an internal break in one. I wouldn't rely on a contintuity test either. If only one strand is good, it will show contintuity, but may not be a good enough ground. Possibly make up another secondary ground wire to the module.
I tested with my inline tester that has exactly that. You can adjust the gap on it and watch the spark inside the tube. No spark. I thought about grounding the coil somewhere else but I've yet to locate a good spot. The whole saw is plastic. I will take your advice and make up some new wires to see if that works to. They do have continuity now but who knows. Probably won't get to it till the weekend, this week is jam packed. I really appreciate the help. I hate to give the saw back to him and admit defeat. Especially after I put money into it. I'll report back soon. I forgot to mention, The orig plug was a torch. I tried a brand new Champion and an Autolite, still no flame. They do spark on my other saws.
Little Al
Addicted to ArboristSite
Do you have a made up lead with a crocodile clip on each end? connect 1 end to coil laminations the other to a cylinder fin, disconnect the kill switch wire from the coil & see what result you get. do you know if the replacement coil is good? have you tried using new coil /old flywheel, new flywheel /old coil? closing plug gap down to 16 thou or so, It"s all a bit of a totter around in the dark syndrome, if the coil is good , earth is good fly wheel magnets & timing correct, as my Grandad used to say it"s got to work there"s nothing to stop it spark wise that is.
Are you sure you posted the correct model number? When I looked that model's IPL on Searpartdirect I got a copyright date of 4/1976. It show it having point style ignition system and coil with a separate high tension lead. If your are re-using the old high tension lead it probably got a break in it.
The 358 at start of model number does indicates that it is a Poulan/Weedeater or a Beaird - Poulan, Inc unit depending on it age.
The 358 at start of model number does indicates that it is a Poulan/Weedeater or a Beaird - Poulan, Inc unit depending on it age.
That is the Model # on the saw. I know I found the same thing with it being an old saw model #. The other info on the tag is: Family/Disp: 9PWES.0424CN/42cc and Serial # 09124D400265 06:13. It's a newer saw for sure. My friend said he bought it new a few years ago. I took the part # off the old ign module to find the correct parts. What is the high tension lead you refer to? The wires that go to the kill switch?
oppps. Mixing in my electrical terms from AC electric. High tension is the high volt lead in your case the plug wire. If it is a newer then most likely the coil came with a new cemented in place.
When went back to Sears Parts I downloaded both owners manuals to see what the differences were. My comment "STUPID" to the same model number for two different saws.(just my opinion). What you have is basically Poulan Pro PP4218AVX in Sears Craftsman colors.
Here is a link to the owners manual with parts list.
http://www.managemylife.com/mmh/pd_download/lis_pdf/OWNM/L0807186.pdf
When went back to Sears Parts I downloaded both owners manuals to see what the differences were. My comment "STUPID" to the same model number for two different saws.(just my opinion). What you have is basically Poulan Pro PP4218AVX in Sears Craftsman colors.
Here is a link to the owners manual with parts list.
http://www.managemylife.com/mmh/pd_download/lis_pdf/OWNM/L0807186.pdf
have you tried the alligator clips and wire as little al in the post above mentioned? if not you need to, will tell you if a grounding problem. we also use a jumper wire with larger clips to snap onto the plug base to a ground area. spin the flywheel over with drill.
Not yet. I haven't had time for some "garage therapy" yet. But I did do the trick with the plug and the wire to ground it. Tried spinning with drill too. This weekend for sure I should get at it.. I did check that grounding clip. It seems to have continuity to the case. I thought maybe the tab was cracked or something.
sounds like your on the right track. that tab will break from vibration or screws may loosen up in bottom of case.
you have to remove the cyl. to do that. check for spark with jumper wires first. if it is broke its usually at the bend behind the flywheel.
Well guys I just want to thank you for helping me with this. I didn't really do a lot different but you all help to confirm what I thought. The ign module wasn't getting a good enough ground. Once I messed around with it enough to get a good reading on my meter I had good spark. Needless to say I'm a happy camper. I just wanted this problem off my bench. It's miller time, thanks again.
