Stihl 026 dying after running fine for 5-10 mins
- Thread starter johnbinsc
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johnbinsc
ArboristSite Lurker
Hi again experts!
I'm finally getting back to you with an update.
1) My spark plug is an Autolite 2984. The electrodes look good, with a light tan coating.
2) The rest of the wiring looks OK, although I did not take off the recoil starter cover thing to look at the wires all the way to the coil.
3) I did the spark test cold and hot by removing the plug and wrapping a bit of bare copper wire around the plug threads and the metal stud on top of the cylinder head. I saw a spark both cold and hot (i.e. after I couldn't restart the saw). My impression is that it is a pretty weak spark in both situations. For example, I could not see the spark unless I was in complete darkness. From other experiences I have had checking spark in the past (probably on cars), I'm thinking that I should be able to see the spark on the plug tip in shaded daylight, but I'm open to hearing your wisdom on this.
Thanks! --John
I'm finally getting back to you with an update.
1) My spark plug is an Autolite 2984. The electrodes look good, with a light tan coating.
2) The rest of the wiring looks OK, although I did not take off the recoil starter cover thing to look at the wires all the way to the coil.
3) I did the spark test cold and hot by removing the plug and wrapping a bit of bare copper wire around the plug threads and the metal stud on top of the cylinder head. I saw a spark both cold and hot (i.e. after I couldn't restart the saw). My impression is that it is a pretty weak spark in both situations. For example, I could not see the spark unless I was in complete darkness. From other experiences I have had checking spark in the past (probably on cars), I'm thinking that I should be able to see the spark on the plug tip in shaded daylight, but I'm open to hearing your wisdom on this.
Thanks! --John
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Not real familiar with Autolite plugs- I think if its a copper one it is R for resistor type and that is where you want to be.
Some coils (not sure if it applies to 026) cannot handle non resistor plugs and it cooks the coils. Which is why I asked the question.
johnbinsc
ArboristSite Lurker
Several online listings indicate the Autolite 2984 as a copper core resistor,
and an online plug crossreference matches it to the NGK BPMR7A, which is what the parts list specifies as the OEM plug.
Online, one guy said the Autolite 2984 was the OEM plug in his Stihl 026.
So this might be the original spark plug.
I doubt it is bad, but it is easy and cheap to replace.
and an online plug crossreference matches it to the NGK BPMR7A, which is what the parts list specifies as the OEM plug.
Online, one guy said the Autolite 2984 was the OEM plug in his Stihl 026.
So this might be the original spark plug.
I doubt it is bad, but it is easy and cheap to replace.
You dont need a resistor plugg, I only use that on saws with m- tronic or Auto-tune. Try a new coil and a new plug without R. This is a good one.https://www.trodo.se/tandstift-denso-w22mp-u?utm_source=google&utm_medium=cpc&gad_source=1&gbraid=0AAAAADJzNp4ZhhhLhdYZo7xxFkRyvEzgu&gclid=EAIaIQobChMIkr65wIGqiAMVbE-RBR2l0B3REAQYAiABEgIHK_D_BwE
