A Question About Resistor Spark Plugs

[DanCorcoran]

My Craftsman 42cc engine specifies a Champion RCJ-7Y spark plug. The "R" indicates that this is a CJ-7Y plug (quite common) with a built-in resistor.

I've looked at 5 or 6 places here in Richmond and can't find one (they sell for about $2 online, but I'm too cheap to pay $6-10 shipping on a $2 plug). Does anyone know why a chainsaw would require a resistor spark plug? I've read that they reduce radio frequency interference with other electronics, but that doesn't make any sense in a chainsaw (there are no other electronic components, and it's unlikely you'd have a lot of radios playing in the vicinity of your chainsaw).

Does anyone know (I've Googled quite a bit and been unable to find a answer relating to chainsaws).

 

['bert]

you are correct about the radio interference, ditch the R plug and get on with your cutting.

 

[charly]

Some electronic ignitions systems , require a resistor plug to run properly. I remember reading something about it on "Spark plugs 411".

 

[DanCorcoran]

Yes, I read the article on Spark Plugs 411, but apparently it doesn't apply to chainsaws. So, no one knows why a chainsaw would be spec'd with a resistive plug?

 

[jebatty]

I was advised by my marine dealer that Canada law requires resistor plugs. The chainsaw may be spec'd for resistor plugs because it also is sold in Canada.

 

[raybonz]

My Craftsman 42cc engine specifies a Champion RCJ-7Y spark plug. The "R" indicates that this is a CJ-7Y plug (quite common) with a built-in resistor.

I've looked at 5 or 6 places here in Richmond and can't find one (they sell for about $2 online, but I'm too cheap to pay $6-10 shipping on a $2 plug). Does anyone know why a chainsaw would require a resistor spark plug? I've read that they reduce radio frequency interference with other electronics, but that doesn't make any sense in a chainsaw (there are no other electronic components, and it's unlikely you'd have a lot of radios playing in the vicinity of your chainsaw).

Does anyone know (I've Googled quite a bit and been unable to find a answer relating to chainsaws).

Dan I installed an e3 plug that I bought at HD in my snowblower and it seems to start much easier.. They are lifetime warranteed and cost a little more.. Here is a link to their site:

http://www.e3sparkplugs.com/

Ray

 

[ironpony]

it is so the chainsaw does not cause static on the boom box out in the woods while youre cutting
nothing more annoying than static on a radio station

 

[DanCorcoran]

Thanks, Ironpony, that's what I thought, too. (I figured it might also cause interference with my Pacemaker and my battery-powered bagel toaster that I keep with me in the woods).

Raybonz, you told me what I really needed to hear, though. I've seen those E3s at both Lowe's and HD, but didn't know whether to believe the hype on the package (since they cost about double, I figured it might be snake oil). I'll get one and try it out...thanks.