Resistor spark plug question

wysiwyg · Dec 19, 2006

My Poulan Pro 4218AVHD came with a champion RCJ7Y spark plug, and this is specifically what the manual says should replace it. The problem is that I can't find this plug anywhere locally, only CJ7Y (no R), and if I go over the internet they cost $7+ each w/ shipping. The guy at Ace (not a Poulan dealer) said that resistor plugs aren't "required" for small 2 stroke engines, but I've also read that newer saws actually require resistor plugs to work correctly. Is there a consensus on this? If I need the R plug, can anyone provide a cross reference to another brand that I could look for? Thanks in advance.

blis · Dec 19, 2006

should work with non-resistor plug.. its mostly meant for cars and such that have alot of electronics that might get problems with non-shielded plugs...

ray benson · Dec 19, 2006

Here is one cross-reference chart. If it calls for a resistor plug why chance messing something up?
http://www.acresinternet.com/cscc.n...e39d1995d7ddc91588256e0c00029d0f?OpenDocument

1wildthing · Dec 19, 2006

The resistor plug will not interfere with radio reception in the area, non-resistor plugs will. There is no other difference. You will never tell a difference in your saw. This is the reason that many places do not carry the "r" plugs for small engine apps.

ShoerFast · Dec 19, 2006

If you ware a headset while running your saw, you will find out real soon what the "R" stands for, especially if your an AM fan.

Urbicide · Dec 19, 2006

ShoerFast said:
If you ware a headset while running your saw, you will find out real soon what the "R" stands for, especially if your an AM fan.

Exactly. Resistor spark plugs were designed to reduce radio frequency interference (RFI) primarily on AM frequencies. FM is not as critical except on weak signals. The tape head in a cassette player is also susceptible to the pulse noise created by spark plugs firing (as compared to alternator whine, a whole different kettle of fish).