I have a Zenoah G-26 gaas engine for an airplane. I snapped the sprak plug today. (How is not important..) Anyway, I went to a few auto motive stores, home depot and a small engine shop. No one has the RZ7C spark plug that came with my motor. The person at the small engine shop said that it must by a type o on the plug becasue he has been doing this for 20 years and has never heard of a "Z" in the part number. So I went home to reference my zenoah manual and it also stated the same RZ7C spark plug, I then called my local hobby shop, they carey spark plugs, but again have never heard of the "Z" in the plug. I found another spark plug that has a R for resistor in the number, and fits well, will this be ok to use, and where can i find the proper spark plug?
slo

The only other 10mm resistor spark plug I know of is made by Denso, but is about 1/2 inch longer..The Champion is a relatively new addition...If you have another 10mm resistor spark plug I would like to know the brand...The Champions are available from BH Hanson in Las Vegas.. Horizon Hobbies has them for more $$..They like to add to the retail price because they think people can't get things elsewhere...Horizon price is $10.50..
sparkplugs.com has them for about $5.00...
Any other 10mm spark plug with an "R" in the number will be OK, but might not have the thread length of the RZ7C and the Denso...
The NGK CM6 will work, but is not resistor and has shorter threads..The red spark plug boot is made for the RZ7C and won't fit the CM6 very well...

CH Electronics has them is stock $3.95. Won't do you much good this weekend, but.............