Difference in spark plugs for Fd-12

[Hogie22]

I was looking at my the plugs in the FD-12 I recently purchased and noticed the plugs are J6J.
I ordered some tune up parts from marineengine and it looks like I have new J6C plugs.
Are they similar?

I can't remember if they are a cross reference plug that popped up when I entered J6J or if I accidently ordered the wrong ones.

 

[Rick.]

Re: Difference in spark plugs for Fd-12

J6J isn't made anymore. J6C is the correct substitute. Rick.

 

[F_R]

Re: Difference in spark plugs for Fd-12

That is correct. FYI, the second "J" means a two-cycle plug. That means the side electrode only went half way across the center electrode. That was supposed to help prevent gap-bridging. It also presents a sharp edge for the spark to jump to, which doesn't require as high a voltage as a flat surface does. In other words, it will fire with a weaker spark.

If you care enough, you can make your new ones to be a "J" by filing the side electrode half way back.

The new "C" means copper. That's spark plug marketing talk for BS.