Hi all, I recently fitted NGK ZFR5N to my 73 Scamp 225. After going for a spin yesterday it felt like it was running on 5, I removed the leads one at a time and found number 4 made no difference. There was a spark jumping from the cap end of he wire to the wire when I disconnected that end. I've read that the washers should be removed from the plugs - I haven't done that yet. I was wondering what you guys think? I'm gonna pull the plugs and clean them today.

Chris.

You should remove the washers, but that should not make any difference in how the plug fires. Maybe you got a bad plug? Try swapping plugs between cylinders and see if it is the plug, or just pull the plug, ground the body of it, and crank the engine over to see if there is spark at the plug, then try another plug on the same wire.

Lou

_________________
Home of Slant6-powered fun machines

Well I pulled the plugs and removed the crush washers, 1 2 5 & 6 were very sooted and black, while 3 & 4 were normal to lean coloured. I'm sure it's firing on all 6 now, but confused about the plug readings

Glad it's firing on all 6 now. Soot: Probably rich mixture and/or combined with too much spark advance? Or, perhaps a weak coil or misadjusted reluctor gap? How smooth is the idle and how much does it drop when you put it in gear?

Lou

_________________
Home of Slant6-powered fun machines