13-06-2018, 03:56 PM
(13-06-2018, 02:09 PM)wallacelondon1@btinternet.com Wrote: I have a 7 Special with a relatively tuned engine.
I'm using NGK B6H S plugs, but after about 15 minutes it drops to two or less. On removal they are wet with fuel.
Do I need different plugs, or are my gaps wrong. John Wallace 07770 410 010
Hi John,
A little more information helps diagnose what's going on - the head, carbs and ignition details or a photo might help here?
B6HS are 14mm short reach plugs so I'm guessing you've one of the later cast iron heads? According to my information they should work in that head and normal gaps of 20 to 25 thou should be fine if your coil is working. Have you tried swopping them between cylinders and is it always the same pots that foul? Are you sure it's fuel that's fouling them or oil and then unburnt fuel? B5HS are a little hotter and could help IF you're oily.
Dave