Saving Old Seagulls

I have been having problems with D16 sparkplug failures in my 'gulls and other old engines,Lister,Bamford etc. :cry: Even brand new D16 plugs last no time until the insulator cracks or the spark fails,has anyone else ever experienced similar problems? I find the NGK AB6 a much better plug as the old...

Hi there everyone, I am new to this site but not to British Seagulls!! :) I have only two 'gulls at the moment,I once had 5 and a British Anzani. My present 'gulls are 1968 SPCL and 1972 WSPC. Both are running well and sound just like they should! Although I must say the longshaft model is the quiet...