Ime very pleased for you I know first hand what it feels like, it drives you mad I was waking up in the middle of the night trying to solve the problem on horsegut
I agree it sounds like you are losing spark after the first bang I know you have a mag but ian and I had the same symptoms on horsegut drove us mad for three weeks turned out we had one good spark then crap ones =we had wired the condenser up wrong.
Its not a rolls Royce its a tractor built on a budget if it was good enough for Harry Ferguson its good enough for me and
already its got more paint on than an original wheel horse or gutbrod
