I hope it wasn't due to any wires metling.... Hopefully just a lose connection perhaps the earth to the engine/ chassis. I had a problem with my earth whihc mad teh starter run slower, and even cause teh fat wire to start smoking as it was getting too hot, but after finding a better earthpoint on the clutch housing the starter was faster and teh engine ran better,
Just had a call, mother & baby doing fine, it was a connection for the tachometer which was causing the problem. Think it was connected to the wrong side of the coil. Baby now screaming it's head off, looks like he might make it, but still 3 to 1 against.