First: Try a new (or really decent) battery and make sure ALL connections are secure and none frayed to earth in another place. Check all fuses, particularly engine management system. Check output from generator at tickover and high revving. Check standing current over a period of parking up time. Standing voltage at battery ought to be minimum of 12+ volts, tickover voltage should be 14+ volts. Connect leads to battery terminal, rev up gently and gradually increase the revs while keeping an eye on voltage readings at battery. Ensure output from generator is steady and not fluctuating throughout rev range. Check all fuses on engine management systems. If nothing untoward found - take it to a Ford agent with diagnostic setup, and a well wised up auto electrician - he may be able to tell you what is the cause so that you can fix it yourself - otherwise pay up for his expertise and get him to fix it. Of course, there could be a bit of stubborn muck in the carb being sucked up and down but not blown OUT. Clean the carb inside and out, give it a blow with a high pressure hose. Make sure no splits in any other associated hoses. Remove, clean and replace all jets. If battery supply is low or fluctuating a lot it could be one diode of the three fitted to the phases of the generator has failed. Answer from Tallyho.
Eddie (Tallyho) Broom
April 2010
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