12-06-2024, 10:55 AM
Hi again Denis
I have now had a chance to take a more detailed look.
Your problems seem to centre on an erratic fuel gauge. This is supplied from the auxiliary 25 amp fuse, along with the stop lamp and the indicator switch common point. The gauge also has a connection to ground via the cutout ground, and a connection to the tank sender. The return from the tank (originally rubber mounted) is via the copper petrol pipe to the petrol pump and thence the engine block.
Some questions:
Is the auxiliary fuse and its holder clean and tight ?
Is the copper petrol pump intact all the way to the petrol pump, i.e. no sections of rubber hose, plasic filters etc ?
Is the ground wire from the E terminal of the cutout present and working effectively ?
Is the stop lamp grounded effectively to the bodywork, i.e. does it have a dedicated wire and not relying on contact from the boot lid to the body ?
As you can see, I still feel that interaction between gauge and lighting is related to a poor ground somewhere. It may be prudent to remove ground connections and check there isn't paint or corrosion underneath.
Some other observations which are probably unrelated:
The original starter wiring has two thick cables directly from the starter motor (live stud and grounded fixing bolt) to the battery. Do you still have both of these, or has the ground side been replaced by the one to the cylinder head via the battery box ?
Capacitor type suppressors should not have their live wire lengthened beyond the supplied few inches, as this reduces their effectiveness. In my experience, HT plug top suppressors (5 kilohms) are much more effective at preventing misbehaviour of electronic flashers, it is the interference radiated form the HT leads that is dominant.
I have now had a chance to take a more detailed look.
Your problems seem to centre on an erratic fuel gauge. This is supplied from the auxiliary 25 amp fuse, along with the stop lamp and the indicator switch common point. The gauge also has a connection to ground via the cutout ground, and a connection to the tank sender. The return from the tank (originally rubber mounted) is via the copper petrol pipe to the petrol pump and thence the engine block.
Some questions:
Is the auxiliary fuse and its holder clean and tight ?
Is the copper petrol pump intact all the way to the petrol pump, i.e. no sections of rubber hose, plasic filters etc ?
Is the ground wire from the E terminal of the cutout present and working effectively ?
Is the stop lamp grounded effectively to the bodywork, i.e. does it have a dedicated wire and not relying on contact from the boot lid to the body ?
As you can see, I still feel that interaction between gauge and lighting is related to a poor ground somewhere. It may be prudent to remove ground connections and check there isn't paint or corrosion underneath.
Some other observations which are probably unrelated:
The original starter wiring has two thick cables directly from the starter motor (live stud and grounded fixing bolt) to the battery. Do you still have both of these, or has the ground side been replaced by the one to the cylinder head via the battery box ?
Capacitor type suppressors should not have their live wire lengthened beyond the supplied few inches, as this reduces their effectiveness. In my experience, HT plug top suppressors (5 kilohms) are much more effective at preventing misbehaviour of electronic flashers, it is the interference radiated form the HT leads that is dominant.