06-11-2020, 04:58 PM
Hi Paul
There is undoubtedly some connection between the gauge numbering and whether it uses the early or late system, but I don't have any reliable data.
You can bench test a gauge in the following way:
Connect a 6V battery to the B (Battery) terminal, and the other terminal of the battery to the metal casing of the gauge (normally this is earthed via the dashboard).
With nothing (open circuit) connected to the T (Tank) terminal, the early gauge should read Empty. Now connect a short circuit wire from T to the casing, the early gauge should then read Full.
If you get Full with an open circuit and Empty with a short circuit, you have a late gauge.
These gauges draw less than half an amp, so the testing battery doesn't need to be anywhere near heavy duty and thin connecting wires are OK.
There is undoubtedly some connection between the gauge numbering and whether it uses the early or late system, but I don't have any reliable data.
You can bench test a gauge in the following way:
Connect a 6V battery to the B (Battery) terminal, and the other terminal of the battery to the metal casing of the gauge (normally this is earthed via the dashboard).
With nothing (open circuit) connected to the T (Tank) terminal, the early gauge should read Empty. Now connect a short circuit wire from T to the casing, the early gauge should then read Full.
If you get Full with an open circuit and Empty with a short circuit, you have a late gauge.
These gauges draw less than half an amp, so the testing battery doesn't need to be anywhere near heavy duty and thin connecting wires are OK.