05-11-2020, 06:04 PM
Hi
The sender units for the later Smiths moving iron gauges are about 25 to 30 ohms for Full and about 2 or 3 ohms for Empty. Earlier ones were the same resistance but with Full and Empty values reversed. The two types are not readily interchangeable.
Moving iron gauges continued to be used up until the late 1950's, but often with senders having somewhat higher resistance. The MGA used about 70 to 80 ohms.
Later still (e.g. Austin Mini) thermal type gauges with a separate voltage stabiliser were brought in. These are slow responding and don't "dance" as the fuel moves about whilst driving.
The sender units for the later Smiths moving iron gauges are about 25 to 30 ohms for Full and about 2 or 3 ohms for Empty. Earlier ones were the same resistance but with Full and Empty values reversed. The two types are not readily interchangeable.
Moving iron gauges continued to be used up until the late 1950's, but often with senders having somewhat higher resistance. The MGA used about 70 to 80 ohms.
Later still (e.g. Austin Mini) thermal type gauges with a separate voltage stabiliser were brought in. These are slow responding and don't "dance" as the fuel moves about whilst driving.