A quick check of the parts books for the 400 to 405 confirmed that Bristol used the Lucas 031046 indicator switch shown on the bottom of the last page this is a mechanical electrical switch as opposed to the Lucas 31250 on offer through a few suppliers who say its interchangeable with the original unit, this could well be the case BUT its a vacuum operated unit so not a straight forward alternative fit, this unit is also shown in beölow.Lucas-Lighting-Direction-Indicator-Switch
The Bristol Owners & Drivers Association is a Member of the Federation of British Historic Vehicle Clubs. Bristol Owners & Drivers Association Ltd is a company limited by Guarantee of £1 per member.
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