IMPROVING AUSTIN SEVEN ELECTRICS

The following article is a précis of comments made during a Technical Forum of the Dorset Austin 7 Club in January 2006.  The club and its members cannot be held responsible for the accuracy of any information given nor any costs, damages or accidents arising out of using this article.

Battery and Starter

• Ensure the earth bolts onto bare metal using a star washer and/or locking nut.

• Use Vaseline around earth bolts.

• Ensure correct size of connector used on battery – different for positive and negative terminal posts.

• Use Vaseline on battery clamps.

• Solder the main battery leads into the clamps, even if there is a screw clamped connector.

• Ensure heavy duty double insulation on live feed to starter

• Keep the starter switch clean of oil to prevent fire.

• Use battery isolator switch for safety – consider using on earth connexion as all parts at same potential – very compact earth bolt isolator available from Tim Hodgekiss.  Important Note:  Never operate isolator with engine running as the unregulated dynamo output will blow electrical parts such as bulbs.

Cables and Wiring:

• Route cables using clips and use grommets where wires go through holes in the bodywork.

• Watch out for Box Saloon reproduction cable saddles – they are very weak

• Avoid old armoured cable which may short on its own armouring.

• Use of shrink wrap on armoured cable to close off armouring.

• Use shrink wrap or self amalgamating tape on the ends of cable lugs and ensure they are properly soldered.

• Use maximum gauge cable to prevent voltage drop

• Good cable looms are available from Wiring Harness Company and they will put extras in for you.  Seven Workshop looms now have provision for flashers (?)

• Commercial scrap yards are good source of long cable lengths in a multitude of colours

• If using single conductors aim for neatness and avoid vibration

• Can use black cloth tape for taping together wires

• On specials etc. can use spiral wrap, pvc tape and flexible tube and even 7 core trailer cable

  Better Earth Connections

• Run extra earth strap from engine to chassis or even back to earth bolt

• Make sure headlights have a separate earth back to chassis

• Ensure cut-out mounting bolts are on clean metal with star washers

  Connections

• Use extra junction blocks to save trying to stuff too many wires into each hole

• Use quality extra junction boxes if unavoidable on ammeter or where insufficient space under grub screws

• Replacement grub screws for switch panels are 0 BA and obtainable from model supplies but will have hexagon slot

• Check the tightness of all screw connectors behind the dash panel including the ammeter

• Always be generous on cabling switch panels to allow easy removal and connection

• Crimped connections are unreliable

  Lights

• Always ensure good earths

• Use halogen bulbs and re-silver reflectors (Willy McKenzie does conversion kits with new reflectors)

• 12 volt gives same watts for half the current – use Honda Gold Wing battery when space tight(?)

  Flashers

• Essential for modern traffic

• Can be motorcycle type from Brit Bits etc or chopper side lights from same at £7.50 each or motorcycle Dinky Winkas(may be too small) or Model A Ford Vintique rear lights from SVC(Stafford Vehicle Components)  or just original lamps modified to take orange bulbs.

• Ray Fisher motorcycles stock 6V flashers – avoid old thermal click-clack types

• SVC stock clockwork cancelling flasher switch but slightly crude and expensive

• Tim Hodgkiss does range of  indicator switches

• Use of Maplin 6V or 12V buzzer with diodes across switch output

• Use of low wattage pilot bulb across indicator switch output

• A30/35 cars have a good indicator switch

  Special Interest Items

• Use of mini gas torches for soldering

• Use of surplus low voltage down-lighter bulbs using plug in base from RS

• Use of same items to provide high efficiency reflectors by using Dremel type diamond cutting wheel to remove lamp and provide aperture for 21watt orange capsule lampholder for installation in existing sidelights etc.

• The best quality electrical components are seen at aero jumble sales

With very many thanks to Phil Whitter (DA7C) for providing these notes as well as chairing a very lively and interesting evening.