This blog, in addition to the usual maintenance details for classic mini cars, an attempt is made to explain the "whys" and "wherefores" of the various jobs.

Sunday, 11 October 2009

Waterproofing the Ignition System

Owing to the "East to West" arrangement of the engine, the ignition system on earlier models receives less protection against water and spray which may enter through the front grille, than is the case with cars which have a more conventional layout. If a water-splash is taken at too high a speed,for example, the whole system may be doused, and even heavy rain may cause misfiring or complete cutting-out.
B.L.M.C. dealers supply a special silicone grease which should be applied to the distributor cap, sparking plug leads and terminals but in practice this remains effective only for a limited time. Much more effective protection can be obtained by spraying a preparation known as Holts Ignition Sealer (obtainable from Halfords and most garages and accessory dealers) over the cap, leads and ignition coil. As this dries it forms a flexible waterproof coating that will not flake or peel off and which resists oil and petrol. It will, of course, be necessary to renew the protection when any of the parts are dismantled.
An alternative scheme is to fix a sheet-metal baffle behind the grille in such a way that, while it does not unduly obstruct the flow of air, it will deflect rain and spray away from the ignition components. On later cars a baffle of this type is fitted as standard and for good measure the distri¬butor is protected by a moulded rubber cover which can, of course, be fitted on earlier cars. Combined with a spray of Sealer on the ignition leads and sparking plug terminal caps, this should be the complete answer to condensation and water-spray problems.