The tailgate must be removed to carry out the restoration of the electrical conductors of the demister grid. Exercise due care in this operation as the frame is relatively flexible and the glass is easily cracked. Protect all the surrounding car bodywork with soft blankets before detaching the tailgate hinge nuts and actuator piston securing bolts. If possible work with an assistant and be prepared for the considerable force exerted by the actuator pistons.
Place the tailgate upside down on a rigid table surface protected with soft blankets and work with good lighting and magnifying spectacles. The conductive varnish contains 4-Methyl-2-Pentanon and I strongly recommend that it be applied out-of-doors or at least in a very well ventilated area. Prolonged inhalation of the vapour must be avoided.
With impregnated metal polish pads clean the sound conductors adjacent to the defective areas to a bright surface and then remove all traces of the product. Apply masking tape on either side of the lengths to be repaired and apply the conductive varnish in several coats at intervals of about 5 minutes. Shake the phial frequently to maintain a uniform particle distribution. After about 5 coats have been applied in each area, wait 30 minutes and then gently peel away the masking tape. Repeat this entire operation two or three times at intervals of 24 hours until a satisfactory conductor thickness has been built up.
Each of the conductors of the demister should have a resistance of about 10 ohms, so that the entire grid has a resistance of about 1 ohm and will draw over 10 A. Do not apply electrical power to the grid for several days to allow the conductive varnish to dry fully and the resistance to fall to its final value.
When replacing the tailgate check the angle of the frame connecting brackets relative to the actuator pistons and file or mill the frame mounting faces of the brackets to adjust the angle for precise alignment. This will ensure that the ends of the pistons do not scrape against the fixed frame when the tailgate is being closed.
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