The Mini Mag

Volume 1 Number 5 July 1999.

HELPFUL HINTS


MINI TIPS - Windscreen Wipers
Have your windscreen wipers got the "flip flops" and refuse to park neatly? If so, then perhaps the following tip may help. First check that the wiper motor is securely mounted and that the rubber bushes fitted into the bulk head have not perished. Also check that the drive take-off for each arm is tight on the casing of the sliding flexible drive. If the sweep of the arms is still too great and the blades foul the windscreen rubber then the fault will probably be in the gearbox of the motor. In some cases this can be repaired on the DR3A motor.

Firstly, mark the relative position of the gearbox cap to the gearbox body as this sets the cancel position on the self cancelling unit. Remove the screws holding the cap to expose the nylon drive gear. Some of the teeth on this gear will wear more than others and the trick is to remove the steel drive flange from the gear and rotate it around (by gently moving the wiper arms) then remount it on the nylon gear thus presenting the unworn teeth to the worn drive at the high torque position. If it is apparent that the gear has been rotated before, then get another wiper unit.

Check also the end float of the motor shaft. If this is, say, more than 0.010 inch (0.25 mm) then a careful selection of a new thrust washer should be made. If the armature is removed from the motor body then the commutator and brushes should be checked.

If the existing grease in the gearbox is dry and hard then it should be replaced. It is also most desirable that the flexible drive and each of the wiper take-offs be removed and greased. The large nuts on each of the wiper arm drives should be given a little squirt of RP7 or similar and allowed to penetrate before unscrewing. When replacing the angled spacers (early models) back onto the body ensure that all seals are in good order to avoid water leaks.

MINI TIPS - Battery Box
Have you noticed that the battery seems to be sitting a little lower in the boot these days? If so, then get on your hands and knees and look under the back of your Mini and you will find that the battery may well be falling out through the corroded bottom of the box. Repair the box by either using a replacement metal assembly or by separate fabrication. Fibreglass would appear to minimise the chances of corrosion in the future but if you are to continue with steel then ask yourself why it should corrode. The answer is simple - acidic fumes from the charging process are trapped in the battery box by the fibre cover (if it is still complete) and this is compounded by the overall sealing of the boot floor mat.

The task is to minimise the fumes. Overcharging is the major cause of the fumes and it could be that the generator and regulator could be in need of attention. Some fumes are inevitable and to reduce their presence use a piece of 8 mm (5/16") nylon or PVC tube as a breather. Depending on the length of the battery it may be possible to push the battery hard forward and drill a hole in the rear rubber plug and push the tube through so that it projects about 5 mm below. If it is not possible to use the existing rubber plug then drill a new hole in the right rear of the box. Either make the hole large enough to fit a grommet or used a a little bead of silicone sealant on the tube. The overall length of the tube should be sufficient to project above the top of the battery case by about 10 mm.

Now as you drive along the fumes are drawn out by the slip-stream under the car.