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Helpful Mini Hints

Hints On Bleeding Brakes:
Most workshop manuals have a basic description of bleeding the brakes on your mini. Use these suggestions if you are having problems with bleeding your brakes.

Getting no fluid out of a bleed nipple Look at the simple things first, is the master cylinder topped up with fluid? It is surprisingly easy to forget to do this! If you have fluid in the master cylinder, try removing the bleed nipple entirely and see if you get flow under pedal pressure.

· Case 1. Fluid squirts from line: You have a blocked or corroded bleed nipple, which will need to be cleaned out with an awl or similar pointy tool, or replaced.

· Case 2. Still no fluid: Unscrew the hose at the car side so it doesn't twist or kink, and see if you get a stream of fluid under pedal pressure. When testing, have a wadded rag over the end of line to catch the fluid - the pressure is great enough to spray the other side of the garage, get in your eye or on your paint, etc. Also, press on the pedal about a dozen times when doing this; if the fluid all drained out of the system before you started bleeding the brakes, (if you overhauled some part of the brake system) it can take a surprisingly long time to pump fluid throughout the system.

Soft brakes even after bleeding.
You probably still have air in the system somewhere. If you have had parts of the brake system disconnected, ensure that the bleed nipples for the wheel cylinders and front callipers are at the top, so that the air can all escape during the bleeding process. (The air bubbles rise to the top.)

Front brakes bled, but no luck at the other end.
The pressure limiting valve may be operating, try to press slowly on the brake pedal so that the fluid goes through with out making the valve close of, or the pressure limiting valve is seized this also means that the back brakes don't work either. If so the valve will have to be repaired.

You have tried all of the above, but still have no luck! You may want to invest in a simple vacuum pump to bleed the brakes. One such tool, is the "Mityvac Vacuum Pump / Brake Bleeding Kit." The pump is applied to a bleed nipple, and pulls fluid through the system. This technique has the advantage that the master cylinder does not require "priming" in order to get the bleeding process started. In my experience, the vacuum pump does a good job and is a one-person operation (with the exception of checking the results in the "conventional" fashion).

If you haven't fixed your brakes what's stopping you?

Changing the speedometer cable:
1. Ensure that the engine is cool.
2. Follow the cable down from the back of the instrument cluster to the top of the gear box.
3. Alternatively, remove the right-hand road wheel and try to reach the end of the cable from below the gearbox.
4. Undo the knurled nut which should be hand-tight.
5. If access is tight, remove the radiator.
6. If the nut is too tight, wear leather gloves for better grip.
7. If the nut is still too tight, use a 7/16 socket to undo the speedometer gear assembly which can then be removed from the gearbox.
8. To prevent future problems, clean the speedometer cable nut threads and the fitting threads, lubricate with antisieze grease and tighten to hand-tight.
Ensure there are no sharp bends or kinks in the new cable. Cables vary in length depending on the year of car and whether it is RHD or LHD - specify when ordering a new cable, or measure your present cable and order one the same length.

Chrome side trim installation:
New "plastichrome" side trim is purchased in rolls.

1. Purchase only good quality replacement trim, which is easier to install.

2. Heat the trim with a heater, dryer or hot water until it becomes slightly pliable - do not overheat or the trim will lose its elasticity and be more prone to detach from the body.

3. Ensure the trim is installed so that the natural curve of the trim (the way it was rolled up) follows the sharp bends on the inside of the front/rear wheel arches, not following the contours of the wheelarches themselves.

4. Depending on the year of your car, the trim is held on by self tapping screws or pop rivets. Replace these with new stainless steel items to prevent rust.

5. Work slowly and patiently.

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.

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.

Has your Mini odometer failed to turn over at the thousand point yet the speedometer is still OK? If so, then don't despair - clearly the cable has not broken and the following tip may be of use.

Firstly remove the speedometer assembly from the binnacle noting the position of wires and globes. Take it inside to the clean kitchen table and good light. Carefully spring off the chromed escutcheon and glass and clean both. Undo the two screws holding the mechanicals to the case and gently lift out the mechanism taking care not to bend or dislodge the indicator needle from its shaft. You will now note that the pawl that operates the odometer has probably lost its chamfered edge. Early model pawls were brass while later ones were nylon. Slide off the spring clip and remove the pawl. While you are carefully filing the correct chamfer onto the pawl, ask yourself why it should have failed. It appears that in most cases the lubrication in the odometer has thickened and increased the torque needed to turn over the numeral drums, thus placing too much load and stress on the pawl.

Two options are open, either lubricate the shaft and interconnecting gears SPARINGLY with light oil (kerosene) or if you have the patience, dismantle the drums and gears from the shaft. Before final assembly, clean the numerals on the drums with a SOFT toothbrush and warm soapy water, dry carefully and you will be pleasantly surprised with the bright display.

Finally, if you ever have to change the complete speedo assembly note the number above the odometer eg. 1280 - this refers to the number of turns per mile for which it is calibrated. The turns per mile depend on the rolling radius of the tyre and of course, the differential ratio. Those of you having a variable speed motor can calibrate the speedometer against the odometer by turning the input shaft anti-clockwise at the correct speed. Use a piece of 3/16 inch (5 mm) rod filed down to a square end as the speedo drive. For a 1280 turns per mile unit, 1280 turns per minute equals one mile per minute equals 60 mph. With the whole unit in the correct orientation, you can then move the pointer on its shaft to indicate the correct speed. Be sure to make it a little optimistic to avoid speeding fines! Those of you with a variable speed electric drill with reverse have the ideal tool to perform the calibration. Drills without reverse will need an elastic band as a belt drive to obtain the reverse direction. By varying the ratio of diameters on the drill drive and that into the speedo you can check the calibration at other speeds.

Petrol Tank Drainer:
Do you have difficulty in operating the petrol tank drain tap? In fact when was the last time that you drained all the rubbish from your Mini's tank? Spare your petrol pump and carburettors constipation. If you have a Mini with the drainer's 50 mm of tube still intact then, rather than struggle with a small open ended spanner in the confined space (or break off the tube like some rough mechanics) make up a new tool using a length of 1/2" OD square section steel tube. A length of about 200 mm makes an ideal extension shaft which slides over the drain tube and fits into your 1/2" drive socket. The other end will probably fit into a 9/16" socket or ring spanner. Incidentally, ensure that your socket has a hole through which to pass the tube!

Get a metre or so of this square tube as it is also a boon in the removal of the inner drive couplings. It allows you to access the nuts from outside by passing the extension shaft through the drive shaft slots in the subframe to operate a ratchet drive spanner.

When changing the inner speedometer cable place a zip tie around the outside of the outer cable behind the carburettor. This prevents the ferrule sliding down behind the engine. Tighten the lower ferrule finger tight only. Trying to remove a cable tightened with vice grips or similar with the engine in the car verges on the impossible.

Braze or weld about 6 inches of wire to the head of the four bolts that hold the mounts to the subframe. The bolts can now be guided into the appropriate holes and held by the wire while the washers and nuts are attached. Leave the wire on if you want for undoing next time. Note: Always put the bolt in from the inside of the subframe.

Always ensure that the hose clamp is put on so that the screw driver slot is as close to the rear of the radiator cowling as possible. If this isn't done, the hose clamp can not be undone with the engine in the car. ( This is often done when the engine and radiator unit is fully assembled before putting into the car). A suggestion when putting a hose on in the car is to bend a piece of stiff welding wire so that one end has a small loop in it. The loop then holds the hose clamp in position while the screw is tightened. The wire loop is held under the clamp with the left hand while the screw is tightened with a long screw driver held in the right hand.

This is especially for alloy parts such as thermostat housing and water pumps. Scrape or wire brush away all signs of corrosion then wipe the area which goes under the hose with 'Moly grease' before replacing the hose. This helps prevent corrosion. The same can be done to the face of alloy components where they bolt down onto a gasket.

Always use the genuine type fixing screws with the hexagonal head. Longer screws will puncture the radiator core and slotted or phillip type screw heads can not be undone with the unit in the car. There is insufficient clearance for a screw driver at the back of the radiator. Take special note of this hint when assembling the unit outside the car!

This applies especially on cars subject to 'aggressive' use and with standard manifold and exhaust pipe. (Not Cooper type). Remove the engine pipe and cut 3 - 4 inches from the pipe between the top collar and the first mounting point on the gearbox. Replace with a section of flexible exhaust tubing and securely clamp at both ends. This allows some degree of flexing and minimises broken collars on the end of the engine pipe.

This can often be caused by the indicator cancelling T piece on the steering column shorting out on the live section of the switch mechanism. Check and adjust for clearance.