The problem?
Windscreen wipers not working on my MGF, despite having checked the fuse and the linkages, so it is the motor which needs replacing. The wiper motor + linkages are often sold as a complete unit so a quick check on ebay and a used windscreen wiper motor and linkages is found just 10 mins from me.
Not raining so I set off. Half way there it starts to rain lightly, so at each junction a quick wipe clears the view.
Tools needed:
10 & 13mm sockets, 32mm socket or large adjustable wrench/spanner, Cross head screwdriver
The Fix
1) Open the bonnet and remove the front bulkhead cover.
This is held in position by x4 10mm nuts ( A ), two on the LHS, two at the bottom of the cover in the spare wheel well and one retaining piece with a crosshead screw ( B ) to the RHS of the cover above the brake master cylinder/servo. Ensure the cover is free from the four fixed bolts and then lift the cover away.
2) Remove the wiper arms, then the 32mm nut and washers from each arm.
Before removing the 13mm bolt, you need to move the wiper linkages such that the wipers would be in the upright position. You need to do this to be able to get the motor and linkage mechanism in and out of the car.
Positioning the linkage arms can do in one of three ways.
a) If you still have some movement use the the wiper switch then switch off the ignition half way through the sweep.
b) Open the ball and socket joints on the linkage arms or
c) open the motor casing, a pair of small torx head screws, then rotate the motor by hand.
Having done this remove the 13mm bolt.
3) Next you need to remove the scuttle panel. Watch out for the screw covers, they are the work of the devil and will fly away to some hidden location if you do not put your hand over them. You have been warned.
The hooks referred to are shown in this photo, they slide under the glass of the windscreen to hold the ends in position
4) Remove the connector leading to the motor. Slide the motor and linkage mechanism out of the car. It is tight but gently lifting the motor up will help.
5) You are now ready to replace the mechanism and refit is just reversal of the above. To make sure the wipers end up in the correct position operate the wiper motor and allow it to 'park' before refitting the wiper arms.
What was the problem?
Wanting to know why my wiper motor had failed I took it apart to discover it had water in it! Never a good sign in an electric motor
In comparison with the replacement motor
The problem is that oxidisation of the metal casing of the motor distorts the rubber gasket seal allowing water in.
On the new motor I cleaned up both parts reassembled it, then smeared some grease around the join.
It may be worthwhile checking your wiper motor. After following 1) above you can get access to the motor and check it's condition. A little research has revealed this is a known issue and some people have gone as far as drilling a drain hole in the underside of the motor. I would not recommend this, I believe you are far better stopping the water getting in in the first place.