Why did windshield wipers stop working on a jaguar s type?

Answer 1

I have a X-reg. (2001) Jaguar S-Type and the windscreen wipers stopped working after 99,000 miles. After the fault developed they would give one sweep then freeze at a random point. With the power on they could be forced to a different position, but were very stiff. The cost for a garage to replace the wiper motor and linkage was in excess of £500, so it looked terminal. The service manual describes an involved process with brake servos having to be removed to get access. Even doing it yourself a replacement motor and linkage would cost over £200. The car could be saved if I could repair, in-situ, the existing mechanism: this I have successfully done.

My wiper mechanism failed because the driver's side shaft, to which the wiper-arm is connected, had corroded in the bearing and seized. This is caused by gallons of rain water passing over it due to the design of the car. My wiper motor had not been damaged by either the fault, or my attempts to push the wipers across the screen, so I was lucky!

To repair the fault. Mark the position of the parked wipers on the windscreen using masking tape and a felt-tip pen. Lift up the bonnet and remove the two plastic stoppers at the ends of the wiper arms. Remove the nuts thus revealed and wiggle the wiper arms off the splines. The manual says there is a special tool for this, but I fortunately didn't need one. Mark up which wiper arm goes on which shaft, so that any differences in the splines and blade wear will not be swapped about when you replace them. Remove the plastic panel that crosses the car at the rear of the engine compartment. The front of this is fastened with plastic plugs. To get these out press the centre in about 4mm (take care not to push it straight through or you might lose it) and lift out the plug. To reassemble reposition the centre part so it protrudes a few mm from the body of the plug then, after inserting the plug through the plastic panel and the car chassis, press the centre down until it is flush. Remove the screws from the rear of the plastic panel. These are aluminium and have star drives; they will easily damage if you use the wrong type of screwdriver. Be careful not to lose the black plastic stand-off washers that are beneath these on the underside of the panel. The panel should now lift out over the wiper shafts. Take care not to damage the plastic water-guide that fastened to this panel is about two-thirds across at the front. Also be careful not to remove the rubber seal from the bottom of the windscreen. It is easily re-fitted, but is a job less to do if it stays in place.

You can now see the wiper shafts and the linkage mechanism on the driver's side of the car. The motor is on the right underside of the assembly as you look from the front. I did not need to remove the motor and therefore can't suggest how to do it. The wiper shafts have each got a plastic shroud over them, presumably to stop water ingress. Carefully remove these and note which goes where. On my car the driver's side shaft was solidly rusted into the bearing. I applied "Plus-Gas" and left it overnight.

The following day I released the linkage from the motor by undoing the single screw from the centre of the crank. To get a spanner in required the wipers to be away from the parked position. This may be difficult to achieve if yours is totally stuck, but should be possible. If you try and force the mechanism have power to the motor, as it will be locked against the worm gear otherwise and keep your fingers well clear of the linkage. Note: when re-fitting the crank to the motor shaft it only goes on one way (one end is slightly curved) - this is to ensure the auto park is at the correct position. With the linkage free I used the wiper arm (refitted tightly to the splines) as a lever and began to gently work the bearing(s). It was slow progress but over time with many applications of Plus-Gas it freed up. I carefully removed the circlip (it would be a good idea to have a spare in case this breaks!) and washer from the wiper shafts to enable better access to the bearings, which are sintered bronze. I then flushed out as much rusty debris as possible with Plus-Gas and the airline, before injecting lubricating oil into the gap. It was possible, with the circlip removed, to work the shafts up and down in the bearings to force the oil into the space between the two. Finally I replaced the, cleaned, washer and circlip and put a large dollop of grease onto the top of the bearing and around the shaft before replacing the plastic shrouds.

Refitting is the reverse of the above noting the observations I have already made about positioning the crank, wiper arms etc.