911 Wiper Mechanism Change
Richard Stephens 7^th December 2023
911SC Technical Advisor

When driving the SC the wipers were moving around up the windscreen. There was lots of play in the whole wiper mechanism. Investigation was needed. Removal of the mechanism is a bit fiddly but very do-able by the home mechanic.
The process for removing the wiper mechanism consists of the following steps:
I put some masking tape around the wiper mounts to stop the wiper mechanism threads chipping the paint.



Remove the wiper caps and then the blades, remove both big 22mm nuts, remove 4 screws on the air intake vent gauze, remove 2 long bolts from heating box. From inside the car push or pull out the temperature gauge and oil pressure gauge.
This will give you more access to some fiddly bolts. Then move to parts under the bonnet - pull carpet off the backboard, remove backboard (4 bolts), remove stay, undo 3 jubilee clips on the heating pipes, disconnect the heating box drain pipe. Note the control wires for the heater box do not need to be removed. The heater box can just be pushed out of the way.
You should be able to tackle the wiper motor 3 bolts now from inside the car through the gauge holes. First there is a nut to be removed from the middle of the wiper motor. Then remove the 3 bolts. Note the wire positions and colours on the wiper motor. It should be free now. Once removed then the wiper mechanism can be removed. The fresh air plastic box may need to be removed if it gets in the way. The complete wiper mechanism below.



Below is the nearside wiper mechanism which is rusted solid. It can be stripped down and refurbished. New mechanisms can be obtained but at a cost of around £400. Note that pre-73 mechanisms have a different bolt hole configuration. You can drill new holes but it’s best to get an SC version.



You can see the brown rust stains where the water has been getting into the wiper mechanism causing it to seize up.



Installation is the reversal of the removal. Before you put everything back check the operation of the wiper seeing that it is setup in the correct position and parks correctly. The position the mechanism connects to the wiper motor may need to be altered. Just remove the nut and pop the metal piece off and re-position it. Be careful to put the wiper blades on when you know they are in the correct position. They can scrape the paintwork if mounted in the wrong positions.
Below the SC ready to go when the warmer weather comes.