Defender’s wiper blades not giving you a clean sweep? Martin Domoney of Land Rover Owners magazine explains how you can fix them...
- Tools & Kit: Socket and spanner sets, 8mm ratchet spanner, Screwdrivers, Trim tools, Side cutters, Fine file, LM Grease, Threadlock, Pliers
- How Long? Three hours
- How Difficult? 2/5 - Easy
- Product(s): Defender Wiper Drive Cable 1987-2002, Defender Wiper Drive Assembly (OEM)
- Safety Advice: Disconnect the battery before starting work. Wear eye protection when cutting the cable.
Many of the quirks we appreciate (and sometimes endure) on our beloved Land Rovers would be arguably unacceptable on any other vehicle. The operation of the windscreen wipers is a case in point.
Because a Defender’s windscreen is quite short, it doesn’t allow fitment of very long wiper blades. Due to their diminutive size, it’s vital that the blades travel through their full intended stroke to clear the screen properly of rain and debris. Thanks to the Defender’s unusual cable and gear operated wiper system, this is quite often the opposite of what happens.
Martin’s taking on the 90’s wiper system today. ‘The later TDCi dashboards are all in one piece, which can make this job a bit trickier,’ he says, blissfully unaware of the wiring nightmare that lurks in the LRO Defender’s dash.
Over time, the ridges on the wiper cable that locate on the drive gears wear out, causing slack in the system. The same thing happens with the gear teeth themselves, and a small amount of play here is amplified at the end of the wiper arm where the blade connects. This problem is made worse when the system runs dry; a common issue, as the old grease dries out and no longer provides lubrication to the gears and cable.
So if your Defender (or the similarly-equipped late Series IIA & III) wipers do an even poorer job of keeping the screen clean than usual, it’s entirely possible your wiper cable and wheelboxes need replacing.
Luckily, after a bit of a stripdown, it’s an easy job to carry out.
…is the main symptom of worn wheelboxes and an old wiper cable. The wiper arms fail to return to the horizontal position when the motor stops. When switched on, they won’t sweep through their proper travel, reducing visibility – not good.
Start the stripdown
To access the wheelboxes, the dashboard top
panel must be removed. Start by popping out the
Land Rover emblem from the passenger-side grab
handle and removing the screw beneath. Then undo the vertical screws and wiggle the handle free.
Unscrew the heater controls
Head to the driver’s side and undo the various
screws securing the heater control panel to the
end of the dash. There’s no need to disconnect the
cables; once unscrewed, the heater controls will allow
enough movement for the top panel to come past.
Undo the top screws
Unscrew the windscreen vent plastics from the
dash top. Undo the two screws in each, then lift
the vents out. The three larger screws holding the dash
top down can be removed now – take care not to round
the heads out, because they can be surprisingly tight.
Position the binnacle
The last thing stopping the dash top panel being
removed is the instrument binnacle. Undo the
screws securing it to the dash and ease it forwards a
few inches, allowing it to sit on the steering column.
Make sure the speedo cable and wiring aren’t stressed.
Remove the top panel
The top part of the dashboard can now be
wiggled forward and lifted away. The front of the
panel lips over a metal ridge on the dashboard’s frame,
so don’t try and lift it straight upwards or it could be
damaged. Once removed, store it somewhere safe.
Slide out heater duct
To access the offside wiper wheelbox, the screen
demister vent must be removed. It’s held by two
fiddly 8mm-headed screws; a ratchet spanner is a huge
help here. Once released, slide the duct up and out of
the dash, making sure the flexible tubing stays in place.
Access the motor
Next up, the dashboard corner piece concealing
the wiper motor can be unscrewed from the
bulkhead and removed. Ours is mostly rust at this point,
and is long overdue replacement. Undo the last screw
and slide the plastic dash trim strip away.
Off with the arms
The windscreen wiper arms can be removed from
the splined adaptors. This allows the spindles to
turn freely as the cable is pulled out. Use a screwdriver
to depress the tab, then slide the arms off. They can be
stubborn, so persevere and don’t force them.
Release the spindles
Now remove the adaptors from the spindles. Ours were held by 8mm screws, but they’re more commonly attached with grubscrews. With the adaptors off, use an open-ended spanner to undo the clamping nut and remove the fibre washer from each one.
Unbolt the motor
Depress the locking tab on the electrical plug, and slide it out, then remove the lower wiper motor mount screw. Loosen the top screw but don’t remove it, or the captive nut plate will fall off. Slide the motor clear of the bracket, collecting the rubber pad from behind.
Disconnect the cable
Turn the motor around so the removable plate is easily accessible, then undo the small screws holding the cover on and lift it away. Use a small screwdriver to release the e-clip from the motor gear, taking care not to lose the washers.
Slide the cable out
Lift the end of the cable off the gear pin, then slowly pull the cable all the way out. Make sure the motor isn’t allowed to hang on the metal tube; it may bend and cause the cable to bind when refitted. When the old cable is out, don’t bin it just yet.
Undo the wheelbox nuts
Peer down the gap where the dash top panel was; you’ll see the wheelboxes’ bodies. There are steel tubes between the motor and each wheelbox where the cable runs, so note how they fit before undoing the 8mm nuts with a shallow socket or ratchet spanner.
Retrieve the pieces
Wiggle the end cap off the offside box and remove the tube between the two. Lift the backplates out of the dash, then slide the main part of the wheelbox back so the spindle clears the bulkhead. The boxes can be a bit fiddly to wrangle out of the dash, so be patient.
Old and new
At first glance, the teeth on the original wiper wheelbox’s gear don’t look too badly worn. But even slight play between the gear and drive cable here translates to a lot at the wiper arm. This is why it’s vital to lubricate the new gear and cable before rebuilding.
Wiggle the new wheelboxes into place, and push
the spindle all the way through the hole in the
bulkhead. Slide the fibre washers on to the spindles
from outside and spin the nuts on to hold the
wheelboxes in place, but don’t tighten them up yet.
Align the tubes
With both wheelboxes positioned, slot the long connecting tube, motor tube and end cap into place. They should all sit nicely in place, with the flared ends of the pipes fitting snugly between the wheelbox body and the backplate.
Nip up the nuts
When you’re happy that everything fits nicely, fit the new 8mm nuts to the studs, and nip them up to sandwich the two pieces together and secure the tubes. When the 8mms are snug, tighten up the two spindle nuts from outside the vehicle.
Trim to length
The oversized new cable must be trimmed to the correct length. Lie the new cable next to the original to identify where it needs to be cut, then use side cutters to trim away the excess. Use a fine file to de-burr the cut end so the cable slides home easily.
Apply grease sparingly along the length of the new wiper cable. This will ensure it slides well in the tubes, and will reduce wear on the wiper wheelbox gears. It doesn’t need to be packed with grease, just coated; too much could put extra load on the motor.
Now fit the new cable
Slide it into the metal tube and push it right in. Arrange the shims as they were before removal, then use long-nose pliers to snap the e-clip back on to the motor gear’s post, securing the cable end. Refit the cover plate and motor, tighten the screws and plug it in.
Check it all works
Now’s a good time to flick the ignition on and check everything’s moving as it should. Select each speed on the stalk; make sure the wiper spindles start and stop turning at the same time, and check there are no untoward noises from any components.
Build up the spindles
Slide the supplied rubber boots over the spindles to protect the threads. Remove the grubscrews from the adaptors and apply a drop of Loctite to their threads; these often back off, resulting in the wiper arm falling off! Align the arms and clip them into place.
Refit the dashboard
It’s time to screw back all the bits of dashboard you removed. Take extra care when refitting the driver’s-side screen duct, and make sure the flexible pipe is connected properly at both ends. Continue rebuilding until you run out of parts and screws.
Passing the screen test
Look at that! The wiper blades now park perfectly parallel to the bottom edge of the windscreen, and the swept area is noticeably larger than before. This is one of those jobs that’s probably put off for a long while – but once it’s done you’ll wish you’d done it ages ago. For a few hours’ work and about 70 quid, the wipers are as good as new. Result!
This article originally appeared in Land Rover Owners Magazine and has been reproduced with permission. Article is written by Land Rover expert Martin Domoney.
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