The wiper bearings on our 2005 Renault Scenic failed last week, which is apparently another "common fault" for that model. The official fix is to replace the entire wiper arm assembly, at a cost of around £100, however there are also repair kits available for around the £10 mark.
These kits basically consist of a pair of skateboard wheel bearings (conveniently they are exactly the same size), a pair of nut / bolt / washer bundles and a drill bit. Mine came with instructions, but to be honest they didn't make a lot of sense to me.
I eventually managed to piece the process together by combining information from the included instructions, a workshop manual and several forum posts made by others in the past. It's not a particularly difficult job once you know what you're doing, so I've written up the process here in the hope that it helps someone else.
Task 1 - Set the wipers to the correct position
Before we do anything it's key to ensure that the wipers are in their resting position. If the bearings have failed it's likely that the wiper arm will have jammed and landed in an awkward way. To do this, just manually move the failed joint back into approximately the right placeand flick the wipers on for one cycle. The joint will pop back open but when pushed back the wiper should be in its normal neutral position.
Task 2 - Remove the wiper arm assembly
Nobody wants to work reaching across the full depth of a car bonnet and this job requires some brute force so your first job will be to remove the wiper arm assembly. The workshop manual says that you should remove a load of trim beforehand, however I found there was plenty of room with the bonnet shut.
The wiper arm assembly is a hinged F shape, with two axles at the base which look like this:
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| Wiper axle (with ball bearings and swarf from failed bearing) |
You will also need to remove the arm cover. This is achieved by inserting a screwdriver into the slots at each end and gently levering the catches out from behind the metal, however you may find that easier once the assembly is off the car.
Now that the nut is exposed, undo it. Be sure to hold the wiper arm in place while you turn so that you are levering against that rather than the wiper motor / linkage.
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| Wiper axle with nut cover removed |
Now that the nut is exposed, undo it. Be sure to hold the wiper arm in place while you turn so that you are levering against that rather than the wiper motor / linkage.
Repeat this on both arms, making sure to mark the relative position of the arm to the axle. This is key as you need to ensure that the wiper arm is positioned correctly when it is replaced.
The arm assembly pulls off the spline fittings without too much force, however it may need a bit of a jiggle.
Task 3 - Removing the outer chase
When these bearings fail they invariably break at the join, so you end up with a gutter full of ball bearings, the outer chase still attached to one part of the assembly and the inner chase still attached to another. The outer chase will be left in the actual wiper arm part of the assembly, it is a tight press fit and will likely be pretty well corroded into place. In fact, it's difficult to even tell that it's a separate part.
It's advisable to spray a load of WD-40 or similar on at this point to aid in freeing things up as the next part can be rough.
The outer chase needs to be removed by hitting it out. There is a retaining lip on the back of the arm (i.e. the window side) and so the chase needs to be withdrawn from the front. I found a 14mm socket with a short extension was perfect for this job as it was small enough to fit inside the retaining lip but large enough that it pressed firmly on the chase.
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| A 14mm socket is ideal to apply pressure on the outer chase |
Support the arm assembly as best you can (i.e. rest it on the edge of a wooden bench as close to the area being worked as possible) while striking the socket firmly. It took me around 10 minutes of vigorous smashing with a lump hammer to get the chase out, but eventually it went:
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| The outer chase, finally freed from the wiper arm assembly |
Make sure to give the newly-vacated arm a good clean and file off any burrs as the replacement bearing will need to be installed back into the same location.
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| Cleaned up wiper arm assembly showing rear lip |
Task 4 - Fit new bearing to wiper arm assembly
Once the wiper arm assembly is smooth and clean, the replacement bearing will need to be press-fit into place. Unless you're He-Man, this is best done using a vice. |
| Pressing the new bearing into place with a vice |
Push the bearing into place by hand as far as it will go (i.e. hardly at all), then put the arm & bearing into a vice, padded out by a piece of wood or similar to avoid damage to the bearing. As the vice is tightened, the bearing should slide in smoothly, evenly and easily. If it does not, something is wrong - check the alignment and re-try.
The inner chase of the failed bearing will be attached to the short part of the wiper assembly - again it will be difficult to see that the chase is not just part of the arm, however as shown in the picture below there is a curved groove where the ball bearings used to run:
The the castellated top part of the upright holds the inner chase securely in place and therefore it needs to be ground off. This can be done using a Dremel-type tool, a metalwork grinder or, at a pinch, a hand file.
Again, to separate the chase from the arm you may need a lot of spray lubricant and brute force. Once the castellations are ground off you may find that the inner chase is still stuck solid. At this point I dremelled two sides of the chase flat so that I could grip it in a vice and apply a good twisting force to the arm. Once it was possible to rotate the chase it came off quite easily.
Once the chase is removed grind out any burrs on the pin and clean it up, ensuring that the top surface is level.
Once that is done, the wiper arm assembly should look quite good, as below:
At this point the inner chase of the new bearing should still move smoothly.
Task 5 - Remove the inner chase
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| Short arm with inner chase attached |
Again, to separate the chase from the arm you may need a lot of spray lubricant and brute force. Once the castellations are ground off you may find that the inner chase is still stuck solid. At this point I dremelled two sides of the chase flat so that I could grip it in a vice and apply a good twisting force to the arm. Once it was possible to rotate the chase it came off quite easily.
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| Inner chase removed by gripping it in a vice and jiggling the arm out |
Once the chase is removed grind out any burrs on the pin and clean it up, ensuring that the top surface is level.
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| De-burred and cleaned pin |
The pin should slide easily into the centre of the new bearing and the two parts should swivel cleanly.
Task 6 - Drill out the pin
Whereas the old bearing was crimped into place, the new one will be held in by a bolt and lock nut. Therefore the upright pin on the short arm needs to be drilled through.
This is a pig of a job. I snapped 4 drill bits in the process, so take your time and apply lubricant as necessary to get a straight, clean hole as centrally as possible right the way through. Start with a small pilot hole and expand if it helps. Better still, find a friend with a pillar drill.
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| Drill the pin out (be sure to get the drill central, not like in this shot!) |
Task 7 - Re-assemble and re-fit
At this point, the assembly should be put back together and held in place using the bolt, washer and lock nut provided in the kit. It's sensible to apply grease at this point to prevent the new bearing from rusting straight through.
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| Re-assembled wiper arm assembly (rear) |
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| Re-assembled wiper arm assembly (front) |
At this point, check that the mechanism moves freely. Adjust the tension as necessary to ensure free movement but without sloppiness / play in the joint.
Re-fit the wiper arm assembly to the car:
- Press-fit the wiper arms into place, ensuring that the marks made earlier line up correctly
- Tighten the nuts, ensuring to lever against the wiper arms rather than the motor / linkage
- Clip the arm covers and nut caps into place
At this point the job should be complete. Try out the wipers and make tweaks as necessary.
I only replaced one of the bearings on my wiper and found that it soon wore out again, really quite quickly. It was a fairly quick job to swap it again but the same thing happened to that. What I realised at that point was that although only one bearing had actually (catastrophically) failed, both were very worn. The better of the two bearings had excessive play which in turn put strain on the other and caused it to fail prematurely. The second time around I replaced both bearings together and it has lasted much longer - in fact, as of yet, neither seems to be failing.
In summary - the kits come with a pair of bearings for a reason. Be sure to replace both bearings at the same time.
NOTE - A lesson learned the hard way!
I only replaced one of the bearings on my wiper and found that it soon wore out again, really quite quickly. It was a fairly quick job to swap it again but the same thing happened to that. What I realised at that point was that although only one bearing had actually (catastrophically) failed, both were very worn. The better of the two bearings had excessive play which in turn put strain on the other and caused it to fail prematurely. The second time around I replaced both bearings together and it has lasted much longer - in fact, as of yet, neither seems to be failing.
In summary - the kits come with a pair of bearings for a reason. Be sure to replace both bearings at the same time.
