VW Golf MK4 Wiper Base/Mechanism Replacement

I had one of the wiper shafts shear off when tightening a wiper arm. (I used torque wrench to tighten to correct torque value but still..)

I had to go to a local parts shop to get a replacement 3rd party part quickly. Otherwise, it would be impossible to drive the vehicle if it rained. Since it was the drivers side arm's shaft.

In the end, I had to do the same procedure again to install original VW part because the 3rd party part was not a good fit after all. More about that later.

You may want to do this in a warm environment. At least 15+C temperature to not break the plastic parts.

Required Parts

Dow Corning / Molykote 111 Silicone compound for lubricating rubber/plastic parts.

WARNING: These are parts for LHD vehicles and some part numbers are different for RHD vehicles

1x 1J1 955 603 B - Wiper base for LHD vehicles
1x 701955754 - 14X9,5 grommet (attaches to wiper base)
1x 701955756 - Bush (attaches to wiper base)
1x 535 955 121 A - Crank arm (attaches to wiper motor)
2x 1J0 955 325 A - Operating linkage for LHD vehicles (attaches to wiper base and motor crank).
3x N 0143441 - M6X18 hex bolt with shoulder, self-locking (attaches wiper base to body)

If you want to change wiper motor bolts also:

3x N 90305302 - M6X10 hex collared bolt (attaches wiper base to motor). Apparently this item was superseded by N 90305304 but I had some problems with it. More about that later.

Required Tools

Wiper/bearing puller
10mm wrench
13mm wrench
Torx/Philips screwdriver (for pollen filter screws)
Patience

If you are replacing with original VW part, you need to buy wiper base and linkages separately. I recommend getting a wiper crank arm also.

In addition, probably a vacuum cleaner to clean up the space where the wiper mechanism sits. Mine was filled with leaves and soil! Now I know from where all the mud and leaves in my wheel arc was coming from! Yes a perfect compost!  Note to self: Install a net to the water deflector air holes to reduce leaf intake!

1- Remove Wiper Arms

First you need to remove wiper arms. I used a knife to pop up the protective plastic covers on top of the nuts. The nuts are 13mm.

Apparently VW suggests yanking the arms off by moving them left/right/up/down while pulling. You should not remove them this way!

I have loosened the nuts but did not remove them, then set a wiper arm puller in place to pull wipers out. It was not easy even with the wiper arm puller. The area is small so you will need a small enough arm puller. I used 2 different parts for this task.

The one on the left fits fine to remove wiper arms. However I used the one on the right to manipulate wiper base linkages. Some sites say you can use screwdriver etc. but it is a cumbersome process with screwdriver and you may damage connecting pieces with screwdriver.

2- Remove Pollen Filter Cover (1J1 819 537 C for LHD)

Remove the 4 screws which hold the pollen filter cover and remove the cover. This is very useful when removing the trim part which the pollen filter cover was connected to.

3- Remove The Water Deflector (1J1 819 415 B for LHD)

Unfortunately I did not take picture of this. However it is easy. I used a plastic trim removal tool to remove it. You will start removing it from the pollen filter side. I have put the trim removal tool between the deflector and windshield and also pushed it up using my hand from the hole of the pollen filter.

If you are applying pressures at the right place, you will feel that it pops out quite easily. So, try a few different locations. I found out the best place was near the corner of the windshield. Do not force it, you may break it if you force removal. Just take your time!

After removing it, clean both the windshield groove and also the water deflector extension which enters to the groove. Otherwise it won't fit well when you install it back. I used paper towels and just slided them several times to push all the dirt out. As you can see in the picture below.

4- Remove Wiper Base Mechanism

Once the water deflector is away, it is easy to see the wiper mechanism. I took the picture below after installing the new wiper, that is why it is so shiny.

The red arrows point to the 10mm bolts holding the mechanism and the green arrow points to the wiper motor connector.

You will first need to remove the 10mm bolts. Then wiggle the passenger side arm out and then use a flat head screwdriver to carefully remove the wiper motor electric connector before completely removing the base. It is tight, so you need to carefully wiggle it around. Make sure to not make big scratches on your paintwork.

5- Clean The Surrounding Area

I realized the surroundings were filled with soil (surely converted from leaves!) and leaves. You can see below the broken shaft also. This photo was taken when I removed the water deflector first time.

After cleaning what I could by hand, I had to resort to using a vacuum cleaner. The soil was wet so I would not recommend a normal household vacuum unless you change the bag right away after vacuuming.

Vacuuming clean the area pretty good. But I went one step further and washed the area and pushed remaining mud to the draining holes on the sides. While on it, I also removed the mud flaps and empty the collected mud from the wheel arc. Make no mistake, it gets filled with mud and cause rust if not cleaned regularly!

6a- Install Replacement Wiper Base/Mechanism

OK, you think the installation is reverse of removal so why do we need this section? You are correct that installation is pretty much reverse of removal. However I had some experience with a 3rd party part and I would like to relay it as a warning.

Because I was in hurry to fit something there before getting caught on rain. I went to local parts shop and bought a replacement.

Yes, the part is a topran 110 694 which says clearly that it replaces 1J1 955 603B (yes this is exact same part number that we needed). The good thing was that this part came with all the rubber bushings etc. But I think topran made a mistake because this item seem to replace 1U1 955 023 E which has drivers side linkage with part number 1U1 955 215 B and ength 66.5mm. But this is incorrect for Golf MK4. It seems to be for some Skoda models... hmm?

Aftermarket Part Problems

 

a) First of all, I could not properly adjust the driver's side arm to go until the correct position. It kept stopping ~6cm before the original went. I could not lift the resting position 6cm up because then the wiper was too high when resting. First I thought that I made a mistake but it seemed unlikely because wipers were resting exactly where they used to be originally.

I have then compared the linkage arms with the original part to see why this was happening. The arms on the base frame are different length for driver's side and passenger side. you can see this when you operate the wipers. The driver's side goes about 90degrees and passenger side goes ~110 (because it ends in front of the driver as you can see when it is working)

When I checked the original VW wiper part. I realized VW was smart enough to write the linkage lengths.

The passenger side 1J1 955 216 A and 62.3mm. Driver's side 1J1 955 215 A and 64.8mm. Wiper arm travels less when linkage is longer. So if you ever open your wiper frame and oil it, you need to make sure to put them to correct sides.

Now, the 3rd party part got the correct passenger side measurement but the driver's side showed 66.5mm.

So, if you think that driver's side does about 90degree turn with 64.8mm and 110degree turn with 62.3mm It means you get 20degree diffeence using 2.5mm meaning each mm is about 8degree for our purposes. So going from 64.8 to 66.5 is 1.7mm difference. It should reduce range about 13.6 degrees. This is unacceptable that I had ~6cm less wiped from the drivers side.

b) The material was too soft. Somehow the VW material is much harder. Even though I used torque wrench to tighten the motor bolts. I realized one bolt was just compressing the metal holder!

The issue is perhaps also because the 3rd party manufacturer wanted to make a somewhat square slot for this specific bolt. I guess they wanted to leave a higher error tolerance because you can adjust the motor using this space a little bit.

c) The original gromments between wiper base and car body are tough EPDM rubber pieces. With 3rd part wiper the gromments were very soft like jello and I could compress them to few mm using my fingers! I imagine it won't give much stability to the wipers and probably useless when they are so soft.

d) The original metal bushes which go inside grommets are shorter. The shorter length bush and harder grommet make the original VW part more stable and less wobbly. In the picture below, the original part is on the left. Topran part is on the right.

Although the topran grommet is also slightly taller, it is much softer so it does not achieve same characteristics as the VW grommet.

6b- Install Geniune VW Replacement Wiper Base/Mechanism

The genuine VW wiper base mechanism (1J1 955 603 B) comes with only 2 gromments and no bushes. So you will need to order 1 more grommet (701955754) and 3 bushes (701955756). While doing that, I also ordered 3 new bolts with collar (N 0143441) to attach wipers to body. The original bolts had washers and new version apparently has a collar. I ordered a crank arm (535 955 121 A) just to make sure that I have everything in case if I need and assumed the crank arm ball could be worn slightly over the years.

I also ordered 3 bolts to replace motor mount bolts N 90305302. This was apparently superseded and replaced with N 90305304 which is a hex collared bolt. However I hit a wall there because apparently VW also changed the design slightly. The crank arm was slightly lower and the bolts with collars were slightly taller and in combination it would not fit properly.

As you can see, original arm (on the left) has a larger gap for screws and also the ball joints are higher.  The arm itself is also thinner.

Here I press the end base flat on the table so you can see how they sit in their final position. The original arm (on the left) sits slightly higher.

Here you can see that the combination of new arm and new screw does not work well. Here it actually fits barely but scratches the screw and arm.

I had two choices, use old arm or old bolts. I liked the crank arm being little lower, because the ball joints were connected in a slightly awkward angle in the original arm and this makes it better. So I decided to use the older motor mount bolt/washer combination which gave a good clearance to the arm. This combination is not as high as the collared bolt.

Assembling Linkages to Crank Arm

Used a generous amount of molykote 111 silicone compound on rubber bushings. I installed the linkages to the arm first. Because once the arm is on the motor, it is difficult to fit the bearing puller to pull the linkages in. I have carefully pulled in both of the arms to the ball joints of the crank arm.

Assembling The Crank Arm

Important: Before removing the original crank arm, you must mark the position exactly. or you will have troubles setting it up later. I did it double to be sure 100%. First I have rotated the arm to a position which could be replicated easily with new arm. Second, I have painted an arrow parallel to the crank arm on the drive shaft.

You will need the bearing puller to remove the arm without rotating the shaft. I was very careful to not to change the position I set. After that, it is a matter of putting the new crank arm on the shaft and carefully tightening the nut to 20Nm.

Assembling The Motor To Wiper Base

Since the linkages are already attached, you need to move them first through the hole on the wiper frame and then tighten bolts of the motor. Luckily the hole is more than large enough to easily fit everything. The tightening torque is 8Nm

Assembling The Rest

Now you can inser the other sides of the linkages. Again, I used the molykote 111 silicone compound  on rubber/plastic parts and also used the ball joint tool again for inserting them.

The driver's side linkage goes below the passenger side linkage (at least on LHD vehicle that I have)

As can be seen in the picture above. The driver's side goes over the drive shaft backwards in resting position. This is important, because it gives a more straight connection to drivers side linkage which should provide better connection. As the driver's side wiper is larger, this would improve the linkage life.

Also, after installing the motor/frame in position run wipers once from inside the car and let it come to rest position. Make sure that all the arms are lined up as seen on the picture above. Otherwise it would mean that you made a mistake somewhere.

Now you can go backwards and do reverse of the removal for the wiper frame/base. I cleaned the wiper motor connectors with contact cleaner and then used contact grease on them before installation just to make sure that it lasts forever.

The tightening torque for wiper frame/base to car body is only 5Nm!

Assembling Wiper Arms

If you forgot to install the water deflector. Do it now! The wiper arms should be installed with 25mm +/-10mm from the water deflector. The distance is measured from the wiper ends as seen in the picture below with mark A

The wiper arms should be torque tightened to 20Nm.

I have first tightened the arms just enough to adjust the position and made sure that they are at correct position before tightening to torque. Because once it is totally tightened, it is difficult to remove and re-adjust.