VW T4 Instructions
There are a few ways to fit windows. In these van window installation instructions it will give you info on how to fit them the factory way. We believe this is the best way as it hides all the cut edges and gives a much nicer finish inside. This method gives the same finish for Caravelle or Kombi models.
Over the years we have seen how others fit T4 windows. They do so by cutting a hole out and then bonding the window on using a trim to hide the cut marks inside. The problem doing it this way is the window will stick out too far on the outside. Therefore, meaning the seal wont do its job properly of keeping the weather out.
We would only recommend fitting the factory way as it looks much neater. Also, because the window sits right inside the panel you wont have any issues with water ingress inside the van.
From the inside of the van you will see a bonding adhesive/seam sealer fixing your inner panel (or inner lip) and outer panel together. This needs to be removed to enable cutting the outer panel to sit inside the inner lip. This will then hide the cut mark.
We use a special air tool but you can achieve the same result with a chisel and a stanley knife. Go at it nice and gentle, using excessive force will damage the inner lip.
Use a 3mm drill bit and drill some pilot holes from the inside of the van along the outer panel. You will be cutting as close to the top of the inner lip as you can so from the outside. This is so you can see where to cut.
On the outside of the van draw the cut line.
Drill a hole in the corner of the window big enough that you can get your nibbler or jigsaw in.
To cut the hole we use an air nibbler but you could use a jigsaw with a metal blade angled at 45 degrees to the inner lip to cut the panel out.
What you are trying to do is cut the outer panel slightly larger than the inner lip. (see picture below)
Don’t go crazy, try to retain as much material as possible as you will be bonding these 2 skins together later!
Cut the panel like this
Once the panel is cut out you need to dress the metal work back. You will need to remove the last remaining old adhesive/seam sealer from between the panels. Try to get it as clean as you can.
We use a tool for dressing the panels back so it doesn’t damage the paint work on the inner lip. However, you can achieve good results with a round hammer and a small piece wood say 2”x 1” about 8” long and 2 G clamps. You attach the piece of 2 x 1 on the inner lip giving it rigidity (otherwise when you hit the panel it won’t bend back, it just moves around!)
You now need to bond the 2 skins back together we use a spot welder as per the pictures above. The same result can be achieved by bonding the two skins together using the correct PU windscreen adhesive.
Once adhesive is applied between the two skins, you will need to clamp the two skins together. The adhesive will cure in a few hours in the right conditions. This time may vary depending on conditions. To quicken up this process we have used heaters in vans before in the middle of winter and sealed the now new holes in the van to keep the heat in.
You are nearly ready to fit the window. Just remove any rough paint from the aperture. Then, use the glass cleaner/glass primer on a clean cloth to clean where you will be bonding to on the body of the van.
Fit the seal to the window. The lip on the seal goes on the inside of the window. The join is always at the bottom.
Next use the body primer with the large cotton bud supplied (paint and body primer). Apply it to the body work of the van where you will be bonding to.
Apply body primer on the darker band around the circumference of the window.
You are now ready to fit your new window.
Use the window adhesive in a standard caulking gun with the V shape applicator. Hold gun at 90 degrees to the aperture. You need to achieve a good seal. Therefore, start at the bottom and work your way round in 1 motion. Apply the adhesive to the middle of the aperture to avoid adhesive “splurge” when the window is pushed against it.
For best results we clamp the fitted window in for an hour,. This is so it sets nice and close to the inner lip on the inside of the van, and from the outside the window will be flush with the body work.
PASSENGER SIDE SLIDING DOOR
The sliding door is the same process. Although the inner lip is slightly larger so it might be worth drilling a few more pilot holes from the inside. Mark these up on the outside so if you are cutting from the outside you can see where to go.
Please use these van window installation instructions as a guide.
We take no responsibility for your fitting and always recommend using a trained technician if you are in any doubt.
Please use the correct safety goggles, gloves etc
You can also view our van window fitting guide for Volkswagen Transporter T5 or Volkswagen Transporter T6.