The plastic arch liners on the front of the car are great for protecting the wiring that run behind them and for keeping damaged from stones etc away from the wings. They do cut down on a lot of corrosion.
However they also collect a lot of mud etc.
The bottom of the arch liner is where the water that runs along the sills pours into and if the cars equiped with a sliding sunroof its where the front gutter pipes exit as well.
This means lots of mud, leaves and other debris builds up over time. It can become surprisingly thick.
What does this mean? Well aside from carrying about and extra 5 or so kg's of mud on the car, this mud traps moisture right against the metal, this makes it rust which isn't what you want. Also it can prevent the sunroof drain channels emptying whcih can cause sunroof leaks.
So what do you do? You remove the arch liners and clean out all of the mud.
Tools you need a T20 screwdriver and if you struggle with the push clips then a hammer/flat blade screwdriver can help to lever them out.
The arch liner is held in by T20 screws and plastic push clips. Meganes and Lagunas have 2 T20 screws at the bottom and 19's etc have 1 T20 screw. There is then a few plastic push clips that hold the liner in place
Heres the push clips
here is the twin T20 screws on a megane
You can leave the wheel in place and the car on the ground to get the liners off but it is easier with the wheel off.
Heres the liner
When you remove the liner you will more than likely be confronted by something like this
Yes thats all mud and leaves, 14 years its had to gather there.
Further up you can see if you have a sunroof the drain tube,
As you can see theres a flap valve which is only fitted on newer cars like the megane and laguna, earlier cars are just straight tubes. The flap traps a lot of debris so my advise is remove it and leave it as an open tube.
valve with some dirt
after a clean
Use a screwdriver to clear the tube if its blocked. Pour water around the sunroof and it should pour out of the cleaned tubes freely.
A hose is the best thing to wash away the built up dirt, pull the majority away with your hands first. If you use a scraper be very carefull you don't scratch/gouge the metal or it will rust. When you have cleaned the area it will look very different like this
Now its clean you can put the liner back in. The cars now lighter, less chance of corroding in that area and hopefully the sunroof will not leak anymore. It looks better as well as you can see the build up when you open the door and look forward.
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