Front headlamp lens seal?

[e500.org]

My front headlamp lenses have recently been letting in water after a car wash, the drivers side being the worst. The water normally dries up with the weather and engine heat reasonably quickly but recently given the cooler weather, water is still in the lens the next day after a car wash. Given the car will be going into the garage for work, I would like to rectify this issue at the same time. I noticed a headlamp seal on EPC, A0018262980, which I may order a pair of - would this resolve my issue? After speaking to my local garage, they have recommended to remove the headlamp lens and re-seal the unit using a thin bead of windscreen sealant to ensure a watertight seal. This is theory sounds like a good idea but it would be great to also hear from other members and whether they have experience of water getting into headlight lenses - I assume this method plus a new headlamp seal would probably be the best way forward? A0018262980 seems readily available on eBay, I hope it can be ordered directly from MB. Many thanks in advance.

 

[r44raven]

I recently fitted a brand new complete headlamp unit to my 500E, only to find, like you, it leaked water when washing the car. I assumed it was the seal, but by slowly going around the edge of rhe headlamp glass with a high pressure air line I was able to pinpoint a small area of the "silicon" seal that was leaking. You need to do this while there is "leaked" water inside the lens, because at the point where the air blew through the area of the leak, it disturbed the water droplets inside the glass kens! A close look revealed that for a short length of about 2 centimetres, the original silicone seal had not been applied very thoroughly. A very thin application of silicon at that point cured the problem. I didn't need to dissemble or remove the unit.

 

[e500.org]

I recently fitted a brand new complete headlamp unit to my 500E, only to find, like you, it leaked water when washing the car. I assumed it was the seal, but by slowly going around the edge of rhe headlamp glass with a high pressure air line I was able to pinpoint a small area of the "silicon" seal that was leaking. You need to do this while there is "leaked" water inside the lens, because at the point where the air blew through the area of the leak, it disturbed the water droplets inside the glass kens! A close look revealed that for a short length of about 2 centimetres, the original silicone seal had not been applied very thoroughly. A very thin application of silicon at that point cured the problem. I didn't need to dissemble or remove the unit.

Thanks Stephen, appreciate the input and I will look into that.

 

[gsxr]

+1 on what @r44raven said. The issue may be a leak at the glass-to-frame adhesive, not the foam gasket from lens frame to housing.