moisture in headlight
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Joined: Oct 2006
Posts: 49
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From: olivebranch Mississippi
2000 E430 sport
moisture in headlight
Finally got e430 back from autoshop where a gentleman took out by front bumper. Both headlights, which where yellowed all up, cracked - lucky me. Instead of replacing the OEM, I asked the bodyshop to use the DEPO clear projector style since they were cheaper and visully more appealing. They agreed and put them in. Problem is the drivers side are "fogged" up, where as the other side perfect. The mechanic (whom I know) looked at the headlight and thought it was a manufacturing defect.The company we got them from e-mailed me telling me it was probably due to a breather hole not being unplugged. Anyone heard of this, and if is true, where these "breather holes" are so I can unplug myself. Thanks.
MBWorld Fanatic!
Joined: Jan 2004
Posts: 5,942
Likes: 178
From: Seattle WA
99 E320
the breather tube is a short stretch of rubber hose, exiting the rear of the
headlight assembly (towards the top, as I recall). about 3" long, the single
tube ends in a "T" with dual breathing ports. basically, it just dangles in the
air.
direct water entry: comes through the main seam which may be insufficiently
sealed. this seam is around the perimeter between gray housing and clear
outer lens. it is covered by a figure-8, rubber rand/gasket. if water entry is
here, I'd suggest windshield sealent (more viscous and thin), then follow up
with application of RTV silicone (thicker and lays wider bead)
vapor/condensation: warm(er), moist air condenses on cold, dry surface.
yes, breather/vent could be partly the cause. but I'd do whatever I could
to move moist air from beneath the hood. this happens mostly after rain
and hot engine steams ground moisture....which enters headlight as vapor
and condenses on inside of the lens. this may occur also after a car wash.
vacate moist air, speed up air flow, expel moisture (dry it out quicker),
heat the lens...are all part of brainstorming ideas. simple physics. natch,
some are more practical to execute than others.
headlight assembly (towards the top, as I recall). about 3" long, the single
tube ends in a "T" with dual breathing ports. basically, it just dangles in the
air.
direct water entry: comes through the main seam which may be insufficiently
sealed. this seam is around the perimeter between gray housing and clear
outer lens. it is covered by a figure-8, rubber rand/gasket. if water entry is
here, I'd suggest windshield sealent (more viscous and thin), then follow up
with application of RTV silicone (thicker and lays wider bead)
vapor/condensation: warm(er), moist air condenses on cold, dry surface.
yes, breather/vent could be partly the cause. but I'd do whatever I could
to move moist air from beneath the hood. this happens mostly after rain
and hot engine steams ground moisture....which enters headlight as vapor
and condenses on inside of the lens. this may occur also after a car wash.
vacate moist air, speed up air flow, expel moisture (dry it out quicker),
heat the lens...are all part of brainstorming ideas. simple physics. natch,
some are more practical to execute than others.
Super Member
Joined: Jun 2008
Posts: 835
Likes: 2
From: Bay Area, CA
09' E320
If similar to the OEM's gently squeeze the two halves of the lense closed while releasing the 2 clips holding them together. When the clips are released, pry apart and open up a 1/8" gap with a screwdriver. Then turn the lights on. Creates plenty of heat to evaporate the condensation.
