Discovery 2 TD5 - fog lamps keep misting up!

[boaterboy]

If you will excuse the pun, please, I've had to replace several fog lamps on my Discovery 2 TD5 because they keep misting up.

Eventually, the glass goes opaque and the reflector bubbles up and rusts.

In the case of the last one, the bulb holder had corroded in!

Any ideas as to how to keep them watertight, please?

[Shackleton]

Can't think why you'd have persistent bad luck unless there was something amiss although I've only been living with fogs for this past winter. Mine have misted once or twice when there's been prolonged driving in torrential rain, but just taking the covers off on a dry/sunny day sorts it out and it doesn't come back. (It's probably important to point out that I've got an extra light fitting per fog lamp, which are sealed to the lamp body only with rubbers, i.e. no sealant, and they're likely to be the source of my misting.)

Are the breather pipes routed up behind the headlamps properly? they can get pulled too tight or at a bad angle which can compress the little rubber seal to the body of the lamp. The wiring is protected by similar hard plastic tubes and imo they're probably the most vulnernable area in terms of water ingress. Mine are sealed with a dab of RTV for that reason.

The black body plastic does become very brittle and can crack in such a way that it'd be easy to miss. One of mine is repaired with epoxy resin.

[boaterboy]

Thank you for your response, Shackleton.

I'm not sure that we are talking about the same design of fog lamp, however?

Mine are about 10cm diameter and mounted in the bumper valance.

There are no covers, as such, to remove - it's quite an exercise to take them off the vehicle from up inside the wheel arch.

I had to remove the whole of the bumper assembly to get at the nearside one which is concealed behind the washer bottle assembly.

Also, there is no evidence of any breather pipes.

The lenses are bonded to the reflector bodies - but I take your point about the use of RTV.