Probably about 12 months ago, I replaced the existing sealed beam headlights with a pair of Wipac halogen, glass reflector, conversion units.
Over time the inside of the lenses have become "cloudy". Has anyone else experienced this?
It is definitely not misting, but a slightly opaque coating on the glass internally. The car is garaged.
I have removed the lights and brought them into the house to check if it's temperature related, but they remain cloudy. Trying to clean the inside of the glass could well do more harm than good - a bit like keyhole surgery!
Wipac halogen conversion.
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- geoberni
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Re: Wipac halogen conversion.
Basil had such a conversion when I brought him.
He is also garaged.
I subsequently replaced the Halogen lamps with LED items.
When I did so, I realised the Glass was coated with a smoky grey residue, which I carefully wiped out with a piece of soft cloth and a long screwdriver as the manipulating implement.
I haven't noticed it return.
He is also garaged.
I subsequently replaced the Halogen lamps with LED items.
When I did so, I realised the Glass was coated with a smoky grey residue, which I carefully wiped out with a piece of soft cloth and a long screwdriver as the manipulating implement.
I haven't noticed it return.
Basil the 1955 series II


- svenedin
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Re: Wipac halogen conversion.
To clean the inside of the glass you could use a tool like a pair of surgical locking forceps. Clamp a "swab" of soft cloth moistened with isopropyl alcohol in the forceps and you can then clean the inside of the glass. Such tools are readily available and not that expensive. I think the misting is caused by some kind of residue that burns off the bulb when first used.
Stephen
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen
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Mervin
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Re: Wipac halogen conversion.
Thanks both.
I did clean the inside of the lenses using a microfibre cloth, pushed throught opening, and stirred it around using the handle of a wooden spoon.
That did the trick. I have temporarily refitted sealed beams and will try again in due course. If they cloud up again, it's back to sealed beam units.
I did fit Philips Ultinon Classic l.e.d. lamps rather than the supplied halogen. I wonder?
I did clean the inside of the lenses using a microfibre cloth, pushed throught opening, and stirred it around using the handle of a wooden spoon.
That did the trick. I have temporarily refitted sealed beams and will try again in due course. If they cloud up again, it's back to sealed beam units.
I did fit Philips Ultinon Classic l.e.d. lamps rather than the supplied halogen. I wonder?
- svenedin
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Re: Wipac halogen conversion.
I haven't noticed it with LED bulbs which I currently have installed. I did notice it with the halogens previously installed.Mervin wrote: ↑Thu Jan 15, 2026 10:45 am Thanks both.
I did clean the inside of the lenses using a microfibre cloth, pushed throught opening, and stirred it around using the handle of a wooden spoon.
That did the trick. I have temporarily refitted sealed beams and will try again in due course. If they cloud up again, it's back to sealed beam units.
I did fit Philips Ultinon Classic l.e.d. lamps rather than the supplied halogen. I wonder?
Maybe it's not fumes from the bulb but something getting in from outside? Or is it something coming from the reflector? It's important the rubber dust boots are fitted properly to prevent muck entering.
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen
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mike1864
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Re: Wipac halogen conversion.
Stephen's observations would suggest running new halogens (including any spare) for an hour or so in the open air; it can't do any harmsvenedin wrote: ↑Thu Jan 15, 2026 1:06 pmI haven't noticed it with LED bulbs which I currently have installed. I did notice it with the halogens previously installed.Mervin wrote: ↑Thu Jan 15, 2026 10:45 am Thanks both.
I did clean the inside of the lenses using a microfibre cloth, pushed throught opening, and stirred it around using the handle of a wooden spoon.
That did the trick. I have temporarily refitted sealed beams and will try again in due course. If they cloud up again, it's back to sealed beam units.
I did fit Philips Ultinon Classic l.e.d. lamps rather than the supplied halogen. I wonder?
Maybe it's not fumes from the bulb but something getting in from outside? Or is it something coming from the reflector? It's important the rubber dust boots are fitted properly to prevent muck entering.
Stephen
And of course keep fingers off the bulbs.
- svenedin
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Re: Wipac halogen conversion.
Yes I thought that too. A quick "burn off" of a new bulb in the open air. I wonder whether any quick puff of smoke is visible? Also serves as a test of the bulb before putting everything back together.
Stephen
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen