Could anyone tell me whether the difference between RHD and LHD headlights is all in the glass - or are the reflectors and bodies different too?
Thanks.
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A lot depends on the design. Certainly some years ago it was just the glass pattern. Now I'm not sure.
But all the ones I've seen recently are one unit anyway, with the glass and reflector and aligned and sealed unit.
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Thanks Martin,
In particular, this is for an elderly Mercedes W124 series where the glass is separately replaceable. Unfortunately, the glass is perfect, but the reflectors have seen better days :-( Complete headlight units can be obtained quite reasonably from several German suppliers (all those Stuttgardt taxis!), but obviously they're the wrong handedness. If the difference is only in the lens, then Robert's your mother's brother.........
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I think that LHD and RHD headlights 'point' to opposite sides of the road.
At one time you used to have to put black sticky triangles on RHD cars in France.
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I think that LHD and RHD headlights 'point' to opposite sides of the road.
But do they? Nearly all cars I have ever had simply dip their headlights, but they remain pointing staright forwards.
The only exception was a 1947 Triumph which had the old Britsh dipping system,, long outlawed; - The offside lamp extinguished, the nearside had a tilting reflector activated by a solenoid, which pointed the beam downwards and to the left.
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I'm sure the lamps will be handed as well as the lens. Cross reference the part numbers with a dealer or GSF / ECP for a difinitive answer
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Long ago in the days of 7" circular headlights with separate bulbs the LH/RH dip was achieved by a combination of position of dip filament in the bulb envelope and glass optics. You could buy diffrent bulbs for LH use abroad.
I would look carefully at the existing reflector and glass set up. Can you operate the headlights with the glass removed? If so you should be able to determine if the reflector or the glass does the does the deflection. Remember, it could be the glass that does the vertical cutoff and the reflector does the horizontal deflection, just to confuse the issue. or the other way round ?!
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pmh (was peter)
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In most cars from the 70's to mide early 90's the dipping was dont by the glass in the lens. The lens throws up (or diverts) a triangle or peak to the left (on right hand drive cars) . Get anywhere nera modern cars tho and its a combination of lens, reflector design and bulb shrouding. Mostly very complex CAD reflector design. Not to mention the move to "projector lenses"
what ever happened to sealed units?
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TourVanMan TM < Ex RF >
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>> I think that LHD and RHD headlights 'point' to opposite sides >> of the road. But do they? Nearly all cars I have ever had simply dip their headlights, but they remain pointing staright forwards.
Headlamps on dipped beam should throw more light to the nearside. If you get wrong-handed ones that throw the extra light to the offside, you will dazzle people and also fail the MoT.
See diagram here:
www.dvtani.gov.uk/vehicletesting/viewstage2.asp
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You can pass an MoT with plastic tape/beam deflectors on the headlights of LHD design.
So maybe just buy the LHD headlights anyway and keep retaping every 6 months. You will loose the kick up pattern on the LHS.
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pmh (was peter)
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Doubt if this true because the tape is there to stop the "wrong" dip pattern blinding other motorists. It doesn't replace the necessary pattern to where its needed. In other words it restricts the light output not re directs it.
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Tis true!
not a reason for failure provided........
www.ukmot.com/1-6.asp
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pmh (was peter)
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Sorry,
Have been to my mot man and he says almost certain failure because the correct beam pattern will not be there. Which is what I thought too.
Headlamp needs to have a defined beam pattern with a kick up to the left. (to the right on lhd cars) as per the beam pattern info posted earlier. The tape/deflectors merely cancel this "kick" to avoid any glare but do not replace it to the opposite side.
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Which bit of this doesn't he agree with?????
Right hand dip headlamps can be temporarily altered for use in the UK by fitting masks or converter kits which remove the beam 'kick-up' to the right A headlamp altered in this way is not a reason for rejection, if a. the headlamp aim is not rejected for the reasons listed under diagram 1 (except that the top of the beam image will be a straight line) b. the light output is not unduly reduced- not usually a problem with commercially produced kits c. the mask or converter is securely attached.
My understanding that this is taken directly from the Official Testers Manual.
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pmh (was peter)
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Older cars, particularly those with the old 7" sealed beam round headlamps, don't have a dip beam like modern units. In these older headlights the dip filament is offset and the dip beam is displaced down and to the left - but no kick up. It's a 'defined beam pattern' so they happily pass the MOT.
JS
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Headlamps on dipped beam should throw more light to the nearside. If you get wrong-handed ones that throw the extra light to the offside, you will dazzle people and also fail the MoT. See diagram here: www.dvtani.gov.uk/vehicletesting/viewstage2.asp
That's interesting - thanks. I've never had a car with the "kick-up" anywhere - too old I suppose.
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>>That's interesting - thanks. I've never had a car with the "kick-up" anywhere - too old I suppose.
I doubt it Cliff - don't you have a Volvo?
The kick-up disappears on full beam, and tends to become more faint as headlight glasses become dirty (on the inside!), and the reflector lose efficiency. IIRC, the pattern's absence on a headlap which should display a kick up (I think they have E or E1 marked on them, but it has been along time, and I can't quite remember) is in itself a valid reason for failure.
Number_Cruncher
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see the link and quote above from Testers Manual.
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pmh (was peter)
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Just to get a different angle on this - what is wrong with the current reflectors? If they need re-plating then in a lot of instances this is possible.
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Mike Farrow
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Can you get reflectors as inserts? You could for BMWs of that era.
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Thanks, Mike - I'll look into that :-)
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If the reflectors are mechanically intact you could probably get them Vacuum Coated, though you will probably have to hunt around for somewhere that can do it for you.
If they are now completely unobtainable then it would be worth the trouble of getting this done.
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On the old Dafs dipped beam was just a V shaped pattern. There was a little switch on the bulb holder which altered the position in which the bulb could be fitted. It just rotated the bulb enough to give a left or right handed beam pattern.
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