Sealed Beam Head Lights

[zulublue]

I have just changed from Halogen to sealed beam units because I keep flooding them in deep water and its rotting the reflector. When I used them tonight for the first time they come on with the side lights but once going to main beam they only improve by about 20% over the side light setting, is this normal or do I have a wiring problem, I know they are dull in comparison to halogens but I was expecting a little more.

Second question, are there such things as Halogen sealed beams?

Mark.

[RobotMan]

It could be said they are called sealed beams because they seal the light in.

That's as good as they get I'm afraid, they are even worse with a dynamo set up, ah those where the days.

[western]

I have just changed from Halogen to sealed beam units because I keep flooding them in deep water and its rotting the reflector. When I used them tonight for the first time they come on with the side lights but once going to main beam they only improve by about 20% over the side light setting, is this normal or do I have a wiring problem, I know they are dull in comparison to halogens but I was expecting a little more.

Second question, are there such things as Halogen sealed beams?

Mark.

if the headlights are coming on with reduce illumination with the sidelights, your vehicle has the dim dip system fitted. or maybe you have a earth fault at the connection to the body behind the front light units.

[Monster]

Hi,

Have you tried the Wipac Crystal halogen conversion kit? It is plastic.

It has the light bend(to dip) molded into the reflector rather than on the glass, like most modern cars, and a clear lens.

http://www.paddockspares.com/pp/DEFENDER/E...Kit_(pair).html

It really improves visibility especially full beam. Not that great on dip though. Got mine from Paddocks and just order some for my other landrover and one for my brothers LR. (Check legality of use though).

Not sure if it was just my LR but i needed to modify the bowl to fit my headlight brace. Being a hybrid i come to expect i need to modify every single part to fit my LR!!

[zulublue]

Thanks all,

Monster are you saying the rear reflector is plastic? if so is the silver reflector part sealed in any way. What I am trying to achive is when I go out and get back late, I dont have to start emptying headlights, if these are plastic I will drill a hole in them for drainage.

[JST]

i changed back to sealed beam for the same reason so would be interested to know if they are plastic backed as it would serve my need as well.

[DaveB]

My 200Tdi came with sealed beams. The best thing I ever did was to replace them with Halogen units. I can actually see where I am going now when it gets dark.

[sgnas]

I have "Wipac" headlight bowls on the 90 and 110. I bought the at a Sortout a while back specifically because the bowls were plastic.

There is still the chance that the Chrome plate will lift off the plastic, maybe more so if you create a defect (hole) and they will certainly dull with muddy water but they will not go rusty

[Monster]

Thanks all,

Monster are you saying the rear reflector is plastic? if so is the silver reflector part sealed in any way. What I am trying to achive is when I go out and get back late, I dont have to start emptying headlights, if these are plastic I will drill a hole in them for drainage.

To be honest i am not sure what the reflector material is made of.

Thought about it after i sent post and it may actually be some sort of metal bonded to the plastic bowl.

The bowl part is definitely plastic as i had to sand it down to fit the headlight cradle that i have.

Was your halogen reflector/bowl made out of all metal? (The ones i removed had plastic bowls)

I have also fitted light guards on mine as the lens is plastic (I think) an i dont want anything cracking or smashing them.

Is it possible to check out at a local lr shop before you buy?

Failing this cant you completely incase the bulb/holder with silicone or some other sort of compound? I find that halogen bulbs are long lasting and you wouldnt have to do it that often!

(I must admit i have no experience of the type of offroading you do).

I would say though worth pursuing as sealed beams i think are a definite step backwards.

"There is still the chance that the Chrome plate will lift off the plastic, maybe more so if you create a defect (hole) and they will certainly dull with muddy water but they will not go rusty"

I think the reflector would have to be shiny to give the maximum reflection as the bulb illumination itself isnt that good on it own.

Cheers

[LR90]

Just replaced one of my halogens for sealed beam after the reflector got too corroded. Quite adequate for the sort of LR speeds I do.

[jwriyadh]

Check the wiring for bad or corroded connections.

Put a voltmeter on the bulb connector and measure voltage delivered to the bulb with reference to the battery negative. It should be close(0.5volt or better) to battery voltage.

If you have significant voltage losses move the voltmeter probe back through the electrical system towards the battery(while lights are on) positive terminal to locate the cause of the losses.

If the voltage losses are spread through the system then you can eliminate them by fitting two 30 amp relays connected to a fused supply on the battery positive. Control the relays with the original headlight feeds, ie, blue/white for main beam and blue/red for dip beam.

Sealed beams can be made to function adequately, but even small voltage losses will reduce their output drastically.

There was even a 75 watt sealed beam that fitted some Rover cars in the dim and distant.

jw

[ThreeSheds]

In answer to an earlier question - no, it is not possible to make a sealed beam halogen (not in the sense of having the filament 'open' in the bowl. The best that could be done is to have a conventional halogen bulb in a sealed reflector/lens assembly. The reason is that the filament is very hot and continuously evaporates into the halogen gas that surrounds it. The halogen gas and the 'envelope' both also have to be very hot to prevent crystalisation of the metal salts on the inside.

Ohh, just found this... Wikipedia explains it better:

In an ordinary incandescent lamp, the thickness of the filament may vary slightly. The resistance of the filament is higher at the thinner portions which causes the thin areas to be hotter than the thicker parts of the filament. The rate of tungsten evaporation will be higher at these points due to the increased temperature, causing the thin areas to become even thinner, creating a runaway effect until the filament fails. A tungsten-halogen lamp creates an equilibrium reaction in which the tungsten that evaporates when giving off light is preferentially re-deposited at the hot-spots, preventing the early failure of the lamp. This chemical transport reaction is based on WO2I2 or WO2Br2 formation at elevated temperatures and its decomposition at high temperatures at the tungsten filament. This also allows halogen lamps to be run at higher temperatures which would cause unacceptably short lamp lifetimes in ordinary incandescent lamps, allowing for higher luminous efficacy, apparent brightness, and whiter color temperature. Because the lamp must be very hot to prevent crystalistaion of WO2I2 or WO2Br2 at the glass surface, the halogen lamp's envelope must be made of hard glass or fused quartz, instead of ordinary soft glass which would soften and flow too much at these temperatures.

phew!

[BogMonster]

Sealed beams always have been and always will be carp. Whether you use them depends on whether you need to drive at night or just need a working headlight to pass the MOT

[FridgeFreezer]

I have the crystal ones and they do fill up with water, but when empty at least I can see where I'm going. They are 100% plastic, the reflector has a shiny coating but isn't metal. If it's a problem, drill a hole in the bottom of the unit to let water out, it needs to be a decent diameter though (>5mm) otherwise it gets blocked up.