940 headlights very dim with age

[Laney760]

I know there have been some threads long ago on how to improve old 700/900 headlights, I think they lose their reflective qualities?

Mine have become quite dire now, driving on unlit roads is now quite a slow nightmare

Is it worth messing about trying to improve them and if so how? Do I recall somebody cleaning the reflective parts with toothpaste? Or is it best to swallow and buy a new pair, where might be cheapest? I see there have been some for sale on the forum but I don't want to take the chance that somebody else's secondhand ones might be slightly better than mine!

Thanks

[Laney760]

Just found this, I think all my bulbs are from the 'Aldi' multi-sets, might give these Nightbreaker bulbs a try. Any tips on cleaning the reflectors anyone please?

Originally Posted by Forrest

+1 for Nightbreaker bulbs in place of both the auxiliary H3s and the main H4s. Also take the opportunity to dismantle the lamp unit, clean the reflectors (if they're the sort you can clean) and unseize the adjustment mechanism then once reassembled align the beams properly. I've done this on one of my 940s and it makes a huge difference at night. Must get around to doing the others.

If I were going to add further lamps, which I'm inclined to think are not necessary, I think I'd try to modify a radiator grill to incorporate them rather than bolt them onto the bumper.

http://www.volvoforums.org.uk/showthread.php?t=254696

[Paul240480]

Common fail on 200's and phase 1 V70's this. I tried chromed tape on a V70's lights. Still failed the test so bought some cheap replacements to get it through.

On my 200, just this year prior to the test I bought a set of replacement reflectors from parts for volvo. Certainly not a bank breaker in cost. These were quite easy to replace too. Took it to a garage that doesnt charge for headlamp alignment & test sorted

Have a look on PFV, see if they do reflectors for 9's maybe? Hopefully yours aren't sealed units?

[Laney760]

Cheers Paul. They look like sealed beams but I distinctly remember members on here discussing cleaning the reflective parts?

[loki_the_glt]

They are definitely NOT sealed beams: the lamps are a mix of H4 and H1 halogens (or equivalent) and the reflectors are IIRC accessible by removing the lens.

There have been threads about re-silvering on both this and the 200-Series sections but reports of the effect are mixed.

It might be worth removing the glasses and soaking them in washing-up liquid and hot water to get rid of any algae that's sapping the light output. Dry the glasswork thoroughly before reinstalling. Also check that the lampbulbsa re properly seated in their housings.

[Laney760]

Thanks Loki, I will try this next week when I am off work, they really are very bad now and yes, one does have algae inside but they are both equally dim, the one with and the one without algae!

[Brendan W]

While the wash rinse repeat is going on it might be an idea to stick a voltmeter across the bulb pins under load. Earth points, unlike Volvo owners, do not improve with age. I would be aiming to see no more than half a volt below the battery terminal voltage, motor idling.

[Laney760]

Originally Posted by Brendan W

While the wash rinse repeat is going on it might be an idea to stick a voltmeter across the bulb pins under load. Earth points, unlike Volvo owners, do not improve with age. I would be aiming to see no more than half a volt below the battery terminal voltage, motor idling.

Thanks for that Brendan

[TonyS9]

Yeah its worth checking the voltage, crimped loom connections will corrode and get resistive. This can happen anywhere, its not restricted to earth points. neg and positive joints contribute to overall voltage drop, which gets higher (more drop, less voltage available) the more load there is. The big drop in my loom was caused by the crimped battery connections to the starter cable, in older cars these were lead moulded.

The reflectors are very delicate, if there is corrosion they need resilvered which costs more than new reflectors (aluminium coated). Any cleaning is likely to make them worse IMO. If you can get new reflectors go for that. New lenses also look nice too, really lift the car.

[Laney760]

Thanks TonyS9

Just checked out the toothpaste, apparently that is for faded plastic lenses. Apparently many of these commercial plastic lens restoring fluids are basically just watered down toothpaste