How much should my euro lights move up and down?
 

Euro headlight owners,
I recently connected one of my vacuum euro lights to the vacuum system but noticed that the beams don't really move all that much when the switch is played with. With my car pointed at a wall, I can see the light move up and down just a few inches, but it is hardly noticeable when the light is actually aimed at the road. So, how dramatic an effect should the vacuum adjustment have? Do I have my light aimed wrong or something? Is there not enough vacuum getting to the lights? The vacuum source is the front nipple on the main vacuum line going from the vacuum pump to the brake booster. The vacuum switch is located where the speaker fader used to be. This should give you an idea of how much vacuum tubing the headlight system is using. All in all, were pretty disappointing. I hope there's something wrong that I can fix.

Alex

Alex,

The purpose of the movement is to avoid shining your lights up and off the road (and into oncoming traffic/driver's eyes) when the trunk is loaded with stuff. So, the angle of movement is not really that great, but if you park about 100 ft. from a "target" and, at night, run the switch up and down, you will see a readily perceptible range of motion. Your TD has the hydraulic system for keeping the car level under varying loads, like my 190E 2.3-16 (actually my son's now, just hard for me to say that after nearly 16 years and 200k miles together) so the available range is not needed. The light control switch therefore has one stop on the raise the lights side of the normal position (the one you make the static aim from).

At close range (a foot or two) the angle the lights sweep through seems trivial, and it is (at less than half a foot of vertical movement), but with high beams on at 100 or more feet, the range is pretty noticeable, like maybe 20 ft. vertically. Hope this helps, Jim

Jim,
Thanks, but unfortunetely, with the lights shining down a road, there is no noticeable difference when I play with the switch. Oh, and it's a sedan, not the wagon.


Alex

Alex:

FWIW, when I adjust the Euros on my w124 I see a big difference- actually see the low beam pattern moving out from or back toward the car with each click of the switch, and reflectors lighting up further down the road that I could only dimly see before. So the low beam movement is quite visible. For the hi beam measure, there is a T intersection several blocks from my house. When I put on the Hi beams, the adjustment range shows on the house at the base of the T. At lowest setting, the base of the house up to the middle of the first floor window shows the white band of the high beam. At the highest setting, there is a dark band along the base of the house, and the white band of hi beam is elevated to between the 1st and 2nd story windows.

Do you have the check valve installed between the vacuum source and the adjustment switch to keep the vacuum from bleeding back? Or maybe there is a leak from only having one light hooked up? Something doesn't sound right.

John,
No, I don't have any check valves installed in the headlight vacuum system. I should put it somewhere in-line between the vacuum source and the switch?

Alex

Alex:

Yes, their needs to be a check valve. Here is the info from the Star article on installing the valve:

"First, use a short piece of rubber hose to connect the vacuum line to the plug on the back of the right headlight. Run the hard vacuum tubing under the fender joint back to the battery then beneath the cowl air intake over to the brake booster area. Run a similar line from the back of the left headlight to the brake booster area; join them with a Y or T-fitting. Now to get the vacuum line through the firewall. Under the cowl, on the firewall just right of the brake booster is a rubber grommet with several lines through it. Using needle-nose pliers, carefully pull out one of the unused nipples, then feed a length of vacuum tubing from the Y through the nipple.

Inside the car, pull the headlight knob off its shaft, and undo the 24-mm nut holding the panel; wiggle out the panel, left side first. The vacuum lines will run behind the instrument cluster, so you need to get in there. Pull up the floor mat behind the brake pedal, and unclip the speedometer cable clamp so it can move. Slip the wire hooks in on each side of the cluster, and ease it part way out, right side first. Unscrew the speedometer cable connection, and unplug everything else. Remove the cluster entirely, then reach in (right of the speedo cable) with long pliers to pull through the new vacuum line. This line must be long enough to reach the new level control switch near the headlight switch.

Your vacuum source will be the economy gauge line, which you pulled off the back of the instrument cluster. Install a tee in that line and run the new line to the level control switch, with a check valve to allow the vacuum to work but to prevent backflow; the black side of the check valve must be toward the vacuum source (suck it and see). If your car has no economy gauge, use another convenient vacuum source.

TXBill:

I would never aim my lights at their house while they are asleep! I make sure I can see them through the window trying to watch their big screen TV, which acts as an additional reflector for light aiming. ;) :p

Hmm...... vacuum sucks so that mean that if I put my mouth on the side of the check valve facing the vacuum source, I should be able to suck but not blow? Wow, that sounded weird..........

Alex

I ordered two vacuum check valves from FastLane. Unfortunetely, the sent me two of the same one. Also, I can neither suck nor blow through either side. Does anyone know what this check valve does, where it goes, and if it would work for my headlight application? Thanks. It's blue and black, part number 123 800 00 78

Alex

On mine, the check valve is placed between the roller height adjustment switch, and a T fitting installed into the vacuum gauge line. The blue side is closest to the 4 position roller switch by the headlight switch, the black is closest to the vacuum line on the gauge in the instrument cluster.

Just as a follow up clarification, it goes in between the height adjustment switch and the vacuum source right? And the black half of the valve is facing the source? I have it this way and unfortunetely, it still isn't all that great. Maybe my lights are aimed improperly? Maybe they're aimed too low. Anyway thanks, I'll play around with it.


Alex