Headlight travel range
01-17-2004, 10:54 PM
#1
Rennlist Member
Thread Starter
Headlight travel range
I recently picked up an early 928, and found that the headlights were not aimed properly. I'm pretty much certain that the phillips screw adjusters do not have enough travel to help with this. The beams are pointing far above where they should. If I'm 6 feet away from a wall, the low beam cutoff is a good 6-8" above the center of the lamp itself. 
I also noticed that the lights retract into the fender further than they should. When the lights are extended, I can't pull them forward any further, though the light and the little pod have a little play in them to the tune of ~2mm front to back. The base does not have this play, just the pod. Nichol's site mentions a detent spring; if this were the problem I suppose that I would be able to move the lights further forward from the extended position, but this does not seem to be the case.
I will track down the 2mm play tomorrow, but here's the part that's bugging me. It seems that the lights move smoothly through their full travel. I disconnected the link from the motor and the lights seem to have a fair amount more travel than is really necessary... I can pull them far enough forward that they point far too low, and I can let them back against the internal stop and they seem to drop further in the fender than what seems right. What this means is, the only thing holding the lights in the correct open or closed position is the motor. Is this correct? Or do I have to adjust the motor height to get the range of travel correct, then adjust a stop somewhere?
The service manual really has no specific information on how to adjust this. I complained about how incomplete the manuals I received on CD are in another thread here. The closest thing I could find to useful information on this topic in the manual is that the lower right picture on P. 50-3 seems to show an adjustable lower stop... but there is very little adjustment, judging by the picture. BTW, this is in a section on replacing the front end, and the headlights are only mentioned in passing.
So it seems that I'm left to guess for myself(and post here) regarding the best way to set this up. Unless someone has any better information for me, here is what I plan to do tomorrow:
1) Turn on lights then remove ground strap, so that headlight motor is in normal "up" position.
2) Remove pods from lights
3) Set vertical adjustment(small phillips screw explained in owner's manual) to approximately the middle of their range
4) Loosen motor mounting screws and move motor up until headlights are pointing pretty close to where they are supposed to point and retighten
5) Using **** on motor, move it through one complete cycle, down then up to make sure there is no binding.
6) Reconnect battery and test.
7) Adjust to taste(I can do the fine adjustment in my sleep... that's the easy part)
8) Put pods back on
I suppose that another alternative is to line up the retracted headlights as well as possible in the opening, so that it "looks right" and go from there....
Ideally, I would like to set it to "factory spec" but if there is such a spec it seems unavailable to mere mortals such as myself...
Any help with this would be appreciated... I don't have a lot of time for trial and error, as I am currently in the process of going through the entire car, changing fluids, hoses, etc. I want to get this right though so I can test the car after dark.
Thx...
I also noticed that the lights retract into the fender further than they should. When the lights are extended, I can't pull them forward any further, though the light and the little pod have a little play in them to the tune of ~2mm front to back. The base does not have this play, just the pod. Nichol's site mentions a detent spring; if this were the problem I suppose that I would be able to move the lights further forward from the extended position, but this does not seem to be the case.
I will track down the 2mm play tomorrow, but here's the part that's bugging me. It seems that the lights move smoothly through their full travel. I disconnected the link from the motor and the lights seem to have a fair amount more travel than is really necessary... I can pull them far enough forward that they point far too low, and I can let them back against the internal stop and they seem to drop further in the fender than what seems right. What this means is, the only thing holding the lights in the correct open or closed position is the motor. Is this correct? Or do I have to adjust the motor height to get the range of travel correct, then adjust a stop somewhere?
The service manual really has no specific information on how to adjust this. I complained about how incomplete the manuals I received on CD are in another thread here. The closest thing I could find to useful information on this topic in the manual is that the lower right picture on P. 50-3 seems to show an adjustable lower stop... but there is very little adjustment, judging by the picture. BTW, this is in a section on replacing the front end, and the headlights are only mentioned in passing.
So it seems that I'm left to guess for myself(and post here) regarding the best way to set this up. Unless someone has any better information for me, here is what I plan to do tomorrow:
1) Turn on lights then remove ground strap, so that headlight motor is in normal "up" position.
2) Remove pods from lights
3) Set vertical adjustment(small phillips screw explained in owner's manual) to approximately the middle of their range
4) Loosen motor mounting screws and move motor up until headlights are pointing pretty close to where they are supposed to point and retighten
5) Using **** on motor, move it through one complete cycle, down then up to make sure there is no binding.
6) Reconnect battery and test.
7) Adjust to taste(I can do the fine adjustment in my sleep... that's the easy part)
8) Put pods back on
I suppose that another alternative is to line up the retracted headlights as well as possible in the opening, so that it "looks right" and go from there....
Ideally, I would like to set it to "factory spec" but if there is such a spec it seems unavailable to mere mortals such as myself...
Any help with this would be appreciated... I don't have a lot of time for trial and error, as I am currently in the process of going through the entire car, changing fluids, hoses, etc. I want to get this right though so I can test the car after dark.
Thx...
01-18-2004, 12:13 AM
#2
Nordschleife Master
You've basiccally got it. Sounds like you need to move the motor up to get things right. Couple of things to consider:
You may need to adjust some stops inside the fender. When lights are up, the motor will hold the lights against them. Then they don't wobble when hitting bumps.
There's an adjustment that may need to be made at the bottom of the headlight frame. There's is a shaft that holds the light "bucket" from tipping. The purpose is to allow up/down movement for Euro headlights which hav a manual fine adjustment. For US cars there is a solid shaft put in. The front end has a ball on it that fits into some plastic fingers and can be in two (or maybe three) positions. If this has slipped back, you'll never get the headlights adjusted right as there isn't enough adjustment in the screw/spring system.
There are also adjustments for side-to-side (clamps on shaft) and fore/aft of the headlight and a bit of up-down (bushing where shaft goes through body) so you can get the headlight juuust right.
You may need to adjust some stops inside the fender. When lights are up, the motor will hold the lights against them. Then they don't wobble when hitting bumps.
There's an adjustment that may need to be made at the bottom of the headlight frame. There's is a shaft that holds the light "bucket" from tipping. The purpose is to allow up/down movement for Euro headlights which hav a manual fine adjustment. For US cars there is a solid shaft put in. The front end has a ball on it that fits into some plastic fingers and can be in two (or maybe three) positions. If this has slipped back, you'll never get the headlights adjusted right as there isn't enough adjustment in the screw/spring system.
There are also adjustments for side-to-side (clamps on shaft) and fore/aft of the headlight and a bit of up-down (bushing where shaft goes through body) so you can get the headlight juuust right.
01-18-2004, 02:36 AM
#3
Rennlist Member
Thread Starter
Thanks Glen, I'll look into that tomorrow. I'm guessing that most of the gross adjustments are fine. Right now the motor is disconnected and if I rotate the lights forward just a bit, lifting the top edge of the lights maybe 1" they seem to line up perfectly with the opening.
I think I figured out what happened to the lights to begin with. I only have repair info from the last 3 years or so... including a mail order receipt from 928 international.
It looks like he had a local "discount" repair shop R&R the radiator, brought it to one of the big radiator shops in San Jose, and had them replace the tanks... cash & carry.
My guess is that at that time, the mechanic had to loosen or remove the headlight motor to get the radiator out, and wasn't smart enough to see that it was on a slotted mount, mark it before loosening it, fix it after bungling it, or show any other sign that he had any business working on a car like this. In fact, he didn't even write the mileage or date on the work order, the earliest dated W.O. I have. I had to get the date from the separate receipt for the radiator. 
Now here's the kicker... Judging from the later receipts that I DO have with mileage entered, this guy drove it this way, for at least 1000 documented miles and I'm guessing another 1500 for the 19 months I can't account for. And there was no mention of any problem with the headlights on any of the later work orders! They lit up so he though they were OK.
I'm glad this guy only had the car 4,000 miles... he had no business owning a car like this(except to sell it to me, of course).
Anyway, enough ramblin. I'll let y'all know what I find.
S
I think I figured out what happened to the lights to begin with. I only have repair info from the last 3 years or so... including a mail order receipt from 928 international.
It looks like he had a local "discount" repair shop R&R the radiator, brought it to one of the big radiator shops in San Jose, and had them replace the tanks... cash & carry. My guess is that at that time, the mechanic had to loosen or remove the headlight motor to get the radiator out, and wasn't smart enough to see that it was on a slotted mount, mark it before loosening it, fix it after bungling it, or show any other sign that he had any business working on a car like this.
In fact, he didn't even write the mileage or date on the work order, the earliest dated W.O. I have. I had to get the date from the separate receipt for the radiator. Now here's the kicker... Judging from the later receipts that I DO have with mileage entered, this guy drove it this way, for at least 1000 documented miles and I'm guessing another 1500 for the 19 months I can't account for. And there was no mention of any problem with the headlights on any of the later work orders! They lit up so he though they were OK.
I'm glad this guy only had the car 4,000 miles... he had no business owning a car like this(except to sell it to me, of course).
Anyway, enough ramblin. I'll let y'all know what I find.
S
01-19-2004, 12:51 AM
#4
Rennlist Member
Thread Starter
Thanks Glen...
Yes, the ball had popped out of the little plastic finger-socket on both sides. Fixing that made up half of what I needed, raising the motor enough to make the lights snug against the front stops did the rest. After those 2 changes they are straight enough that I can focus on other issues for a while. Still not where I want them, but I have other things to do on the car before I "fine tune" them to my liking.
S
Yes, the ball had popped out of the little plastic finger-socket on both sides. Fixing that made up half of what I needed, raising the motor enough to make the lights snug against the front stops did the rest. After those 2 changes they are straight enough that I can focus on other issues for a while. Still not where I want them, but I have other things to do on the car before I "fine tune" them to my liking.
S