Hydraulic light adjustment

[stevejordan100]

I hope someone can help . I am new to this forum and am currently restoring a 1986 M635CSI . I want to bring this back to as near showroom condition as possible. I have the Hydraulic light adjustment system with the switch down by the right knee. All the pipes have gone brittle and have broken in several places, Can these units be restored if so how, I have been told by BMW this part is no longer available, does anyone have one in working condition or know where I can get one, if the answer to all my questions is no, what is the alternative solution.
I am based in the UK and will post pictures once I find out how to do it

Steve

[ron]

Here is a post I put on a few years ago. As you can see it is a major job to replace. I think I still have a spare unit somewhere.

The h/l adjustment system is a fluid filled sealed system.As you turn the adjuster it pushes the fluid down the pipe which moves the fancy valve on the h/l. Turn it the other way and it reverses.The system is sealed at manufacture and I have tried various ways to refill and bleed it without success.There are no bleed valves fitted which doesn't help. I did replace the unit on my silver Highline and it took a while. Remove steering wheel, panel underneath,w/s wiper motor(gives abit more room),panel above heater fan,panels either side of heater fan,battery,washer bottle and complete headlight units (which require the grill units and front indicators to be removed),centre grill.The awkward bit next.The big grommet by the wiper motor has to be cut and unstuck from the bulkhead( so all the excess sealant that has been put on over the years needs to be carefully scraped off) I think that I sliced it vertically from the top to the wire bundle. The new unit has to come through that hole from the inside of the car and that is a real PITA as the pipes and adjusters have to be at the right angle to go through the hole.Once through,run the pipes to the front where the old ones ran. I then started from the front and allowed enough slack to let the h/l units come out and slowly put everything back together.The pipes are tywrapped to the cable clipping points.The grommet was resealed with black silicon and hasn't leaked!!I was going to swop it on to the red one but it is such a PITA that it is easier to buy a new unit from BMW and do it all over again especially as the pipes get so brittle that they would probably snap.When I do it again I'll take pictures.Regarding manual adjustment for up/down,the valve units can be screwed in and out (on the big milled plastic collar) They are a bit difficult to get at but give a squirt of WD 40 or similar.

This is what it looks like.

[stevejordan100]

Hi Ron
Thanks a million for this, its as I thought, I need a new one. I am quite prepared to put in the work if I can find one. If you have a spare in working order would you like to sell it, if so how much would you want for it.

Cheers

Steve

[stevejordan100]

Hi Ron
The write up on these hydraulic lights for my 635csi m was really informative. I intend to get this working as it was originally. I know you can still buy the unit for the left hand drive cars, so I was thinking of trying to fit this to my right hand car----what do you think
Has anyone done this
Steve

[Mark Shutt]

I've never tried my adjustable headlights, what's the chance they work do the lights need to be on or just ignition or both? I'm curious now!

Mark.

[ron]

.....do the lights need to be on or just ignition or both? I'm curious now.

They are purely mechanical.

[Mark Shutt]

.....do the lights need to be on or just ignition or both? I'm curious now.

They are purely mechanical.

do they work off engine vacuum then?

[Brucey]

they are hydraulic; there is a small (manually operated) pump at one end and a small hydraulic motor at the other, and the system is filled with fluid.

The pictures Ron has posted show a complete system; twirl the knob at one end and the other end moves.

BTW Does anyone know what fluid is used in this system?

cheers

[Mark Shutt]

my "knob" just keeps turning round clockwise with no resistance.. will have to read up on this.

[ron]

my "knob" just keeps turning round clockwise with no resistance.. will have to read up on this.

Pipes are probably broken. The car numbers with the system working is very, very small.

[Mark Shutt]

my "knob" just keeps turning round clockwise with no resistance.. will have to read up on this.

Pipes are probably broken. The car numbers with the system working is very, very small.

I think you may be right, the pipes are very brittle and think I saw cracks in places so chances are they don't which is a shame..

[ron]

Hi Ron
I know you can still buy the unit for the left hand drive cars, so I was thinking of trying to fit this to my right hand car----what do you think

I don't think this would work as the RHD version has to run across the bulkhead behind the engine before it runs forward. The LHD version comes out immediately in front of the driver (L/H) and runs directly forward. I think each pipe would be around 3-4 ft. too short.

Hope this makes sense to you!

[ron]

BTW Does anyone know what fluid is used in this system?

I think it is antifreeze or similar.

[Brucey]

BTW Does anyone know what fluid is used in this system?

I think it is antifreeze or similar.

That makes sense, it presumably needs to have corrosion inhibitors in it.

Re installing a LHD set in a RHD car; I agree the routing is different but I think it could be done in a non-OEM style fashion, eg by running the pipes out through the ECU grommet and then going forwards directly (i.e. along the RH side of the engine bay) from there perhaps?

BTW in the light of Ron's experiences with these systems I have not been optimistic about DIY refurbing them, but upon reflection it must be possible somehow! BTW if it is standard 4mm pneumatic hose there are many different materials available including PTFE amongst other things.

cheers

[miike87]

Even if you replace the lines the cylinders will still be the weak point. They tend to be cracked behind the connection to the lines or next to the seal plug. Getting those fixed is quite difficult. Is the rod in the cylinders still moving if you pull it? If it's struck or hardly moving they are corroded inside.
The knob on the inside could be leaking too. The whole system needs to be 100% sealed to work. Even new replacement systems seem to work only for some years...
The lines are filled with Glysantin.

I replaced my system with an electrical system from the E30 and some custom parts as the system has do be working if it ist installed. It's a major fault at the german TÜV (MOT check).

[Brucey]

that is interesting. I think in theory the same may apply to the UK MOT, i.e. if the system is there it ought to work, but in practice this kind of rule is rarely enforced. I think this is sensible in this case because the hydraulic system was originally an option (not standard equipment) and when it has failed, the lights are normally still manually adjustable, more or less as if it had manual adjustment from the start.

I have often thought that many electrical systems for headlight adjustment are lacking in this respect; should the system fail there is often no manual adjustment possible.

BTW do you happen to know which grade of Glysantin is appropriate?

Also, if anyone has good photos of the cracks that may be show-stoppers, I'm sure they would be of interest to others.

cheers

[stevejordan100]

Thanks everyone for all the information. I am going to try and fit the left hand version, by routing as suggested . I will lay it all out with appropriate size tubing (ie same as comes supplied with the original left hand part---my dealer will get the information for me) too see if it fits via a new route also see where I can to push the controlling switch through the bulk head . If I am successful I will document and put it up on this forum.

[miike87]

that is interesting. I think in theory the same may apply to the UK MOT, i.e. if the system is there it ought to work, but in practice this kind of rule is rarely enforced. I think this is sensible in this case because the hydraulic system was originally an option (not standard equipment) and when it has failed, the lights are normally still manually adjustable, more or less as if it had manual adjustment from the start.

I have often thought that many electrical systems for headlight adjustment are lacking in this respect; should the system fail there is often no manual adjustment possible.

No the lights are always manually adjustable. There is a screa on the backside of the motors.

BTW do you happen to know which grade of Glysantin is appropriate?

Is's just normal Glysantin just as in the cooling system. But I got no proof for this.

Also, if anyone has good photos of the cracks that may be show-stoppers, I'm sure they would be of interest to others.

2016-03-22 21.10.37.jpg (1.98 MiB) Viewed 13696 times

It should be clearly visible on the socket and the bleeding point.

[monoi]

I fitted the left hand version, as it is the only available from BMW, in my right hand car.

The hose go out from the scuttle in front of the driver, and there is plenty of tubing to reach both headlights. Make sure you have automotive sealant before you do as the exit point needs resealing.

The only issue is that the knob turns the wrong way, ie the numbers are under instead of over the knob.

If you want some pics, let me know. I might just put some up tonight anyway.

[Brucey]

^ nice work!

I suspected it would be possible but hadn't seen it done; I'm sure some pics of your installation would be useful for all the RHD folk with this issue.

cheers

[stevejordan100]

If you could post pictures that would help, where did you come through the bulk head?

[monoi]

Here are a few pics:







What I got wrong in my previous post is that the numbers are above, so the 0 position is now the 3 position and the knob moves the wrong way. I guess one just needs to get a used left hand version of that part.

[nick88highline]

I have just done this on my car. The LHD aim system will fit, but as described above the pipes are routed slightly differently. Normally on LHD and RHD systems, both pipes would be routed down the left side of the engine bay and then one pipe goes across the nose section of the car in front of the radiator. In my install the pipes are routed down both sides of the engine bay. It was quite hard as the pipes are slightly too long.
As for the control, it seems like the LHD part is slightly different in that it has more travel and so the inscription panel must be changed for one from an E30 (on the right) as can be seen below:



Not sure why because the inscription panel part number is the same for both LHD and RHD cars. I guess this means the overall calibration is slightly off, but does it matter that much?
I covered the pipes in silicone tape, slit tube and cool tube to protect them from damage as I don't want to do this project again anytime soon.

It's interesting to note that many other cars used this same system including such high end marques as Porsche and Skoda. Some of the Porsche guys have found a way of re-filling the system: http://rennlist.com/forums/928/779368-h ... rhaul.html but it looks hard.

I'll post some more pictures of the ridiculous lenghts I went to with this project.

[rod635]

Hi, I recently bought my first E24 that has been in storage for 14 years. After getting it mobile again I was wondering about those white brittle pipes thatare broken in the engine bay, I thought they were for the headlight squirters but after removing the panel below the steering wheel to replace speakers, they had actually rotted, I realised they are for the headlight beam adjusters. Before I put everything back together can I use headlight washer tubes to replace these and any ideas how to get the system operating again. Ps rhd shadowline model.

[monoi]

As indicated earlier in the thread, I cannot see how those things can be professionally repaired, let alone DIY. They were still available from BMW a couple of years ago. They are for left hand drive cars but they fit.