Repairing a headlamp vacuum unit

Not a very good week-end. :frowning: On top of my suspension problem, I realised one of the vacuum unit headlamp actuator is broken. Looks very nice from the outside but obviously the membrane is torn as the system is no longer tight. I wonder if it is not possible to repair the membrane. The problem is that the two unit halves are sealed together. Does one of you have a good idea to repair it and avoid to have to spend around 80 GBP to get a new one?
Olivier.

Hiya
I would god for carefully splitting it in two with either a hacksaw or cutting disk in a dremmel or equivalent, to reseal just use GRP not a problem, the whole of the bottom of one of mine is like that!

No idea about the membrane, as not sure how it is secured in, you might be better prising the edge up all the way around at the joint in case it is trapped between the two halves, then if you can get it out go find your local pneumatics place and see if they can match it with something similar.

Andy

Are you sure it is the diaphragm (membrane) that is leaking or damaged? the outer casing (vacuum side) could be leaking usually due to rust.
In my experience the diaphragm does not usually give problems.
I have in the past fibre-glassed the outer shell and sealed it, if you want to save money and are not too concerned about its looks give it a go.

Once upon a time in the land of Thatcher and Miner and Printer strikes I repaired my pods. I ground away the turned lip, around the edge and seperated the two halves. Laid out the components and checked out what was knackered. The top was rusty, but that wasn’t too important because the vacuum is in the bottom half. The rod was rusted to a thin thing from the planet Thin, no prob… used a brass welding/brazing rod to the same pattern and bolted it through the rubber membrane. The bottom half of the sphere had various pin holes that were no problem to braze over.

As to how the rubber was held in place while the seal was remade I can’t remember. I do remember that money was short (still is!) and the repair was fairly straightforward, works, done by two students, and is still in the car.

After the repair, (which wasn’t really a pretty sight) everything was covered in Waxoyl which has probably saved it from deteriating further.

Hope this helps a bit, even if it only gives you the confidence to slice them open!

Will post a pic asap.

Alternatively go for an electric conversion. IIRC the unit from the Mazda works. Search this forum for the details.

A long time ago I cut a segment out of the top half, poured in some Copydex (latex gue) and sloshed it around the diaphragm, hoping that the extra layer would serve as a new diaphragm which it did.

Hi all,
I had that similar problem which I sorted by raiding a toyota celica at a local breakers yard. I converted my car to electric operation, I know its not now original but it works every time with none of the headlamp creep which was always a pain.
Regards Simon
+2 130s

Oliver,

 A few months ago I posted a extensive run down on my pod repair adventure. It involved putting a tube sealant for mountain bike inner tubes into the diaphragm on both sides (this stuff is called Slime here in the States), also sealing any rust holes with good silicone sealant, and clamping all hose connections. The key point though was installing a new non return valve just downline from the old one. This new valve should have a "cracking pressure" of 3 PSI not to let vacuum move the opposite way on hills or under full throttle. 
 Good Luck,

Rob