MatraSport Forum

Each model => Espace => Topic started by: Martin Tyas on August 27, 2010, 11:55:08 pm

Title: Xenon headlamp levelling
Post by: Martin Tyas on August 27, 2010, 11:55:08 pm
Whilst I was fitting new rear discs and GreenStuff pads last weekend I spotted the drop link between the rear axle headlamp levelling sensing potentiometer and the torsion bar was detached. Upon closer examination I found that the lower ball that should have been attached to the torsion bar had sheared off.

I had hoped that this was a separate part but true to form it only comes complete with the potentiometer at the ridiculous price of 83 plus VAT, according to the current Dialogys.

So I set about finding suitable ball & sockets to fabricate a new link. There were plenty of suppliers but the only ones I could find were Business to Business suppliers with minimum order quantities of 50 or more. I even tried such as Karting parts suppliers but couldn't get exactly what I wanted but would have maybe been able to utilise a rod end instead of ball & socket if I couldn't find exactly what I wanted.
Then I came across a German company that manufactures all types of self lubricating plastic bearings, bushes, rod ends, plastic chains and all sorts of other industrial plastic products for actuators and controls. They had a UK operation but are also B2B suppliers. However their on-line order system didn't have a minimum order quantity only a requirement for it to be a business and not an individual to order. So I ordered through the company. Although the price was higher (4.24 each for quantities of less than 20 and going down to 1.25 for over 50) I could live with that compared to over 96 incl. VAT for the full potentiometer.
But I still needed a rod between the 2 ball & sockets. So, rather than buying rod and then having to run a 5mm threading die down each end I went to an on-line model fixings shop that supplies all sorts of small fixings for model builders. They had short lengths of fully threaded rod in steel, stainless steel and nylon. For how little expense it was (0.70) I thought I would order some nylon rod as well as stainless steel but when I got it I wasn't convinced that it was going to be rigid enough so I used the stainless steel instead. Even with the next day courier cost of 6.00 for the ball & sockets I still fixed the problem for less than 16. Pictures attached for anyone interested.


Title: Re: Xenon headlamp levelling
Post by: Anders Dinsen on August 28, 2010, 12:11:40 am
Nice work, Martin!

Title: Re: Xenon headlamp levelling
Post by: yellowt5r on October 30, 2010, 10:59:30 am
Hi Martin,

i went to get some tires fitted on the rear and when i got back i notice my "droplink" was broken. not sure if it was them where they jacked it up or just old age. do you have any of these as i notice you have bought a number of them.


Title: Re: Xenon headlamp levelling
Post by: Martin Tyas on October 30, 2010, 12:05:44 pm
I will look out what I have left over this weekend and get back to you.

In use they don't actually move that much because they are fitted to the torsion bar and not the rear axle beam. So, I think what happens is that the ball joints are kept free from rust to the normal extent of their movement but then when the car is jacked up and the axle beam and torsion bar go through full travel the ball joints are required to move much further. With the rust on them and also due to being weakened by the rusting process the combination is enough for it to make them give way at the neck of the ball ~ the narrowest part. That's my theory anyway because it also happened to mine after I'd had it jacked up but to replace the brake pads in my case.


Title: Re: Xenon headlamp levelling
Post by: Martin Tyas on October 31, 2010, 09:21:47 am
OK, I had a couple of spare ball & sockets and enough stainless steel rod left so I've made up another to the exact length required ~ I still had the old broken link kicking about in my garage and so could use that as a pattern.

The ball has both a hex socket in the head and also hexagon flats but the flats are very narrow so use the hex socket to hold the ball from rotating whilst you tighten the nyloc nuts I've included.
Fit the balls to the torsion bar and potentiometer arm first and then put the bearing cups over the ball heads and then push fit the ball & sockets together until you hear the retainers click and the cups  are all the way home. If you assemble the bearing cups into the sockets first then you won't get the ball into them.
You will see what I mean from the pictures I've included with this post.

PM me your address details and I'll put it in the post.


Title: Re: Xenon headlamp levelling
Post by: yellowt5r on October 31, 2010, 11:09:18 am
PMed you Martin, thanks alot for the help.