CLAYTON DEWANDRE ” MOT-A-VAC ” Sir,
Early this year I bought a VW caravan (Mr. White’s Caravette) and what a lovable, lumbering vehicle it is. Even a Mini can’t dazzle you through that high rear window—but you have to be careful not to trip over them and remember to pull out when passing them; oh yes, I have passed seven Minis this year (is this a record ?). I carve notches in the dash, to keep count!
Soon after I had it I found the brake pedal pressure too high for comfort and about twice that on my Fiat 600 Multipla, which made changing cars rather dangerous. In March, this year, therefore, I ordered and fitted a Clayton Dewandre ” Mot-a-Vac ” servo to the VW. With it came a tailor-made kit of plumbing but no detailed fitting instructions. After one or two dummy runs I found that you were supposed to salvage the existing rear, 3-way, union to fit at the front, when everything went fine. The mixture of metric and pipe threads in the, C-D kit has to be seen to be believed; the fitting took about three hours, all told. I fitted the unit inside the rear blanket locker, rather than in the engine compartment, since it was higher and easier to bleed (and I rather like the wistful noise it makes), and ran the vaccum pipe horizontally to the adaptor on the inlet manifold. All went well for about i,000 miles, when I was driving a party of American friends down a steep pass in North Wales and the servo-assistance went! Being an innate optimist I was delighted to find that the brakes were still there—even if the old, high, pedal pressure was back, and I found this experience reassuring. What was most distressing, however, was my impending departure in two days’ time for three weeks in the Alps! How did one get ” queer ” spares in a hurry ? This was Sunday and next morning
I rang Clayton’s London office, who referred me to their Mot-aVac Manager at Pinner who was just leaving for Coventry; he listened to my story and said his wife would make the required arrangements.
I had stripped down the unit and found the main, power, rubber diaphragm split; I suggested that a new one of these would do me very well if I could get it that day and offered to meet any train from the works (at Lincoln). However, I was promised that something would be delivered to me, at my office, by lunch-time. Nothing arrived up to 2 p.m., so I went home to start packing for the morning ferry. The things that happened afterwards were art object lesson to other manufacturers. At 4 p.m. one of C-D’s engineers rang me at home, having got my number from my office, found where I lived and drove over. By 6 p.m. he had fitted a complete new unit, added a right-angle adaptor to the vacuum tapping on the inlet manifold and rerouted the pipe with an initial, vertical run of about a foot. It seems that the pulsation, at low revs., in the VW manifold had managed to pump petrol vapour into the servo which had attacked the rubber. Their engineer, Mr. G. A. Johnson, was most concerned that this could happen and did all possible to make sure we got away for our holiday in time. He refused all payment since the unit was still under guarantee, and after a cup of tea left for his home, 30 miles away, at 7 p.m. He fitted a plastic vacuum pipe in place of the original rubber one so that staining by migration of petrol could be seen—if it continued—and gave me an additional spare power diaphragm just in case we ran into trouble in Austria! This was all six months and 6,000 miles ago and the unit is now working perfectly, slight yellow staining of the pipe shows that petrol vapour is reaching the first two inches of the vertical pipe and is over four feet away from the unit itself. If any of your readers are thinking of fitting this excellent brake servo to a VW then I hope this tip will be of help. The local VW people, Royal Berks Motors, in Reading, continue to be amazed at the way the caravan stands on its nose now. I would also like to think that a firm like Clayton Dewandre, to whom I am just a retail customer, know how much this sort of service is appreciated and what an object lesson it is to some other manufacturers. (I won’t bore you with my experiences on tyres—you have heard it all before!)
Cold Ash. W. H. Bossotvs. * *