Lagonda Rapiers

3 minute(s) of a 484 minute read

Meanwhile being 2.45 Friday afternoon here in Australia, I have just telephoned the Brake Repair people, They could tell me that while my brake shoes etc are finished I will not be able to collect them until Monday.

11-16-2018

Unfortunately the local "Brake People" do not know about Preselector gearbox bands These have been sent at great expense to England to one of the few firms prepared to tackle relining the gearbox bands. These have to be riveted as they have to live and work in a bath of oil. The recommended oil for preselector gear boxes is simple SAE 30 engine oil (without any additives). Because firstly these gearboxes were incredibly rugged with standing all sorts of abuses and secondly because most 1930s cars were simply not used between 1939 and 1946 ......

Peter Meyer the expert on ENV Trans in Germany has explained that he uses a pair of "Vice Grip" pliers to compress and hold the springs when assembling the "centralisers". He also uses a slightly diferent sequence in assemlinig these which should help. Only time will tell.
 
The bands themselves while they look simple, are in themselves quite complex. Todays photograph shows the friction surfaces of these two bands. This at first glance may sound misleading but for each gear the "Band" has two strips of friction material. after riveting they have to be ground internally to size and machined to aid the bedding-in process. This photograph shows one "band" finished and the other prior to machining. The metal part of the band is extremely complex. To date I have been unable to find a drawing that adequately shows its construction. Not only does the band have to contract sufficiently to stop the selected gear's drum from rotating it also has to self-adjust to compensate for wear. This is self-adjustment take place every time a gear is selected.  
It really is quite simple. I will let you look at the second photograph taken through the top of a gearbox and attempt to work out what is going on for your selves. For me to do it for you would take more than a page of typing to explain the action fully. *
Just don't let anyone tell you that Major Wilson was anything other than a brilliant engineer.
 
Bj.
* Having just looked at the relevant pages in the original Lagonda "Rapier Owners Handbook" I have found that there are almost 20 pages plus another eight pages of drawings devoted to the gear box. A bit too much to compress into one or two pages.
Please don't go away, it is just that we may have to do this one thing at a time. There are some good photographs in there that I can share with you, that is if you really want to continue down this path?