Series 2 brake servo piston lubrication.

The revised instruction leaflet for Duunlop disc brakes which came with the 'Manual Of Instructions' for my TD 21 Series 2 says :- "The piston in the servo should be lubricated every 10,000 mls. by sliding back the short length of hose so that it clears the junction of the pipes at the side of the unit , and injecting approximately 25cc of Shell Donax A.1.oil into the elbow of the pipe connected to the end cover of the servo." I have never heard of lubricating a servo in this way and can find no reference to it on the AP Lockheed web site. Could anyone please tell me if they have ever lubricated their servo in this way and if so what equivelent to Donax A.1.oil was used. I have exposed the sevo unit under the wing and indeed located the short rubber hose mentioned but the unit does not look like it has ever been disturbed. I would be very grateful for any information on this. Colin 0208 852 7803 (London) Posted by Colsim 03/07/2012 15:07:09

Colin I have what I believe is a 1964 Lockheed Disc Brake System Service Manual and am willing to scan the section on the vacuum servo if this helps. The section has diagrammes of the unit in section view. It may be of some use to you. Other sections cover, adjustments, clutch operation, fault finding and routine attention.  If interested please advise an e-mail address. Posted by RichardWallach 12/09/2012 09:00:30

My servo was sticking, the brakes were not going off. I found it impossible to slide the rubber hose back as suggested but I did lubricate it with Shell Donax TX as recommended by Shell. It wqs then OK. Shell Donax TX is an automatic transmission fluid Posted by dcsaunders 08/10/2012 22:32:10

When I overhauled the brakes on my TE, I did a bit of research to find an equivalent, and came up with a straight 20 grade, which if memeory serves me right was intended for use in motorcycle forks, unfortunately the brand name escapes me. Posted by greg124 21/11/2012 15:25:43