RF91 Control box renovation question

[Greg Hoeft]

I am rebuilding a RF91 L34 #37031A control box for use on my early TC with a C45YVG C24 generator and wish to confirm the specified number of the split series compensation winding turns on the regulator bobbin. There are now four full compensation turns and three auxiliary load turns in this control box and they look to be original. From my internet research I believe the RF 95/2 #37057 should have the same configuration of turns as the RF91 box but not the TD version RF95/3 #37065. I have not been able to find any Lucas manufacturing specifications for the various vehicle application model numbers. Any ideas where I might find out the control box details? Is #37031A the correct RF91 model number for an early TC? Any help is appreciated. For the last 19 years I have had a RF95/3 #37065H control box in my TC with three compensation turns and two load turns and it never crossed my mind that there was a difference in the various model numbers until now. According to Lucas documentation the load turns must match the generator specifications.
Greg Hoeft TC1415

[Duncan M]

Greg-
The later TC RF95/2 #37057 box has different windings numbers from the RF91 you reference. The RF95/2 #37057 is also different than the TD box you describe, designed for a different dynamo. RF95/2 #37057 produced in 8/49 and fitted to TC9866 (production date 10/49) has 2 and 4 windings.

[Greg Hoeft]

Thanks Duncan
Your report about the 95/2 having 3 and 4 turns may explain why another RF91 #37031 used in a TC had one turn unwound from the load windings. Lucas may have changed the design for the later TCs.
Greg