Hello Maarten,Maestro wrote:My 4 Cooper-Jarrets have 3 colors of bogey/dolly: painted dark blue, painted silver and unpainted bare metal.
Is there any relation between the C-J versions and the dolly used?
Or is the type of dolly used random on all 4 'basic' versions of the C-J?
Maarten
No, the dolly use was not random at the time the M9 was made from 1962 to 1967. There is a specific order.
Your silver painted dolly is interesting as I have not heard of a silver "painted" dolly (coupler or bogey ) though , and we would love to see photos if possible if you are able to post them. If so could you place it alongside the unpainted version, perhaps viewed from top and bottom. I do have unpainted shiny and unpainted dull finish examples.
Some references refer to the dolly as silver but it should be termed unpainted so that it not confused with silver trailer, silver doors or even silver trim on the M9.
The dolly comes in blue or unpainted and can have 3 wheel types fitted.
The blue dolly can be fitted with the dual detailed one piece wheels that have text on the outside face and inside face
The blue dolly can also have dual wheels fitted that are smooth on inside face.
The size of both of these dual recessed types differ in width and diameter.
The blue dolly can also be fitted with the black plastic standard regular wheel (BPW)
The unpainted dolly was only ever factory fitted with BPW regular wheel type.
Note the BPW can also come in two different sizes.
As it is now almost 50 years since the M9 was discontinued and boxes, inserts and components get swapped about, so many M9 are often seen with a mix of tractor - trailer - dolly which may differ from what was intended at factory.
From a purist point of view the rear wheels of the tractor unit should be same as trailer and dolly.
A summary about trailers and dolly in terms of wheels on the M9 you mention are:
M9 with detail recessed wheels, silver trailers blue doors - has blue dolly.
M9 with detail recessed wheels no text inner face, silver trailer blue doors has blue dolly.
M9 with BPW grey trailers can have blue dolly.
M9 with BPW grey gloss trailers can also have factory unpainted dolly, as the grey gloss painted trailer was the first to have unpainted dolly.
M9 with BPW silver trailers silver doors (orange or yellow decals) unpainted dolly with BPW.
Here is an image to show the wheel detail in the order they came out of the factory.
Bert