In recent weeks I have been researching information about the Stag ignition distributor, and conductiong some tests to evaluate performance. The work covers all aspects from points, to electronic igntition to Electronic Advance Distributors, and I will be publishing some reports in due course which I hope some will find interesting and maybe useful.
The vacuum advance aspect has been bothering me for some time as I had a feeling something was odd, so today I inspected all the distributors in my possession to see what types are fitted. I have three dissys type 41336 (early engines) and three 41525 types (late engines). These are fitted with a mix of two different vacuum advance units marked 5-11-6, and 6-20-7.
These codes denote the vacuum (in Hg) at which they start and finish working (first two numbers) and the maximum advance in degrees.
From the WSM it appears that the 6-20-7 belongs to the early 41336 dissy, and the 5-11-6 belongs to the later 41525 type.
On checking which was fitted I found that out of six distributors, only three had the correct vacuum unit, the other three (50%) were wrong; that is a very high percentage. You may want to check your own distributors to see what is fitted. The numbers are usually stamped on the nose tip of the vacuum unit; you may need a lamp and to clean up with some wire wool in order to see them.
The vacuum advance aspect has been bothering me for some time as I had a feeling something was odd, so today I inspected all the distributors in my possession to see what types are fitted. I have three dissys type 41336 (early engines) and three 41525 types (late engines). These are fitted with a mix of two different vacuum advance units marked 5-11-6, and 6-20-7.
These codes denote the vacuum (in Hg) at which they start and finish working (first two numbers) and the maximum advance in degrees.
From the WSM it appears that the 6-20-7 belongs to the early 41336 dissy, and the 5-11-6 belongs to the later 41525 type.
On checking which was fitted I found that out of six distributors, only three had the correct vacuum unit, the other three (50%) were wrong; that is a very high percentage. You may want to check your own distributors to see what is fitted. The numbers are usually stamped on the nose tip of the vacuum unit; you may need a lamp and to clean up with some wire wool in order to see them.
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