MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Dist. number question

My MGA 1600 is running what I believe to be the original distributor. The numbers stamped on the side are: 40510H BN 238 360.
I found a very nice used distributor that I could not pass up. I would like to rebuild it, then switch them so the car would not be down. The numbers on the one I picked up are: 358 BN238 40510A DM2.
My question is what do the numbers mean and would I have any problems using the new one? Anything I should be watching for?
Thanks, Jim.
Jim Jensen

Jim. The DM2 on the cast portion of the distributor body housing the vacuum advance is the basic design of distributor. The 40510 is the basic specification number for your distributor. The letter suffix indicates some form of minor change in the distributor which does not affect the specification. The 360 on your original distributor means it was produced in the third week of 1960 while the 358 of the second distributor indicates third week of 1958. Unusual to find both distributors made in the same week, two years a part. My DM2 distributor was made two weeks later, being stamped 560.

I am not sure what the BN238 signifies. My DM2 also has this marking. Later model distributors simply have the specfication number stamped in the boss with the three digit week/year code below that. As a general asside, Lucas seems to have produced most of the MG distributors I have examined in the early part of the calendar year. The highest date code I have on a distributor immediately to hand is 1267 for the 12th week of 1967. I have seen codes as late as the 47 week point on alternators and starters. The lower date codes on most MG distributors have caused some to believe that the first one or two digits were the month of production. Not true as I have verified with my own observation and through British sources who had contacts at Lucas back during the days when MGs were being produced.

Hope this helps. Les
Les Bengtson

Continuing to explore trivia...I dimly recall reading somewhere that Lucas switched from a month/year code to a week/year code some time in the late '60s or early '70s. The earliest year I've ever seen with a month/week number greater than 12 is 1973. And I've never seen a month/week number greater than 12 with a year earlier than 1966. Admittedly my sample space isn't huge, though.
Mark Lambert

Check the bottom of this page under Distributors:

http://www.wolseley.asn.au/flyingw/fw1/tuning.html
Gene Gillam

This thread was discussed between 26/04/2005 and 27/04/2005

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.