The 'E' Type Forum

Dear,

I need to find out which o rings I need to seal the axle shafts of my '72 S3. I have ordered o rings P/N 12473 according to the jag parts list. However, they are several mm smaller than the old ones and don’t fit in (fill) the groove in the diff housing.





I have read that there are different configuration of the output shaft bearings. Some have the o ring groove in the bearing, while in my diff, the groove is in the diff housing.



Is my differential not original for a '72 S3? the casting number on the housing is:



I have measured the OD of the bearing which is 72 mm (2,835"). The groove is approx. 4.5 mm wide and 3 mm deep (0,177"x0,118"), but that is only an estimation since I cannot measure exactly inside the housing.

Does anyone know what diff I have got and which o ring I need?

Thanks and best regards, Manfred

Hi Manfred.....I have what i believe is the same type of Diff in my S2 2+2....it definatly has the same type of output shaft and bearing arrangement...this diff is commomly refered to as the "3rd type".....it was quite a while ago that i had mine apart and thought the O ring was actually a square shape seal....the part i used was as you quoted 12473.....im sure what i got was square....possibly the suppliers dont have the correct part.....i aslo looked up in the S3 service manual and it does refer to the Square section seal... have a look here note 5 and you can see the seal in the diagram....Steve PS..contact Alan Slawson he is one of the best diff builders in the UK....im sure he can help http://www.ajsengineering.com/