Not information that you will need on a daily basis, but it might come in
handy sometime along the line.
Gold Seal Engines for MGB
Thanks to The MG Owners' Club http://www.mgownersclub.co.uk/ 'Gold Seal' engines are factory replacement complete engines painted gold instead of the usual maroon or black. They are re-manufactured engines, i.e. ones that have been exchanged under warranty or for some other reason. They will have been completely dismantled and every component tested and measured to make sure they meet spec, and any that don't are replaced. As such it is probably better than an original engine, which are simply assembled from parts out of a box with the quality and 'correctness' of those parts assumed. There were also Silver Seal short block engines, i.e. without heads or ancillaries. Gold Seal engines have special prefixes which can be decoded to the original prefixes, see below:
Gold Seal Equivalents:
OEM Prefix Compression Gearbox Gold Seal Prefix
18G High Manual 48G 279; later 48G 343
18G Low Manual 48G 280
18GA High Manual 48G 343
18GA Low Manual 48G 344
18GB High Manual 48G 392; later 48G528 48G 739
18GB Low Manual 48G 393
18GD/GG Low Manual 48G 527; later 48G 736
18GD/GG High Manual 48G 528; later 48G 702 48G 755
18GD/GG Low Auto 48G 529; later 48G 736
18GD/GG High Auto 48G 530; later 48G 755
18GF/GH High Manual 48G 539; later 48G 704
18GJ/GK High Manual 48G 704
18V581/582/583 High Manual/Auto 48G 733
18V779/780 High Manual 48G 733
18V581/582/583 Low Manual/Auto 48G 736
18V584/585 Low Manual 48G 737
18V672/673 Low Manual 48G 737
18V836/837 Low Manual BHM 1074
18V797/798 Low Manual BHM 1105
18V801/802 Low Manual BHM 1105
18V846/847 High Manual BHM 1111
Note: BHM 1105 thought to apply also to later North American 18V883/884 18V890/891 and 18V892/893 engines.