MGB Register Forum

Can any help decipher this engine number ?. It is a 1970 Glacier White GT for sale here in Australia but does not conform to the normal id ranges ( 18V) for this model.

Eng # 18U780H3782 Chassis # GHD5220403G

Many thanks

Garry

Hi Garry,
I have asked Thomas is Oz to see if he can assist with your query.

Someone in the UK might have the answer also.

If I hear anything I will let you know.

StaySafe

Paul

According to my workshop manual, the 18V779 & 780 engines were the predecessors of the 847. The former were to ECE 15 emissions regulations as were the 847, and are pre 1976 so they're likely to be fitted to early rubber bumper cars.
They have a 25D4 distributor whereas the 847 had a 45D4.
Hope this helps.

Hi Garry,
Just received a Reply from OZ.

Hi Paul

All MGB GT cars in Australia were fully imported, so the engine numbers should very closely follow those of the UK cars. Even the Australian built MGB roadsters used fully imported engines, so those engine numbers too will roughly follow the UK cars, but with more variation due to engines being fitted to cars being built somewhat haphazardly.
As you probably also know, the early three bearing engines were 18G, (18 = 1800cc, G = MG), then 18 GA (3 bearing, positive crank case ventilation), 18GB (five bearing), 18GD (first Mk II) then the 18V series. "H" indicates high compression ratio (vs L) and H should follow "U". U I seem to recall indicates a floor (vs a column mounted) gear change. So the given engine number seems incorrect; no "G" for MG, U not followed by H, and as the poster states, by 1970 they were fitting the 18V engines.

So the best I can conclude is that either the engine is not original, or the engine number is not original. Remember the UK engines had the engine number stamped on a plate riveted to the engine. Easy in those circumstances to change the engine numbers. By nation-wide legislation, all Australian engines had to have the engine number physically stamped into the block, which in the MGs was on the cast block surface where the plate was riveted onto for the Abingdon assembled cars.

Regards Tom

Mike Barclay might have different info.

Could the U be a V?

StaySafe

Paul

Hi Paul
Looked through all my books but can’t find an 18U engine listed for an MGB. As you mention, is it possible the V has been mistaken for a U? As Vic states the 18V780 was fitted to early rubber bumper cars and built to ECE 15 emissions regulation with HIF carbs, AAU needles and 25D Distributor. This was just before the big change to the notorious 45D 41610 distributor and weak ACD needles needed to pass the emission tests.
A picture of the engine plate might help.
Mike Barclay

Thanks for the replies ... I think it may have been a rebuilt block and renumbered. Attached is a photo. The owner does not

Clearly an 18V engine!

18 = 1.8 litres
V = "vertical". i.e in line cylinders.

I can't imagine that designation being changed, unless "U" means " down under"

Ian F