Saving Old Seagulls

Hi All,
I have just purchased this BMB Outboard, along with a couple of others. This motor looks to be all there, except for a water pipe and a wire spring thing, that attaches beside the spark plug.
Can anybody advise what year and model this may be. It seems to be pre 1948 , going by pictures I have seen.
Thanks.
PS, not sure why the pics are laying down. maybe they are tired, like their owner lol

the serial number, stamped near the tiller mount is
OS / G / 6573.
not sure if this is a date code, or the RPM limit.LOL

Nice engines the BMB. What you have there is what I think of the middle model, introduced aprox mid 1930s. The lightwin came first around 1930 ish or even the very late 1920s. The model you have used a comon powerhead shared between outboard, inboard (Wirt gearbox drive) and an outboard/inboard called a midi.

These do show up on ebay here a few times per year. Hard to find parts!

You have the outboard version obviously, but the cylinders seem quite different. See attached pics. Can you take some better quality pics showing more detail?

The swordfish was introduced in the early post war period approx 1946. You can see the different tank etc. Beyond this we don't have a huge amount of hard facts.

I have two of the early lightwin models, which are lighter and easier to carry

The lightwin looks like the attached photos of one of mine. It has an air cooled exhaust silencer, which is a lot simpler!

The weakness of the BMB models are the cylinder castings, which often rot out, as they don't drain very well.

Some intruiging adverts attached. The 1946 advert suggests the Swordfish was available then, but the middy is still advertised also.

I do like the BMB engines

Some more adverts and an article.

Hi Oyster 49,
Thanks very much for the info, and pics. I have taken a few more, showing better details of the barrels.
Cheers,
Again, not sure why the pics are on their sides?
Is it because I live down under? LOL

Also interested in the carby. Is this correct for this model.? It seems odd, with the little throttle lever.
Cheers.

The carb is correct, but the throttle lever arrangement looks like it has come from a Middy model. You can fit the correct throttle body top which is the same as a seagull 102 and also fit a seagull throttle lever and cable. IT should fit. Correct throttle lever is the bronze amal lever as fitted to Seagull SD engines. See my pics posted above.

Whats intriguing is the cylinders and exhaust collector. I've not seen anything like that before. Fascinating

I believe the outboard that Notav8 has is actually a Britannia Ensign from the late 30's. It should have a cast aluminium cover which protects the spark plugs and carb - hence the different style of cylinders. The carb and throttle are correct as both the throttle and choke lever would protrude through the cover.
The original Britannia Light Twin was introduced in late 1932 with a chromed lower unit with a two bladed vacuum propeller. 1934 this was changed to a three bladed propeller and water scoop. 1946 saw the engine have a steamlined fuel tank and an aluminium lower unit, with a wooden grab handle being added a couple years later. But the blue tank motor that Oyster posted is different, I have found a 1947 advert which referred to this as a 'Services Model' - but when it was introduced or whether this saw war time service I have no idea!
Hope this is of use.

Thanks Oyster and Ferrier.
I appreciate your help and info.
Im pleased that you have come up with a model name. I will have to try to find some info, on the Britannia Ensign. I have not heard of this model before. i suspect that the cast Alloy cover, may be difficult to source.
Would anybody have a picture of what the cover looks like, or a picture of the outboard.
Very exciting stuff. !!
Cheers

Ensign and service model adverts

WOW!!!
Thanks very much Ferrier 120.
At least I know what to look for. LOL
I am assuming that the cover will be almost impossible to find, but I am always optimistic .
Are you also a Ferrier Collector?, as I have a 120 also.
Cheers

Lots of great information, pics and adverts posted in this thread.

We never stop learning!

Regards,
S

I personally like the BMB engines. They are interesting to work on, and fairly rare, particularly the pre swordfish engines. Also fairly cheap too. great addition to any collection A few spares about if you ask about here.