SD Restoration

[Cheshire Cat 4]

Hi,
Can anybody help me with the transom bracket on my SD eng No SD.10621.L4.(1942/45)
This was bought without a transom bracket 2yrs ago in a sorry state. I now have it up and running and would like to fit
the correct bracket .
I have some spares and wonder if by chance one of them would be the correct one (see attachment)
I also have 3 carburettor cowls with the same problem (?) A.B.or C.
The tiller handle has a threaded end could this be for an extension it looks original but have not seen one before
The smaller engine is AD 2594 (1947/48) this could also have the wrong transom bracket

[charlesp]

The bracket currently on the SD would be a better bet on the AD, the bent thumbscrews are 'of an age'.

None of the brackets you have there would have been used on the SD as issued. Much discussion has occurred regarding SD brackets, I believe that the majority would have been issued without a bracket but with a simple brass/bronze spigot at 90 degrees to the drive shaft tube, allowing possible attachment of various styles of bracket that seemed to suit different styles of craft. I also believe that a few may have been issued with what we tend to refer to as the 'skeletal' bronze bracket. Some motors, without a doubt, would have been intended during those years for what I'll call an ordinary small boat, and that bronze bracket would be the obvious choice.

There are a few brackets around associated with military motors that ended up over the water - I refer to them as 'Dutch' brackets. They are solid and strong and many SD motors seem to have them, but there is no indication that they came from British Seagull. However, here's one for comparison purposes:

An SD has a short water jacket, it has a 'coolie hat' magneto, and a steel tank. There are theories that later in the series - at the tail end of the 10,000 or so production run, they may have been fitted with brass tanks and the post war 'flat' magnetos. I can see little sense in this and tend to disbelieve those theories. Many have lost their magnetos due to later replacements - the entire magneto is interchangeable with later models - and many steel tanks have rusted out to be replaced with brass alternatives.

The SD had alloy tank strap lugs, and the straps themselves were Jubilee clips. They had a bayonet fitting tank, the cap had a breather. Some were fitted with an aluminium magneto cover, some with a copper one. Pay no attention to anyone trying to convince you that a copper covered magneto means the engine was in some way involved with dealing with magnetic mines.

The drive shaft tube was usually zinc dipped; again there are survivors with chromed tubes. I have one myself. But I don't think they're original, there would be no sense in it.

I haven't encountered a threaded end on a tiller arm before.

[skyetoyman]

I would have said c on the intake -- however the brass intake supplied by John may be more fitting and does look good. 100% not b as sd's didn't have a choke.
Hand over intake for one pull then a little throttle and once stated partially cover by hand until running well.

[charlesp]

I missed off the bit about the intake! Apologies. The correct one for an SD is a trumpet type - look carefully at my upper photo.

Sorry about that. Well spotted skyetoyman...

[Keith.P]

I was wondering why the top picture, left transom didn't look right, the tilt bar should be in the bottom holes and the clamps screw mounts should go in the middle hole, that should make it look better.
Also looks like a lot later flywheel on it.

[Oyster 49]

Nice pair of engines Inlet should either be item A or the brass trumpet for the SD. I don't think there is any real proof as to what was fitted when, but I suspect the "Item A" inlet came along later in the production run, with the trumpet being earlier in the production run.

Regarding later magnetos, there are several engines on the forum with later flat top magnetos, that are very late in the SD series of numbers, that may or may not have had that magneto from new. So it could be possible that very late engines had flat top magnetos. Who knows

Petrol tank mounting brackets - I have a late model SDP with brass plate tank brackets, and 2 earlier SDs with cast alloy brackets. The later SD I have sold recently had brackets made from brass plate. So again I suspect the cast alloy brackets were a feature of earlier engines, and the brackets made from brass plate came later.

However this is only suspicion, and we may never be able to find out for sure.

Incidently for any 102 restorers, I have recently found some tank straps (Jubilee clips) on ebay in either stainless or zinc plated. 90-120mm. Item number 290686383642. I have obtained a couple and they seem spot on.

Those tiller wing nuts are very hard to find in brass!

[Keith.P]

Regarding later magnetos, there are several engines on the forum with later flat top magnetos, that are very late in the SD series of numbers, that may or may not have had that magneto from new. So it could be possible that very late engines had flat top magnetos. Who knows

I'm no expert and they are nice motors, but that left mag looks more Wipac than villiers?

[charlesp]

Just because you have sold one with a brass tank and plated lugs doesn't make it authentic!

Sixty year old motors tend to accumulate later components.

My considered view is that SDs had coolie hat magnetos, steel tanks, aluminium tank supports and trumpet air intakes.

You are, of course, at liberty to believe whatever may suit you.

[Charles uk]

I think we can say for certain that the flat top flywheel was never fitted to an SD when it left the factory, the quest goes on to establish when Villers started producing it, we have 2 members investigating from different directions, we wait with baited breath.

Logic would dictate that when the Ministry of Supply ordered 10,000 SDs in 1942 for Seagull to assemble, they would have ordered 10,000 + spares from Villiers, at that point Villiers would start producing 10,000 + spares, the were not taking these off the shelf from stock they were making them.

We have seen no evidence that anything other that intake trumpets were ever used.

There is no mention of flat top ignitions, cast air intake shrouds, pressed brass tank supports in any of the wartime Seagull parts lists.

The jubliee clips used on early fuel tanks only had the thread grooves on a very short part of the band unlike modern ones that are almost completely threaded.

A working SD with a few later parts is still a thing of beauty.

The other Charles has a considerable amount of the paperwork on these motors far more than I have seen, let's wait for his imput.

[Oyster 49]

It's nothing to do with if I've just sold an engine or not, it's about reviewing all the engines I have seen, that then leads me to suggests certain theories. Thats all.

And I did not even mention tanks, only tank mounts and inlets.

Nobody knows what is right and wrong, so all any of us are likely to come up with are discussions/suggestions as to what might have been fitted when.

[Jan]

I've seen too many (later) SD's with the 'Seagull' air intake to believe all the SD's where fitted with the trumpets.

As long we don't have wartime pics (with time stamp) we are not sure of the air intakes, magnetos, brackets etc. used on (later) SD's.

Jan

[Charles uk]

The ones you see Jan are somewhat different, they were supplied to the Dutch Military post war, from the packing dates in English on the spares boxes that could have been sometime in the very early 1950s, at that time with no coolie hat ignitions in production at villiers & no air intake trumpets being manufactured at Seagull the spares kits would have to contain parts that were in current production, though I admit Prufrex in West Germany were making the M1030 x16 coils right into the 1960s.

Adrian after you have surveyed 30 or 40 SDs for the data base you have to keep, when you get the SD register up & running, you will start to develop an overall picture that should tell you that out of the 10% of SDs that are fitted with flat top flywheels their engine numbers are spread right across the production run & that the spread of JM numbers roughly cover 10,000 engine numbers, & that there isn't room in the numbers to add maybe an extra 500 flat top ignitions.
It takes a lot of dots joined together to make a picture, whilst working on the Marston register I have probably looked at over 90% of the known examples, a majority of the Marston owners also have several SDs in their collections & with the ones I've owned, I probably seen more than 50.

One thing we have found is that the roughest examples often give us the best information, they were dumped when they stopped working & nobody has messed with them trying to get them going.