british seagull info request

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no onecares

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Dec 16, 2007, 8:49:29 AM12/16/07
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I know some of you cruisers are using a british seagull engine for
your dingy.
I just purchased one, in good running condition, but has no paperwork.
Where can I download manuals, info, etc?

I know I can buy them, but I am sure there are some groups like with
the A4 that share them and talk up a storm!

thanks

Joe

Bruce in Bangkok

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Dec 16, 2007, 8:01:43 PM12/16/07
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Google "seagull". There are several sites providing advice and parts.

Bruce-in-Bangkok
(Note:remove underscores
from address for reply)

Ian Malcolm

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Dec 16, 2007, 7:35:01 PM12/16/07
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The company that ended up with the British Seagull spares inventory and
rights and continues to support the engines has the copyright to the
user and service manuals. (Selva ended up with the rights to produce
Seagull branded engines but have nothing to do with supporting the
original engines.)

The consensus on the various forums is that although the OEM parts
supplier is rather expensive, ripping off their copyright is a *BAD*
*THING* as no-one wants them to decide supporting Seagulls is uneconomic
and dispose of the remaining inventory. The original works docs were in
'dead tree' format so there were no conveniant files for employees or
dealers to leak.

Generally anyone trying to trade in ripped off scanned manuals gets
banned from the forums so DONT unless you dont want to have access to
one of the friendliest and most helpfull user communities you will ever
meet.

The Owners Handbook is *real* simple and any of the forums or supplier
sites will give you a brief list of the essential do's and dont's, so
you can easily do without it. The Service Manual is actually a
collection of service bullitins and Seagull used to send the same
bullitin individually if one ordered a particular service kit. Most
suppliers would still be happy to send a copy of the carburettor diagram
if you were ordering carb parts etc. though you might have to ask. The
Owners Spares Book is the exploded diagrams and parts list but the
forums will help you get part numbers given a description and the better
suppliers will send you the right parts as long as you give them the
engine number so one can manage without that as well. The Retail Price
List is just good for giving you sticker shock, e.g. eight years ago,
the GBX10035 BEVEL PINION (12 Teeth) was £47.17 and it hasn't got any
cheaper. I shudder to think what that would be now in dollars and you'd
need to replace it as a set with the Crown Gear as well. Be very
carefull to use the correct spec gearbox oil and check it often!

The best seagull forums are at http://www.saving-old-seagulls.co.uk/
Goto the 'Guest Pages'. If you have any servicing to do or operational
questions - just ask over there.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL:
'Stingo' Albacore #1554 - 15' Early 60's, Uffa Fox designed,
All varnished hot moulded wooden racing dinghy.

Edgar

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Dec 17, 2007, 9:28:31 AM12/17/07
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"Ian Malcolm" <valid.address...@invalid.invalid> wrote in message
news:fk4oec$9fa$1...@aioe.org...
> was Ł47.17 and it hasn't got any cheaper. I shudder to think what that
> would be now in dollars and you'd need to replace it as a set with the
> Crown Gear as well. Be very carefull to use the correct spec gearbox oil
> and check it often!
>
> The best seagull forums are at http://www.saving-old-seagulls.co.uk/
> Goto the 'Guest Pages'. If you have any servicing to do or operational
> questions - just ask over there.

That is all good stuff but you hardly need the instruction book for these
simple motors. I have had long experience with them and my Century Plus is
50 years old and still good for another 50 as they are very much
over-engineered by modern standards and will accept a lot of abuse and still
run.
The older Seagulls, 40 and 100 series at least, have one great advantage
over modern engines in that the water pump impeller is not made of rubber so
you can clamp them to a bench and run them up dry for a minute or so ashore
and then you know they will start without hassle when you put them on your
boat.
Here is all you really need to know:-
-Use basic 2-stroke oil, not the high tech stuff they use in modern
chainsaws etc. Seagull recommend a 10:1 mix but if you use this on an engine
that is well run in you will have trouble with plug oiling and lose even
more of the oil into the environment. I run mine on 15:1 and it is OK.
-Oil in the gearbox must be SAE 140 or thicker, as long as it will still be
pourable (i.e. not a grease). The gearbox has no oil seal and the thick oil
leaks only very slowly through the clearances. The instruction book says "a
certain amount of water in the box doesn't matter" and you will find that
the oil becomes a yellowish emulsion of oil and water. I have never seen a
Seagull where this did not happen and the loadings are so low they run
happily on it. I have never known one that needed new gears from wear .so
the cost of new gears is not a problem.
-Spark plugs may be a problem as 18mm ones are hard to find. I have a little
hoard of old ones as they do have the advantage that they can be dismantled
for thorough cleaning so last a very long time. The recommended plug is
Lodge C1 (H1 for hard service) or Champion 8com. There may be some modern
equivalents made for vintage engines but I have no information on this.
Recommended gap .012/.015"
-You need to carry a plug spanner, a screwdriver and,if you have the old
Villiers carburetter, a precision spanner ('King Dick' type) for unscrewing
the jet if it gets blocked. With these three tools and a spare plug you can
be sure of getting the motor going again_in the boat_ in the unlikely event
that it stops.
HTH


Ian Malcolm

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Dec 17, 2007, 8:04:37 PM12/17/07
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Edgar wrote:

> "Ian Malcolm" wrote:
>>The best seagull forums are at http://www.saving-old-seagulls.co.uk/
>>Goto the 'Guest Pages'. If you have any servicing to do or operational
>>questions - just ask over there.
>
>
> That is all good stuff but you hardly need the instruction book for these
> simple motors. I have had long experience with them and my Century Plus is
> 50 years old and still good for another 50 as they are very much
> over-engineered by modern standards and will accept a lot of abuse and still
> run.
> The older Seagulls, 40 and 100 series at least, have one great advantage
> over modern engines in that the water pump impeller is not made of rubber so
> you can clamp them to a bench and run them up dry for a minute or so ashore
> and then you know they will start without hassle when you put them on your
> boat.
Non contact centrifugal impeller. If you are tank tesing they wont pump
water unless you take the prop off. DONT idle slower than it will pump
*some* water at.

> Here is all you really need to know:-
> -Use basic 2-stroke oil, not the high tech stuff they use in modern
> chainsaws etc.

ANY TCW I II OR III 2 stroke oil even if its fancy stuff or if you have
nothing better SAE30 single grade non-synthetic non-detergent engine
oil. As Edgar said, NOT the oil for air cooled engines.


> Seagull recommend a 10:1 mix but if you use this on an engine
> that is well run in you will have trouble with plug oiling and lose even
> more of the oil into the environment.

Problem is the other way round, early seagulls and very worn ones *NEED*
10:1 to seel the crankcase bearings and get enough compression.


> I run mine on 15:1 and it is OK.

*most* seagulls can be converted/may allready have been converted to
25:1 for less smoke but possibly more rust ;-(. *most* engines can be
converted to 16:1 just by carb adjustments. Anyrthing that says 25:1 on
the tank, use 25:1. All others, expect to start off with 10:1 then with
the assistance of the forums, get it down to a reasonable mix. WARNING
altering the oil ratio affects the mixture and can cause the engine to
run lean. DONT run a seagull lean with a heavy load


> -Oil in the gearbox must be SAE 140 or thicker, as long as it will still be
> pourable (i.e. not a grease). The gearbox has no oil seal and the thick oil
> leaks only very slowly through the clearances.

There is an oil 'seal' on the prop shaft thats just a rubber washer in a
recess in the gearbox casting behind the brass bush pinned to the
propshaft behind the prop. Its mostly just to keep grit out. If its too
badly chewed up, the engine pisses oil. If its replaced with a flat
face V seal running against the face of the rear shaft bearing the
gearbox will hold oil to the correct level with very little
contamination for several seasons. Later seagulls have proper oil seals
and use streight SAE90. If the seals are damaged substitute SAE140.
Dont use multigrade. The SAE140 oil is most usually used in old tractors.


> The instruction book says "a
> certain amount of water in the box doesn't matter" and you will find that
> the oil becomes a yellowish emulsion of oil and water. I have never seen a
> Seagull where this did not happen and the loadings are so low they run
> happily on it. I have never known one that needed new gears from wear .so
> the cost of new gears is not a problem.

Geears only die due to corrosion, If too much oil has escaped, the
emulsion breaks down and the gears get exposed to raw seawater. They
then rapidly rust and the housing also gets badly corroded. Also if the
engine is stored for a long time, you can have problems (easily avoided
by running the engine for 1 minute every month or two to keep the oil
and water mixed) or if some idiot has filled the box with grease. All
it takes is unscrew the oil plug a couple times a season with the prop
downwards and then lift the engine towards vertical to check the oil is
up to the minimum level. Put the oil plug back before more than a trace
escapes. The gearbox fill level is level with the bottom side of the
filler hole with the engine vertical. Slight overfilling doesnt hurt
but Segull warn aganst overfilling.

> -Spark plugs may be a problem as 18mm ones are hard to find. I have a little
> hoard of old ones as they do have the advantage that they can be dismantled
> for thorough cleaning so last a very long time. The recommended plug is
> Lodge C1 (H1 for hard service) or Champion 8com. There may be some modern
> equivalents made for vintage engines but I have no information on this.

the Champion 8COM is long discontinued and are rare and valuable if in
good condition. Champion D16 is the (more) modern equivalent or NGK A6


> Recommended gap .012/.015"
The book says .020" and if the ignition system is in good contition and
the flywheel magnets are good, there should be no need to reduce this.
Difficult to start engines *may* respond well to reducing the gap to the
range stated by Edgar

> -You need to carry a plug spanner, a screwdriver and,if you have the old
> Villiers carburetter, a precision spanner ('King Dick' type) for unscrewing
> the jet if it gets blocked. With these three tools and a spare plug you can
> be sure of getting the motor going again_in the boat_ in the unlikely event
> that it stops.

Add a small adjustable spanner to tighten loose nuts, and a spare drive
spring and split pin and you can get it going as long as nothing
critical has dropped off and sunk as happened to me 18 months ago :-( I
ended up with a Red Bull can instead of a float chamber (the float
floated so I recovered that) to get me back to my mooring!. A small can
of WD40 and some paper towels in a ziplok bag are also worth carrying.

Happy Seagulling.

Gordon

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Dec 17, 2007, 11:43:08 PM12/17/07
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.
> Non contact centrifugal impeller. If you are tank tesing they wont pump
> water unless you take the prop off.

I don't understand this. Can you explain a little more?
Thanks
Gordon

Ian Malcolm

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Dec 18, 2007, 3:08:58 AM12/18/07
to
Gordon wrote:
> ..
Yeah, sure, no problem.

A normal raw water pump uses a vaned rubber impeller in an assymetric
chamber. The base of the chamber and the cover plate need to be close
fitting and the pump works by compressing the vanes moving back fromn
the outlet to the inlet nearly flat so that far more water (in the gap
between the vanes) is moved from inlet to outlet as the rotor turns than
can get back on the side of the chamber with the bump. The pump has
rubber rubbing on metal at a couple of thousand RPM. The only thing that
stops it destroying itself instantly is the plentiful supply of cold
clean water its pumping which cools and lubricates it. Remove the
water or add a little sand and it will chew itself to bits faster than
you can yell 'STOP'. This is a positive displacement pump, i.e. its
output is proportional to its speed (as long as it isnt overloaded) and
it pumps from a very low speed.

A seagull does things rather differently. The water pump chamber is
cylindrical and cincentric on the drive shaft. In the chamber is a hard
four vaned rotor running on the shaft with a top plate around the
shaft of about 2/3 the rotor diameter. Water enters around the shaft in
the middle of the rotor at the bottom and is spun to the outside of the
pump chamber where it exits upwards via the gap between the rotor top
plate and the chamber wall. The closest the rotor ever comes to any
stationary part is about 1/16" so as far as the pump is concerned it can
run dry all day with no damage though the powerhead will get pretty
unhappy after a minute or two with no cooling! It also isnt much
bothered by a bit of sand or sediment as long as the liquid its pumping
is fairly runny, its happy.

Where the trouble starts is it cant lift the water enough to get it to
the powerhead at low revs and also it cant pump effectively if it gets a
big air bubble in the chamber so the top of the chamber *must* be
totally below the water line even when moveing. If you are testing the
engine in a small tank, it stirs in too many bubbles so the pump doesnt
work worth a damm and the engine may overheat. Take the prop off, no
stirring, no bubbles and you can test it all day with no problems. You
want to test the engine under load, moor alongside with your stern
pointed towards open water please, rig a strong bow spring to keep you
there and test the engine on the boat. One can keeep that up for as
long as people near by are willing to put up with the noise.

Richard Casady

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Dec 18, 2007, 10:41:14 AM12/18/07
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On Mon, 17 Dec 2007 15:28:31 +0100, "Edgar" <ejc...@REMOVEonline.no>
wrote:

>you will have trouble with plug oiling

A bandaid is platinum point plugs. Those fine wires can run very hot,
and cool fast enough to avoid preignition, and they don't burn up. The
auto makers recomment you change them every 100k miles.

Casady

Richard Casady

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Dec 18, 2007, 8:44:43 PM12/18/07
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On Mon, 17 Dec 2007 08:01:43 +0700, Bruce in Bangkok
<b_pai...@gmail.com> wrote:

>>I know I can buy them, but I am sure there are some groups like with
>>the A4 that share them and talk up a storm!

Depends on how you feel about stealing. And it would be pretty easy to
get caught.

Casady

Edgar

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Dec 19, 2007, 2:20:11 AM12/19/07
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"Richard Casady" <richar...@earthlink.net> wrote in message
news:4771e916...@news.east.earthlink.net...

But can you get them for a motor that requires 18mm plugs?


Douglas Eagleson

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Dec 19, 2007, 7:52:22 AM12/19/07
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I rebuilt an old segull once. My big mistake was neglecting the
ignition system. And the coil was bad making it real hard to start.
I luckly found a guy way back with a spare. If you were a coil
winding type of shop you just might get one rebuilt. It was super easy
to start with the new coil.

It also had a leaky carburater. Gas would leak out the little hole on
the side. Implying a bad float or float needle valve. The float was
perfect, the valve was not. I was real upset at the cost of a new
carburator so i got mad and got a hammer and peened the needle into
the seat with a tap of a small hammer. Believe it of not, the floated
needle then worked perfectly with no overfloaws. A light hammer job:)
I could not believe it. It saved half the cost of a new outboard.
Parts are hell.

The little impeller housing for the water pump was all corroaded due
to heavy salt water uasge. Dismantling thelower unit revealed a
perfect hard plastic impeller that never makes contact with the
housing sides by design. It is a durable plastic likely to not be
ever an issue unless age makes it crack. Although salt water can clog
all water passages eventually after a season of hard usage.

The leaky gear box shaft seal is an issue. Adding oil every day
stinks. You just have to live with the issue and add or check the oil
every other day after heavy usage. I neglected the issue and burned
out the upper pinion gear. Parts were findable twenty years ago. Now a
days a new set, just might mean a new outboard would be a better
choice.

It should be considered a style of outboarding I believe. Seagulling
arround and all. A lightweight four horse power johnson is a good
alternative.

Richard Casady

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Dec 19, 2007, 9:28:44 AM12/19/07
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On Wed, 19 Dec 2007 08:20:11 +0100, "Edgar" <ejc...@REMOVEonline.no>
wrote:

Good question. Wouldn't be that hard to bore out the hole a bit, to
the closest available larger size. Certainly plenty of metal around
the existing hole. I mean it isnt' a hemi with the biggest possible
valves. Two strokes are mostly flatheads.

Casady

Richard Casady

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Dec 19, 2007, 9:32:44 AM12/19/07
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On Wed, 19 Dec 2007 04:52:22 -0800 (PST), Douglas Eagleson
<eagleso...@yahoo.com> wrote:

>It should be considered a style of outboarding I believe. Seagulling
>arround and all. A lightweight four horse power johnson is a good
>alternative.

I understand parts are ridiculously expensive on those too.

Casady

Brian Whatcott

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Dec 19, 2007, 9:06:38 PM12/19/07
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On Wed, 19 Dec 2007 14:28:44 GMT, richar...@earthlink.net (Richard
Casady) wrote:

...
>>> A bandaid is platinum point plugs....


>>
>>But can you get them for a motor that requires 18mm plugs?
>
>Good question. Wouldn't be that hard to bore out the hole a bit, to

>the closest available larger size...
>
>Casady

Uh? 14 mm plugs are the usual platinum offering, I believe.
An adaptor might do the job.

Brian W

Richard Casady

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Dec 20, 2007, 12:21:19 AM12/20/07
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On Thu, 20 Dec 2007 02:06:38 GMT, Brian Whatcott
<bet...@sbcglobal.net> wrote:

>Uh? 14 mm plugs are the usual platinum offering, I believe.
>An adaptor might do the job.

I didn't know that. I do know they are great, are pretty much immune
to fouling and last at least 100 000 miles, which i just as well,to
since it takes two hours on my current ride. My 75 Volvo had a lot
under the hood, but plugs took five minutes. It always had room for
the tools and a hand, and you never had to take stuff off to get at
other stuff. The good old days were when you could work on the motor.
Stuff like brakes haven't changed and the shade tree mechanics can
still work on them.

Casady

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