Seized 40 Featherweight...

[Element]

Hi,

I know very little about Seagull engines... let alone how to overhaul one; but needs must – I do a lot of boat fishing in the summer on a local loch and have been graciously given an outboard engine. However, there's a snag...

I think it is a 40 Featherweight EF; here's a picture:





It was used on an Avon dinghy at sea and one night in a storm, it flipped over and the top section of the outboard was submerged (probably for several hours). It was then put in a shed and left there for several years (5+ ?).
It is as you'll expect, seized. I have taken the top cover off :



I figured I'd have to get at the coil and points and clean them up, to do that I understand you need to turn the flywheel back or forward until the piston is fully back... and one pair of hands holds the flywheel while another knocks the spindle from above with a hammer...However the flywheel will only rotate back and forth over maybe an inch and a half and no more – on looking through the plug hole – I don't see any movement of the piston at all... So I can't guarantee the piston is in the right position to remove the flywheel...

So, my first question is how do I free up the piston? Do I for instance undo the apparent bolts that are at the front and back – one being close to the words 'do not remove' which is on the back of the cylinder block... Or is there another way to resolve the situation?



I tried squirting a copious quantity of WD40 in and leaving it but to no good...

The prop only turns a bit against its spring...

Any advice will be greatly appreciated!

Cheers

Tony.

[Charles uk]

There are no points on this featherweigh model, the chances are that the failure to rotate problem, lies in the gearbox.
Remove the front cap from the lower unit so that you can inspect the contents & perhaps post a pic if the problem lies there.

[Element]

Ok thanks, I'll do that - and report back.

Cheers

[Waggles]

Another trick for a stuck piston ( if that is what it is ) is hot oil. Carefully heat some normal engine oil over a gas ring / camping stove outside and pour in the plug hole. ( You want it very hot but don't go crazy and try to get it boiling or catching fire! ) As the cylinder and piston should expand at different rates you should be able to free it up. Attempt to rotate flywheel etc while its all still hot.

[Element]

Great idea - I'll look at that too this weekend and see what happens...

many thanks.

[Horsley-Anarak]

If it were me (only my opinion and only based on what I have tried myself), I would take off anything that is easy to get off first.

Tank, carb, tiller, flywheel and back plate,leg and exhaust etc.

Most of these things will need looking at and cleaning out.

The steel tank may well have rust in it, unscrew the fuel tap and have a look at the filter on the end of the fuel tap (the last EF I bought the filter was blocked solid). I have found that if there is rust in the tank, block off the outlet hole with a piece of stick, pour in 1/2 pint thinners in to tank with 2 hands full of pea shingle (just nick it off drive if you dont have any). Put the cap on and shake it, this will dislodge all of the loose rust and give you almost a sand blasted finish to the inside of the tank. then wash it out and dry it.

If you take the leg off this will let you see if the gearbox is locked solid, if the prop turns when not connected to the power head, then the problem is the piston.

The lower end of the crank shaft will be square cross section, you will be able to get a spanner on this to see if the piston is rusted solid. Do not swing on it too much or you will snap it of or round it.

If you half fill the gap above the piston with a a thin oil or better still a volatile penetrating solvent like WD40, then put back the plug.
Now if you warm up the cylinder the penetrating oil (you hope) will be forced down past the piston and rings, also thermal shock will help.
Putting it in the oven works well for heating it up 200c (having removed all things that are made of plastic and can melt), if that is not possible you will be suprised how hot you can get it with a hair dryer.

The carb will need taking apart if it has been full of water, I find that a smal ultrasonic tank works very well gets all of the gunk out, if not small brush and detergent works (dry well).

If after all of this the piston is still solid (at your own risk, pistons are not strong) find a piece of wooden dowel that will fit through the plug hole, then gently give the piston a few gentle taps with a small hammer, I have found that this can work.

If none of this works then you will have to take the head off, to give you better access to the piston. if the bore is red rust and pitted buy a new power head.

Look forward to you getting it going, good luck!

H-A

[Charles uk]

This is a seagull with a CDI ignition, heat more than 60 degrees C will probably cook it

[Horsley-Anarak]

Yes sorry Charles missed that little bit, have done edit.(I would only heat it up with flywheel and base plate off).

H-A

[Element]

Many thanks... I'm going to be busy. I'll post back the results as I discover them...

[Element]

Life kind of threw a box of spanners at me last year and I had to put the Seagull in the garage corner and leave it until I had more time and opportunity to have another go at fixing it... Now that time has appeared (over 14 months later!) and I have moved further along with the project. However I still am somewhat stuck and have some questions - really appreciate the help here!
Having taken the flywheel off we found the inner assembly to look in not too bad condition. We've undone bolts all over trying to get as deep into the heart of the engine to figure out where it is seized. We can now see two horizontal screws that appear to hold the piston in position but they're in such a position that you can only get 1/2 the screwdriver on their heads so they don't appear to be possible to remove at the moment. We find that with a pair of tight fitting molegrips on the 'upper shaft' we can get a tiny bit of movement but not enough to see the piston visibly move although we suspect it is seized - we don't actually know this - as it could be the gearbox that has the seizure around the driveshaft instead - or worse still - both!
Last year Waggles and H-A suggested a hot oil treatment for the piston... I will attempt that this weekend.

Can I ask how the gearbox can actually be removed? Immediately above it there is a bolt + clamp around the driveshaft tube, I have removed that, but short of walloping it with a wooden drift and a big hammer - how do you actually remove the gearbox? Inside we have removed the 'gearshaft' and we can see the drive point which seems rusty and grubby. The driveshaft tube appears to be held on at the upper end by two bolts; one on the outer side and one in between the driveshaft tube and the exhaust tube... Can anyone tell me how we can undo the inner bolt!? Tried all our spanners and sockets but because of the design we can't fit anything on to undo this inner bolt! Maybe we don't actually need to if it is only seized at the piston, that might be the jam and if we get that moving then maybe we won't need to worry about the gearbox and it'll turn freely... If so we'll just reassemble everything and move to trying to start it. Am I right to think it is EP90 gear oil that should be used in the gearbox? I read somewhere that these are supposed to run on a mixture of oil and water emulsified in the gearbox; if we fill the gearbox with oil - will this gradually come out and the result become a mix of the oil & water?

I'm determined to get it going before the summer arrives; winter seems to still have its grip up here with snow and hail showers at this time of year...

Many thanks for all advice

Tony.

[Hugz]

John has a comprehensive set:

http://www.saving-old-seagulls.co.uk/bu ... spares.htm

Only two sets left!

[skyetoyman]

Far easier to remove the gearbox than to start at the top. Just two screws in the top of the transom plate but you need a good screwdriver , a good spray of WD40 and the whole bottom end will slide off.

[O'Dubhain82]

I had a similar problem with my forty plus. I think the previous owner
ran it on a fuel mix made up for a "modern" outboard, with predictable
results. The piston was seized. Very seized. Someone on this forum came up
with a great solution - take an old champion 8 spark plug and disassemble.
Then thread a grease nipple onto a washer and weld the washer onto the
bottom half of the spark plug. With this you can now use a grease pump
to force the piston down as far as the exhaust port. That may be enough
to free it. Assuming you can even "sort of" weld (like me) this is fairly
easy.
Also, to address the problem of removing the gear box, it is possible
to weld a metric nut onto the center screw on the water pump
housing. This makes it easy to remove.
http://farm4.static.flickr.com/3344/460 ... 19dd_m.jpg

[Jeff, Ohio USA]

If I'm following your post correctly at this point you have the flywheel and ignition plate off the head. Once a motor is at this point I've had good luck in the past soaking the head in a 50/50 mixture of used motor oil and kerosene or fuel oil.