Saving Old Seagulls

Hi
First a BIG thanks to John (SoS) for patiently listening on the phone to my tales of woe while also trying to direct his house hold re-cycling needs . I have a LS 40 plus which was bought complete 2 years ago on eBay which had been stored in a shed for many years ,the usual story . Over time I have been getting it back into shape , I have a Freeman 24 so knew that Sheridan had taken on Seagull so bought many parts from them . This Easter should have been the test run hence the frustrated call to John . No matter what I did the little LS would not run . I did discover during several carb strip downs that a 25:1 needle had been fitted so the initial 10:1 fuel mix was increased to 15:1 to get a bit more petrol into the equation . I put a new plug on with a healthy spark , points and plug set to 20thou . I removed the prop to reduce drag in the test tank , later dispensed with . I appear to have good compression (thumb over plug hole test) . I have plenty of black oil omitting from the exhaust tube , but still the little blitter will not run . I do get the occasional single firing but no more . I have tried all approachs of language at the little LS and also have an open booking at A&E to have my right arm muscles massaged though I am now having dis-believing looks as to nature of the injury's !
I am not very familiar with 2stokes my belief is that they are so straight forward they should give little trouble , , I hear the chuckles . On my last attempts in the sunlight I did notice puffs of vapour coming out of the carb air inlet as the engine was spun . It has been suggested that I may be drawing air in from the top crank bearing so I have drizzeled gear oil through the flywheel onto it and it has remained . Everything seems to be drawing me towards removing the head and cylinder (square type) but I am very nervous of doing this as on the LS the head bolts are threaded directly into the crankcase . Any ideas from the forum please , I am at a total loss .
On a brighter note a BIG HELLO to you all , I am a new member , one of the good things I have found of owning old "problems" is the discovery of so much help and interest that is out there and I hope that the knowlege I have already gleened may in itself be able to steer others one day to solve their illusive niggles .

You have a spark, so magneto is working. Good start.
Is the plug wet after trying to start? If so you are getting fuel ok. If not clean the petrol tank, fuel line, and carb carefully. When ticking the carb the float bowl should fill and trickle out of the hole in the float bowl.
Is the flywheel backplate in the right position, and is the flywheel fitted correctly with the key located beween flywheel and crank?

If you have a spark at the right time and fuel in something like the right mixture it should run! The points should be opening just before the piston is at top dead centre.

Sounds like timing is out. The 40's have a different base plate position than the rest. Picture?

My SD was just like that when the crankshaft key failed and the flywheel slipped. Check to see when the points are opening relative to the movement of the piston.

Hi
Good feedback , thanks , trouble is all the boxes are ticked . I wondered myself about the timing position but according to the Seagull manual it's in the right place . As always when you don't know it's history you just have to go with a blank canvas and I suppose that's really part of the fun , so , next weekend its back to the drawing board ,will keep posted

When I bought the LS I new nothing about the following that I was to discover , just memories of my childhood when my Dad had Seagulls on his boats and it just seemed the obvious choice to relive that wonderful time and the challenge is certainly very enjoyable if not a little frustrating at times . I'm now 64 so I've got a lot of catching up to do , bring it on !

On the subject of fuel tap corks the little LS's had really shrunk to less dia than the tap shaft , on reading Johns advice I did the boiling water exercise and after 2 soakings in boiling water and then leaving immersed in water for a week or so the cork swelled so much that getting it to go into the barrel of the tap was an effort , but the seal is purfect . £15 on eBay I don't think so , thanks John .

Maybe it's a carburetor problem and it's over fueling/ flooding. I wouldn't of thought you should be getting black oil coming out unless it was flooding.
I had all the same symptoms when one of my engines had a dodgy carb fitted. The carburettor was off something else and the needle valve on the float wasn't up to the job of sealing when moving around on water. Fitted the right model carb, took a while to sort jetting but it now runs like a gem.

If your needle valve is dicky and you were trying to get it going with the dodgy tap cork it's possible that even when you thought the tap was off to try and reduce fuel it wasn't actually closing and causing constant flooding.

I have a newly rebuilt Forty Plus which started almost immediately and ran well on day 1.
The following day I just couldnt start it. After an hour of investigation (Spark, fuel, flywheel, compression) Eventually, I re checked the carb and found the throttle was only opening half way. A quick cable adjustment and it started with the throttle lever fully open. I am guessing more air was required?

Thanks everyone , lots of ideas to checkout , will have to be at the weekend now as the LS is not at mine . The piston I do know is the right way up , will check timing again although base plate and lead to mag are in the right place for a 40 . I may source a 10:1 needle as the LS 40's were not intended to run on 25:1 if all else fails . As I said before without knowing its past it really is trial and error . Ironically when I first stripped the carb I noticed the needle screw was turned in and not level with the top , at that stage I didn't know it was a 25:1 needle , however thankfully all the bearings are good ,maybe it never ran after the needle was changed which was why it was sent to the shed to be forgotten about for many many years . Happy Seagulling to all

Is the magneto plate tight onto the crankcase? A slight wobble affects the points gap and also earth continuity. Not sure why you are getting black oil from the exhaust tube with very limited firing. 15 to 1 oil mix may be too rich when running 25 to 1 needle. I would be squirting some straight petrol into the carby to see what happens. They run on WD40 too....

Dicky my seagull has rejoined my flock of four seagulls ,if you need to borrow a working carb,i have a,forty and a forty feather weight running now ,p .m me I am in Audley.

Regards Dave

Cheers Dave

Thanks for the offer . Interested in your mention of omission through the carb as I have the similar happening , so if all other areas checkout ok , the barrels coming off . It would make sense that the rings are stuck in the grooves as I 'm sure it was stored for some conciderable time . When I opened up the gearbox it was solid with emulsified oil , it was just like sandstone and had to be carved out . Outwardly though it wasn't too bad just very dusty .