Diagnosis on grumpy Seagull

[Reptile Smile]

Hi all,

Your advice would be gratefully received.

I've bought a 'new' engine, and have been out with it twice.

The first time it started straight away in the mooring. Good stream of cooling water. Went out, sails up, came back. On the way back in I started it - it was fine (though sounded a bit funny). I put it into gear, and dropped the sails. The engine cut out, and wouldn't restart. I swore. We put the sails back up. In the end, I noticed somehow (god knows how) the fuel tap was off. I pulled it out, it reluctantly started, we motored back in.

I have no idea whether the fuel tap got knocked as part of the frantic rush to restart it, or whether it was part of the original problem. I certainly think part of the issue (possibly unrelated) was it was flooded.

The next weekend (this weekend), I started it in the mooring. It was fine. Good stream of cooling water. We motored out. On the way back in, I started the engine. It started (though was grumpy), though sounded a bit funny. I thought the problem might be low fuel - put more in , pre-mixed with Wilko's finest (3 quid a bottle) which was different to the last brand - 10 to 1 (the original owner said it was ten to one, but slightly less (don't know whether he meant less petrol or less oil and will get back in touch with him to check).

I put it into gear, and it cut out. It then simply won't restart. Sometimes it sounds like it's firing, but it's not nearly 'coughing' into life.

I then resign my self to sailing in. Sails up. Wind drops right at the mouth of the mooring. I swear. Tide is carrying me past. I give the engine one more go, and it starts. In neutral it's fine. Putting it into gear makes it grumpy. I have to give it full beans in gear, but it takes us in and home.

1) Why is the problem on the way back in? Might it be related to 'dragging' it in the water behind the boat (I didn't bother to lift the pivoting transom bracket up because the tilt bracket is knackered, so I just dragged it behind (and both times had had a fresh wind and therefore plenty of drag just before trying to start it on the way back in). Might water have got forced somewhere? Might this be related to why it maybe drains when left between trips and therefore starts fine in the mooring but not when restarting it when sailing?

2) Wilko's two stroke oil. Discuss. [8m]

3) Flooding. What do I need to know and how do I avoid it? How long between running a Seagull will necessitate choke? (An hour? Two? A day?) Should I always start it on full beans, or half way, or just keep patience while I find out what it's happy with? Should I always 'tickle' the carb? Or not if it was only an hour since it was last started?

4) Any other diagnoses that strike anyone? I was bang on the money of 10 to 1 as far as I know - how tolerant might it have been to errors in this?

Many thanks in advance for your collective thoughts...

 

[Lakesailor]

I bet all your questions can be answered here http://www.saving-old-seagulls.co.uk/faq/faq.htm Scroll down a bit to "How do I start my British Seagull?"

Is it 10;1? If it has the 25:1 needle or the needle has been lowered in the slide it wil run on 20:1 or 25:1. Depends on the model and the carb. See website.

Usually needs full choke but also the throttle nearly wide open. Sounds daft, but that seems to work. (I think that creates a strong suction effect on the jet).

Theoretically 2 stroke oil should be marine as they run cooler than garden equipment. But it shouldn't make any difference in the short term, and Seagulls use different bearings to most motors.

Tranona used to work for them so he can probably give you the complete chapter and verse.

 

[Searush]

Some ideas that may or may not be relevant.

1/ Could it have been modified for 25;1 mix?

2/ if the fuel tap is loose, so that it can slip in & out easily on its own - & possibly leaks a little, then remove it & boil the cor for a few minutes. It should absorb water & expand so that it works properly.

3/ go to the SOS site and spend a few hour of happy browsing for more detailed info. It is a wonderful site for those of us who love the classic old motors.

 

[ECLIPSE]

I'd be using proper oil specific to marine outboards; my understanding is that the operating conditions of a seagull engine, and say a 2str motorcycle/ generator/ chainsaw are different, and warrant special oil. I have read that this is to do with operating temperatures.
If in doubt, I'd try another plug,check the gap, and check the HT cap and lead over.
10:1 is right for older and/or unmodified engines.
On my seagulls, cold starting procedure was:
cord round flywheel
petrol on, tickle carb till it dribbles
choke on
throttle about a quarter on (this varies from engine to engine) and give it a tug or two.
Ive always regarded seagulls as amazingly dependable (if quirky) bits of engineering, one century of mine could be started when hot by spinning the flywheel by hand BUT, you need everything in your favour to get the best out of them. I never had any problem with over-flooding an engine using the tickler, other than the pollution factor!
Enjoy! John

 

[yellowspinnaker]

Yes, go to the SOS site, where the FAQ bit is most helpful. Visit the SOS forum, too, there are lots of experienced Seagull users there: http://www.saving-old-seagulls.co.uk/phpbb3/

Quote the engine number, you'll find a set of Letters and numerals on the lower part of the alloy crankcase, where it meets the drive shaft casing. That'll tell the good folk on there which model you have, out of lots of possibilities. It'll give an indication of fuel mix ratios, too, unless it's been modified.

Talk over all your issues there, you'll find the people most helpful, there's a heap of expertise there, much of it from ex Seagull people.

 

[TrueBlue]

I have / had the same problems with my 'gull. My solution doesn't make sense, but it works.

Whe it won't start - it's always for the same reason:_

The last two years I have found that the float chamber collects an amount of green gunge. Over a period of time the (original) fuel pipe also collects the same.
Clear both of these and the engine runs prefic'

Otherwise engine starts easily, gets me to the boat, but not return. Changed the oil to different brand - no change. Ask manufacturers' oil expert -"haven't seen that before".

• 
  Fuel tap always turned of at end of trip
• Always run fuel out rather than stopping engine.
• Doesn't happen whe engine is store over winter (I always leave fuel in the tank to stop the cork seal drying out)
• Doesn't make any difference if mix is old or fresh.

 

[VicS]

I agree with the suggestions to visit the SOS website and also the associated forum.
All the info on the website about converting from 10:1 to 25:1 if that is suitable for your engine.

The mixture proportions are not critical... you dont need science laboratory measuring accuracy, but dont just guess.

Yes you should be using a TCW3 outboard engine oil but these old seagulls were produced long before there was such a thing.

I do now run mine using TCW3 oil but I used to use garden machinery oil and before that a straight SAE grade 30 oil ... did not half smoke at 10:1 but it ran OK.

 

[Reptile Smile]

Thanks all for ongoing suggestions.

Ratio unmodified is 10:1 (haven't yet extracted carb nedle as don't have the 'radiator key', but will do as soon as I can), variant is Silver Century Long Shaft with Clutch (WSC). I hadn't posted it here, but can do if anyone's interested. Will have a go on the SOS boards as well. The first thing I did was have a look on their site, but had forgotten their boards.

TrueBlue, are you saying that in cleaning the float chamber and fuel pipe, it stopped the 'start cold/not start warm' problem, or that this persisted even when you'd done it?

Cheers.

 

[VicS]

If its a WSC it has a two jet Amal carb
You change the jets for different fuel mixes... thats what you need the special box spanner for.
The reference to "needles" applies to Villiers carbs

Take care with the Amal carb. Some parts are no longer available but are easily damaged. It's mentioned on the SOS website!

 

[Reptile Smile]

It's definitely an Amal carb... I think (if memory serves) you kindly supplied an exploded diagram of it for me in a different thread

 

[Tranona]

Suggest you clean the whole fuel system. For example there is a fine filter in the tap in the tank that gets bunged up with oil residue, particularly if you are using 10:1 - which is not necessary if you change the jet on the carb. If the fuel tap is the old type the cork seal may be perished so restricting flow. There is another filter in the inlet to the carb and you may also get gummy residue in the float chamber. You should be able to dispense with the choke almost immediately after starting and run the engine out of gear at a fast tickover to warm it up. If you have flooded it you will need to clean/replace the plug and make sure the lead and connections are OK. You can check the spark by holding the plug against the head while turning the engine over.

Clean fuel and a spark and it should run.

 

[VicS]

It's definitely an Amal carb... I think (if memory serves) you kindly supplied an exploded diagram of it for me in a different thread

The diagram is on the SOS website, although I might have scanned the diagram in the parts book if it was at a time when a lot of info on the website was lost.

 

[Reptile Smile]

Thanks to all for all advice offered so far.

It seems clear that the key thing to do is to clean the fuel supply route, though what still is to some extent confusing is why it is that both times it started and ran fine, but that the problem occurred (a) later on, and (b) when engaging gear..?

It seems that part of this might be something 'sticking', and I'm wondering if this might be either the float or the float needle. The problem is I don't really understand the function of either - can anyone explain how they work in the Amal Jet carb? Also, to clean the float/float needle/float chamber, is it just a matter of taking off the top cap from the float chamber?

Cheers

 

[VicS]

Possibly running a bit lean due to dirt in the jet ? Ok until you put some load on it then just to lean to keep going ??

The float works by lifting the "needle" to which it is fitted. This closes the valve at the bottom of the float chamber when the correct level is reached .
Dirt in this valve would lead to flooding.

Check the jets, check the filter on the bolt that holds the float chamber to the mixing chamber body.

Take great care when removing the jets and with the float chamber retaining bolt. If you damage the mixing chamber body you are stuffed as as new ones are no longer available.

The website has a diagram of the carb
http://www.saving-old-seagulls.co.uk/faq/images/amal 2 jet diagram.jpg

and also instructions for making a jet removal tool. See the FAQs section Its a5mm square box spanner

 

[Niander]

You can unblock the jets easy without taking them out
you can use fine copper wire if blocked
strip the carb and clean it in clean petrol
blow it all with compressed air if you have it
make sure the 2 jets are clear..hold it up to the light with out the slide in place
should see light through 2 holes 1 bigger than other
good carb amal 2 jet
then clean and gap the points
make sure you have a good spark

 

[tigr]

check fuel supply clean and good plug

Hi, I have found the most common hassle with seagulls is the fuel system gets gunked up. Make sure everything is cleaned out, especially the filter in the tank, and if you have a good spark life should be good. There is talk of changing the points gap to alter timing but I have not tried this. Details on SOS site, the site is great and a lot can be learnt.
I have used all sorts of two stroke oil but now use the nice marine stuff as I find it does not smoke so much, also it smells different and I sort of like the smell...
I have noticed though is that some plugs get more sooty than others, I have bought some new for my engines but noticed they send a replacement to the original NGK A6. What they normally supply is an AB6 which should be the same but with need a different size plug spanner, but I have found they seem to soot up more than the A6, but this could be my imagination.
Being keen to avoid hassles I use a A6, but they are getting harder to find so I have bought a good stock, if you need one I can supply.

 

[TrueBlue]

I have noticed though is that some plugs get more sooty than others, I have bought some new for my engines but noticed they send a replacement to the original NGK A6. What they normally supply is an AB6 which should be the same but with need a different size plug spanner, but I have found they seem to soot up more than the A6, but this could be my imagination.
Being keen to avoid hassles I use a A6, but they are getting harder to find so I have bought a good stock, if you need one I can supply.

Folks no longer play with plugs and have lost the art - or don't understand the heat ratings. The A6 works because it's designed to burn off the soot....

Thanks all for ongoing suggestions.

TrueBlue, are you saying that in cleaning the float chamber and fuel pipe, it stopped the 'start cold/not start warm' problem, or that this persisted even when you'd done it?

Bit of a Curate's Egg - yes the problem stopped but recurs, so I have to clean it once or twice a season. Mine's a 40+ with the Villiers carb: so easy to strip down, just a pain when you're doing it in the dinghy and with clean clothes on...

Oils -
(all very IMHO)
In the days when the 'gull was designed lubricants were pretty basic. In fact the basic engine was designed for wartime use, so perhaps the bearings and fuel mix were designed for the worst possible case. Hence (partly) the 10:1 mix.

Since then lubricants have improved - better film thickness and adhesion meaning that engines can run at greater dilutions. At the same time bearing sizes were increased - ? to spread the thinner oils ? However the mix remained at 10:1. So that's why later engines will run at 25:1 even though the recommendation was for 10:1. It's all on the SOS site.

Gumming -

I've had nothing but teeth sucking "shouldn't do" from experts. My guess is that the latest oils - and you can't buy anything else, are really designed to run modern engines with roller bearings (not plain bronze as in the 'gulls) at up to 100:1.
So with quite heavy mixture of 20, 25:1 (A very nice man at Moulsford who is on a level with John at SOS suggests perhaps 20:1 is safer) reacts with modern road fuel producing the "precipitation".

The strange thing for me is that it only happens when the boat's on the water - constant motion? and not over the winter when I leave the engine(s) in a shed.

 

[Tranona]

There were many reasons for the 10:1 mixture. The original oil used was SAE30, perfectly adequate for lubrication purposes and also for producing a seal in the "loose" plain bearings. Side benefit was that not all oil was burned so left a fine residue over the whole engine. This helped protect them in the long periods of inactivity - remember they (the 105 anyway) were designed to power landing rafts for the invasion, so they spent most of their life in the bottom of the boat in readiness for the one off use. The heavy oil mixture helped build compression when started after being left. Even now a quick squirt of oil into the intake will help a reluctant engine start.

For lubrication purposes 25:1 is fine. The change in jet or needle is because the engine run too rich with fuel that has a higher proportion of petrol to oil, although some will run happily on the originals.

 

[tigr]

over winter storage

The strange thing for me is that it only happens when the boat's on the water - constant motion? and not over the winter when I leave the engine(s) in a shed.

Clutching at straws but do you leave the outboard laying down on it's tank over winter? Could it be that when fresh fuel is put in at the start it runs fine until the gunk from the back of the tank runs down to the filter.

Could be a reason.

 

[VicS]

Clutching at straws but do you leave the outboard laying down on it's tank over winter? Could it be that when fresh fuel is put in at the start it runs fine until the gunk from the back of the tank runs down to the filter.

Could be a reason.

Good heavens. Nobody would do that!

The Owners handbook quite clearly states:

When out of use the engine should be stored UPRIGHT ( vertically) as on the boat and kept warm.​