After reading the site and emailing John, I have done the "Drill remagnetising" of my engine and finally got it running but very eratically. When I run the motor with the drill, the spark was not consistent and strong and became more absent the higher the revs, so I opened the points gap to 0,55mm and the spark just came alive in a miniature version of arc welding. I put the spark plug back and started the motor and it went first pull, but clearly only firing every fourth revolution or so and splutters to a stop. As for running there is no noticeable difference between the different gaps settings. I prefer the bigger gap purely on the fact that the spark is much more consistent and stronger with the drill.
I have the feeling that as soon as the motor starts running, the vibration causes the spark to be lost. I've checked the leads etc. as best as I can, but can't pinpoint the problem. (I've adjusted the needle as well,--Villiers #3 needle-- just for fun, but both way's n or out causes the motor to stop, so I guess I'm at optimum.) The motor was stripped by the previous owner who could not get it running or responding to throttle when it did splutter. I suspect that things where put back wrong. (The exhaust was wrong way around for a start.) My assembly diagram got lost somewhere, so please help me with the following questions.
The screw below the base next to the HT lead was loose, I've never figured out what it was for. I turned it back in, but its long and how much should it be tightened? Should there be a washer or something?
When I pull of the HT lead under the base plate, there is just a little brass/copper spring with a little dome inside. Should there be some similair connection on the coil side that it should contact?
I've noticed that the points gap have changed slightly after running the motor under power. There is two screws near the points, the centre one, seems to rotate in some sort of oval pattern if I loosen the outer one, but the outer one needs to be fairly tight before the centre screw will actually adjust the points. What is the correct procedure for setting the points? I loosen the outer screw a bit, then fiddle the inner screw, then fasten the outer screw. Somehow or the other I don't think this is correct though. What is actually causing the points to open? There must be some mechanical link somewhere?
Hope I'm not asking too many questions! Regards
Erractic firing, info needed
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Re: Erractic firing, info needed
Hi,
first, yes that's how you adjust the points. One screw is the adjusting cam, the other fixes the position.
Second, the HT lead plunger should be against a copper button on the coil. Look in the hole and you should see it.
Third (and your problem I think) the long screw should fit in a dimple, fixing the timing position. Take out the screw and poke a suitable item in the hole, rotate the backplate until you find the dimple and refit the screw.
All should be ok from there.
Regards
Phil
first, yes that's how you adjust the points. One screw is the adjusting cam, the other fixes the position.
Second, the HT lead plunger should be against a copper button on the coil. Look in the hole and you should see it.
Third (and your problem I think) the long screw should fit in a dimple, fixing the timing position. Take out the screw and poke a suitable item in the hole, rotate the backplate until you find the dimple and refit the screw.
All should be ok from there.
Regards
Phil
Re: Erractic firing, info needed
Just a thought, a bigger gap might give a more visible spark but not necessarily a better one. Under compression in the cylinder a lot more oomph is needed for the spark to jump the gap, higher resistance etc. I strongly suggest a correct gap, those old boys at Seagull knew what they were about, until it came to my Kingfisher, that is. But that is another story!
Good luck.
Good luck.
Re: Erractic firing, info needed
Thanks for the replies Phil and Sophie. I will set the spark gap back where it was.
By the "long screw" you mean the one below the flyweel just above the crankcase? If that be the case, I will give it a bash, because looking into the that screwhole I see only threads all the way down and it ends rather blunt. Does the flywheel need to come off before turning the backplate because a preliminary wriggling just did not seem to move it with the flywheel attached. (I got only my own pair of hands to remove flywheel, else I will have to wait to Wednesday.) I will only be able to follow up late today or tomorrow.
I checked the HT, and everything there seems ok. What grade is the petrol you use? Ours is 95 octane. I doubt if it will make much difference in any case.
By the "long screw" you mean the one below the flyweel just above the crankcase? If that be the case, I will give it a bash, because looking into the that screwhole I see only threads all the way down and it ends rather blunt. Does the flywheel need to come off before turning the backplate because a preliminary wriggling just did not seem to move it with the flywheel attached. (I got only my own pair of hands to remove flywheel, else I will have to wait to Wednesday.) I will only be able to follow up late today or tomorrow.
I checked the HT, and everything there seems ok. What grade is the petrol you use? Ours is 95 octane. I doubt if it will make much difference in any case.
Re: Erractic firing, info needed
Work changed a bit in schedule, so I took the Seagull for some fresh air...
Dimple now fixed in position. It was correct in the first place, only I did not know what to look for at first. I discovered the HT lead just pushed into the elbow underneath the flywheel. (After I turned the backplate without removing the HT lead...) There was electrical contact, but a sure sign of trouble if the motor shakes when running. Fixed it by turning the screw into the HT lead, will need a new screw though the old one's thread is melted in places, i.e. it must have sparked inside the elbow to melt it. Now its sits tight! Lead is a little short though being pushed further inside the elbow piece.
Motor started, but quickly started firing erratic again. It seems better when cold for the first minute or so.
Just for fun I removed the flywheel. (With only my own hands available...) Things looked fine and tight, so I put it back, once again starting was easy, smooth running initially, but soon bugged down to a rattling "fire as you please" pattern. (Yes I do open the choke!) I stared at the brand new spark plug provided by the previous owner. Its a Champion D23. Tick tick tick goes my brain, I'm sure it should be D19? Wrong again, D16 is asked for. Will change it and see what happens. I've read that the Champion D9 is also good and a hotter plug, which may help keep the plug from being gunged up. (My plug always seem to collect oil...)
Would it be better to use a hot plug in colder weather/water or is it just the same?
Dimple now fixed in position. It was correct in the first place, only I did not know what to look for at first. I discovered the HT lead just pushed into the elbow underneath the flywheel. (After I turned the backplate without removing the HT lead...) There was electrical contact, but a sure sign of trouble if the motor shakes when running. Fixed it by turning the screw into the HT lead, will need a new screw though the old one's thread is melted in places, i.e. it must have sparked inside the elbow to melt it. Now its sits tight! Lead is a little short though being pushed further inside the elbow piece.
Motor started, but quickly started firing erratic again. It seems better when cold for the first minute or so.
Just for fun I removed the flywheel. (With only my own hands available...) Things looked fine and tight, so I put it back, once again starting was easy, smooth running initially, but soon bugged down to a rattling "fire as you please" pattern. (Yes I do open the choke!) I stared at the brand new spark plug provided by the previous owner. Its a Champion D23. Tick tick tick goes my brain, I'm sure it should be D19? Wrong again, D16 is asked for. Will change it and see what happens. I've read that the Champion D9 is also good and a hotter plug, which may help keep the plug from being gunged up. (My plug always seem to collect oil...)
Would it be better to use a hot plug in colder weather/water or is it just the same?
Re: Erractic firing, info needed
Just a comment to say that with Champion plugs the higher the number the hotter the plug, so the other plugs you have mentioned will be hotter than D9.I've read that the Champion D9 is also good and a hotter plug
(BTW opposite way for NGK plugs. lower numbers are hotter)
Re: Erractic firing, info needed
New plug is installed. Cost a bomb, but at least it seats properly. Previous plug was hard to screw in by hand. The plug made only a small difference initially. I set the points to 0,55mm where the motor appear to run best, but dunking it back in the water it was back to spluttering. I knocked the flywheel a bit, and it start running better, maybe the magneto need more surface area past the coil? Dunno, but it did not solve the problem.
So I was fiddling with the mixture, turned needle in and out, inner was better, but still bad. Then it struck me, maybe I should remove the plug, turn it TDC by eye, and then set points to 0,5mm? I did that and then the motor was purring like a cat with adenoids! Stupid, I can't imagine why I did not do this in the first place. I simply turned the flywheel to where the points was open max, and set it in that position. Somewhere I've read that it corresponds to TDC, or I may simply have my marbles mixed. Anyway its running beautifully now with both plugs and points set at 0.5mm.
Sad part.
I discovered the fuel pipe is leaking slightly at the carb's inlet. I fiddled with it, and the leak got worse.... I fiddled some more and its back to a slow drip. This is definitely recent, I suspect being manhandled I must have bumped it. Is it possible to fix that connection on the end of the pipe? It looks like its been crimped on.
One more question. Running the carb dry at "put-it-back-in-the-garage-and-go-find-something-to-eat-time" I got two mighty backfires and two huge palls if smoke coming from the carb. (The dog almost climbed a tree, funny that, he is not the slightest bit disturbed by fireworks...) My previous Seagull never did that, anything I should check?
Regards
So I was fiddling with the mixture, turned needle in and out, inner was better, but still bad. Then it struck me, maybe I should remove the plug, turn it TDC by eye, and then set points to 0,5mm? I did that and then the motor was purring like a cat with adenoids! Stupid, I can't imagine why I did not do this in the first place. I simply turned the flywheel to where the points was open max, and set it in that position. Somewhere I've read that it corresponds to TDC, or I may simply have my marbles mixed. Anyway its running beautifully now with both plugs and points set at 0.5mm.
Sad part.
I discovered the fuel pipe is leaking slightly at the carb's inlet. I fiddled with it, and the leak got worse.... I fiddled some more and its back to a slow drip. This is definitely recent, I suspect being manhandled I must have bumped it. Is it possible to fix that connection on the end of the pipe? It looks like its been crimped on.One more question. Running the carb dry at "put-it-back-in-the-garage-and-go-find-something-to-eat-time" I got two mighty backfires and two huge palls if smoke coming from the carb. (The dog almost climbed a tree, funny that, he is not the slightest bit disturbed by fireworks...) My previous Seagull never did that, anything I should check?
Regards
Re: Erractic firing, info needed
See the FAQ pag for flywheel removal, basically, don't!
The gap at the plug, a D16 by preference, is 20 thou or 0.5 mm, 50 on a metric set of feelers.
Re the plugs, the hotter plug is the D21, if you can find one. The D9 is being touted as a good Seagull plug by someone who has a shed full to offload on unsuspecting Seagull owners, beware. It is not recommended at all.
I have run D16s for years, give no problems. Got them for £5.00 here still....
Re your motor, is there bay any chance any 'wobble' in the ignition backplate? If there is that is what is causing back fires and intermittant spark maybe. another reasonis the screw securing the backplate to the case is in the wrong place, it should only fit in the one dent in the case. do not over tighten....
another reason for backfires is weak mix. If the bearings are worn or there are bubbles appearing at the horizontal crank case joint, air may be sucked in and fuel expelled, both weakening the mix enough for backfires.
Best of luck with the Seagull, that should give you a few more things to check!
Regards,
John
The gap at the plug, a D16 by preference, is 20 thou or 0.5 mm, 50 on a metric set of feelers.
Re the plugs, the hotter plug is the D21, if you can find one. The D9 is being touted as a good Seagull plug by someone who has a shed full to offload on unsuspecting Seagull owners, beware. It is not recommended at all.
I have run D16s for years, give no problems. Got them for £5.00 here still....
Re your motor, is there bay any chance any 'wobble' in the ignition backplate? If there is that is what is causing back fires and intermittant spark maybe. another reasonis the screw securing the backplate to the case is in the wrong place, it should only fit in the one dent in the case. do not over tighten....
another reason for backfires is weak mix. If the bearings are worn or there are bubbles appearing at the horizontal crank case joint, air may be sucked in and fuel expelled, both weakening the mix enough for backfires.
Best of luck with the Seagull, that should give you a few more things to check!
Regards,
John