No spark from Villiers coil

[one_riff_brian]

I've checked the resistance from the HT stud to the backplate- I'm not getting anything until I crank the meter up to the 20M range. AIUI, it should be around 5k Ohms, so I think it's a safe assumption that I've got an open circuit HT winding. Now, assuming the LT is intact, is it possible to connect in an external coil?- It seems to be universal practice on motorbikes.

[Vic]

The old Villiers coils have a gap in the HT connection so you wont get continuity with a meter.

[Charles uk]

Old Villiers motor cycle coils might well have a gap in the secondary windings,
but no Villiers coils used by British Seagull ever had one!
This applies to both the earlier M1030x16 (pre 1946) or the post 46 M1634,

If you have a Villiers coil that has no continuity between the ht connector & earth, then you either have a retrofitted non standard coil or you have a break in your secondary windings which is small enough for the spark to arc across at hand pulling revs to start, at running revs there will be a bit more voltage so the spark can jump a bigger gap.
Unfortunately this arcing generates a lot of heat, damaging the adjacent windings up to a point where the coil dies or you just can't pull the rope fast enough to start the motor.

If your Seagull is fitted with a Villiers coil that you can't get a reading from, but still starts I would recommend not taking your boat any further from land than you can comfortably row in the tide & weather conditions of a worst case scenario.

[Vic]

Old Villiers motor cycle coils might well have a gap in the secondary windings,
but no Villiers coils used by British Seagull ever had one!
This applies to both the earlier M1030x16 (pre 1946) or the post 46 M1634,

Thats odd

I have a Villiers Mk2 Midget engine which has a M1634 coil. That appears to have a safety gap in the secondary winding. Certainly no continuity when tested with a meter.

The engine starts easily and runs well, better than most Seagulls, so presumably it is not a faulty coil !

[Charles uk]

Can you post some pictures of this "safety gap" so we can see what your talking about, it must be external to the secondary winding as there's no provision for heat loss inside the cardboard case.

I have at least 12 Villiers coiled Seagulls all of the ones that run have measurable resistance coils.

We on this forum have never seen a "safety gap" coil fitted to a Seagull & in fact one of this forum's members Peter 40 tpi has carried out several CSI investigative disassembly's of Villiers Seagull coils. So that if it proves necessary we have the full technical specification to have them re manufactured especially the M1030 as there is no Chinese clone available.

So correct me if I've got this wrong the coil your talking about is not in a Seagull but in a Villiers motor.

Here's a paragraph I've just stolen from the Villiers spares site.

"Just bought a used ignition coil ?
Some people have the illusion that buying 50/60 year old coils are a bargain, WRONG, most if not all around that age are full of rotten green copper wire no thicker than a human hair, If you test one with a multi meter & find a circuit through the windings it still doesn’t mean it will function properly, some don’t show a circuit & still make a spark, WHY?, because the current is jumping across a break in the windings & very soon that gap will widen after getting hot and the current wont jump anymore & the coil will fail, Also some will show a spark at a plug laying on the engine, but when you screw the plug in it wont spark under compression, the compression can stifle the spark if its weak."

Here on this forum we are trying to remove some of the mystery surrounding these quaint old outboards, not add too it!

[Vic]

No its not external.

[Charles uk]

Enough of that we're not shedding light on the dead Villiers on a Seagull problem,

Cement mixer motors with magical coils are not in our remit on this thread.

[Vic]

I only report what I have found!

I don't understand the reference to cement mixers or the reason for making such a ridiculous remark!

[Horsley-Anarak]

http://cgi.ebay.co.uk/BENFORD-VINTAGE-P ... 0712954237

Note the type of petrol engine .

The villiers magneto seagull engines that I have, all have continuity through the HT windings.

The ones that did not have continuity, either ran intermittently or not at all. This was due to breaks in the secondary winding.

If you take a villiers coil from a seagull apart, the end of the secondary winding is connected directly to the HT stud.

I have not found a gap.
H-A

[one_riff_brian]

I have a Villiers Mk2 Midget engine which has a M1634 coil. That appears to have a safety gap in the secondary winding. Certainly no continuity when tested with a meter.

Safety gap? For the safety of who or what? I would ask: how are you checking the continuity? What sort of meter, what range?

Re: my own progress- I'm currently using an external Lucas coil and power supply connected to the Villiers breaker to get a spark. I'm getting a very nice spark with the plug out, but it seems to be happening at around 60 degrees before TDC. That can't be right, surely... or can it? Hey, I'm new to this.

[Charles uk]

Seagull ignitions spark at about 23 degrees BTDC + or - 2 degrees, the points gap will affect this a little.

At 33 degrees BTDC it will be getting harder to start but will run well at peak revs 4000+ but not tick over too well,
at 13 degrees BTDC it will start very well tick over well at very low revs, but not run very cleanly at high revs.
All these statements are based on a Seagull powerhead that is in good mechanical condition.

[one_riff_brian]

Seagull ignitions spark at about 23 degrees BTDC + or - 2 degrees, the points gap will affect this a little.

At 33 degrees BTDC it will be getting harder to start but will run well at peak revs 4000+ but not tick over too well,
at 13 degrees BTDC it will start very well tick over well at very low revs, but not run very cleanly at high revs.
All these statements are based on a Seagull powerhead that is in good mechanical condition.

Very strange- I've got to be doing something silly- I'll have another look tomorrow.

one of this forum's members Peter 40 tpi has carried out several CSI investigative disassembly's of Villiers Seagull coils. So that if it proves necessary we have the full technical specification to have them re manufactured especially the M1030 as there is no Chinese clone available.

Now, that's interesting- roughly how much are the Chinese clones? What I'm thinking is: an LT winding only on the magneto core, connected to an external remote coil, opening up the possibility of extra power take-off auxiliary windings. Nothing destructive that can't be restored later.

For now, how do I get the bloody thing off? I assume that once you've got one polepiece off, it's easy. Is there a foolproof, nondestructive way of gripping the stud-headed counteresunk screws. Are there stainless replacements available?

[one_riff_brian]

Update... I've managed to get a spark using a temporary lash-up of a Lucas coil and battery, and timed it to about 22 degrees BTDC- about 35 mm on the flywheel circumference. I've stuck in a new NGK plug, squirted in a little bit of mixture, and given it a pull- nothing. I would have been content for now for a bang from the exhaust and some smoke, but nothing. I'm beginning to suspect the compression- i have had the head off. My questions right now are: what should the compression be, if I can get an adaptor to measure it, and is it the rings or the head gasket that are playing up? FWIW, I can turn the flywheel through TDC with just a finger and thumb on the dome nut.

[atoyot]

... I'm beginning to suspect the compression- i have had the head off. My questions right now are: what should the compression be, if I can get an adaptor to measure it, and is it the rings or the head gasket that are playing up? FWIW, I can turn the flywheel through TDC with just a finger and thumb on the dome nut.

If you can turn the flywheel through TDC with just finger torque on the dome nut, that's very weak compression indeed. If you've not yet put a couple of tablespoons of oil in the cylinder, try now. Put the engine on it's nose so the plug hole is straight up, and introduce the oil, then spin the flywheel around half a dozen times, and then re-insert the plug. If that doesn't make you have to work a bit harder, you may have stuck rings or worse. If it helps, great.

Once you get a compression tester on this, it'll depend on which block you have as to what's normal. I seem to recall an acceptable amount as something like 70lbs/sq.in. for the 64cc cylinder and around 30 for the 102cc - someone please correct me if it's different.

Which Villers ignition do you have, MK-I, MK-II etc (or what year is your engine)?


edit - here's a discussion on spark plug/compression tester adaptors. They're around.

http://www.saving-old-seagulls.co.uk/fo ... tor#p11479

[one_riff_brian]

I did the oil down the plughole check this evening- a little refinement. I checked with the plug upwards to let the oil seal the piston, and an old plug downwards to seal the head gasket. So what was it, head or rings. And the answer is.............................................both of them.

This engine is sicker than I thought.

So, head and barrel off, revealing the oil that escaped from the head gasket, and two very stuck rings, one of which perished in the attempt to free it. New rings and gaskets on order, thanks to all for the advice so far, and stay tuned for the next instalment. It'll all be worthwhile when it fires up.

Which Villers ignition do you have, MK-I, MK-II etc (or what year is your engine)?

It's a 1965 Forty Plus with an M1634E coil. I'm following the thread about cobbling in a motorbike coil with interest.