Villiers Coil Substitution

[Jerry In Maine]

just got home after getting a bottle of argon for the tig welder. to compensate for the cost i had to take the wife to the dress shop and sit patiently while paraded back/forth in various garb asking me the loaded question "does this make me look fat?"

tomorrow morning i'll assemble everything up solid and check for spark w/wo out the breaker points connected and will try to get a closer sense of when the plug fires in relation to tdc. i did a quick setup last night and wasn't able to get a spark so hopefully nothing's happened to the coil. everything was very loosly fitted so i'm really not suprised. if something did happen i'll buy another.

i think the flywheel/transplanted coil may be acting like the ignition setup in my chainsaw, which has to be the ultimate in simplicity...no points, no condenser.

i found contiunity from the coil to the lead i attached to the points with a dmm. since the core is grounded, and since the core and the "points" lead are common it would seem that the breaker points are having no effect unless the resistance between the two is so small that my test leads are swamping the reading. i suppose this could be the case if there's a low resistance winding between the two.

will know more tomorrow. if you can think of any measurements or tests you'd like done please let me know and i'll do my best.

[Jerry In Maine]

for those who had interest in this experiment:

I'm away from home for a few days visiting with an uncle who became ill. This old codger drove landing craft onto the beach at Normandy on D-Day. In fact his brother (recently passed away) was there as well jumping out of those landing craft and made it up the beach some distance before he caught shrapnel from a gernade.

My grandmother had 4 blue stars in her front window during the war - one for each of the 4 sons involved in the fighting. "Uncle Pete" is the last one left.

Most likely the old coot will come around and go on for another 10 years - but you never know, so I'll hang out here for a few days then make the 600 mile trip home and pick back on on the Seagulls.

[Jerry In Maine]

Got home from what turned out to be a 1400 mile round trip, and soon as I got up next morning I went to work and got the chinese motorcycle coil installed on the Villiers ignition plate...and it works....sorta...I get a nice spark when spinning the flywheel by hand, but only when its turning counterclockwise - not when its turned in the proper clockwise direction.

Tomorrow I'lll make new brackets to mount the coil in the opposite direction. I hope that this will get it to fire when the coil is spun clockwise. Then I'll set this "hybrid" ignition on a working motor and try to get it started and find the proper timing if it's not correctly timed already.

I did wind up mounting the brackets with 8-32 cap screws. The brackets I made first were of angle iron which would have welded easily. The brackets turned turned out smaller that I had planned though and thin metal sheet was more in order, but it tended to burn through when welded.

Here's a pic of what I have now.

It's backwards, but it works.

[Collector Inspector]

This is all, really COOL!

Elto coils are really small and have been thinking along these lines for ages.

Just have to find that "Magic" replacement "Diameter"..............

B

[phil]

Here's a coil about the same size as the Villiers coil, still quite pricey though.
http://store.eastcoastmarineservice.com ... &show=10&p
Look for the bendix-scintilla coil on the following page.

[Jerry In Maine]

so far this AM i've gone through a couple set of brackets to face the coil in the opposite direction with no luck. I'll get there - just takes considerable trial and error. I have to make sure the shaft bump that activates the points and the rotating magnets on the other side don't whack the coil.

Thing I've found so far:

If the metal coil is too long - or if it doesn't have the proper shape - you can cut it as needed, just use a Dremel style tool with a cut-off wheel. The metal core is usually laminated of many thin metal strips - and as its being worked it might separate a little and the laminations might fan out a bit. If this happens clean in alcohol, let dry, apply a little 'super-glue" and let it soak in between the strips then press in a vise until the glue cures.

Since you can cut the core you can use coils with coils of odd shapes. This might allow the use of coils from chain-saws, lawnmowers, weed-wackers and the like. You can also reshape the coil by cutting and then bolting the stub to a strip of iron in the shape that you need. Use ferrous metals for any brackets you might make since you need the magnetic flux created by the flywheel magnets passing by the iron cheeks to pass through your adopted coil. Make all connections tight.

Careful when working the metal in the core that you don't get it too hot. Operations like cutting and grinding can create considerable localized heat when might melt or at least soften the insulation on the internals. In short, just "go easy" and you should be fine.

Before you spend time on mounting make sure the coil is orientated properly. Try to get in in place temporarily to determine the direction it has to face in order to spark with proper flywheel rotation. I don't do that and it costing me time now.

When I'm done (hopefully soon) I'll do a dry run then disassemble and use thread-lock compound as I reassemble. Last thing you want is loose parts to be slinging around under that flywheel.

Back to the shop...will hopefully have good news soon.

[Charles uk]

This ignition is almost certainly a CDI & as such should not need the points, according to Peter 40tpi otherwise the polarity would not matter, are the points connected to the stop button terminal in your picture?

[Jerry In Maine]

what i know so far with the coil installed in the original direction:

plug will fire when the flywheel is spun counterclockwise and points connected to the terminal on the coil
plug will not fire when flywheel is spun clockwise and points connected to the terminal on the coil
plug will not fire when flywheel is spun in either direction if points are disconnected from the terminal on the coil

when i get everything mounted up solid i'll run those tests again to make sure I'm not mistaken. I am sure though that with the coil installed in the original direction I get spark only when the flywheel spins counterclockwise. A few posts back I mentioned that I had might have damaged the coil because I wasn't getting spark. I was about to give up when I spun the flywheel in the other direction while holding the plug wire. I got a nice jolt, so i put the plug back in a saw it spark.

[Jerry In Maine]

After several gyrations in testing various configurations of coil mounting direction and connecting/disconnecting the points, I don't think this particular coil will run a Seagull unless you want it to run backwards.

Made a nice mounting on the lathe which consisted of two stubs the same size as the Villiers coil core. Ground down flats on the ends and drilled/tapped them for a 6-32 screw. Screws passed through the mounting holes in the new coil and were pulled tight to the flats. The assembly then installed just like the old Villiers unit.

With the coil now reversed, I can connect the points and get a spark at the plug gap - but still only in the counter-clockwise direction.

I can disconnect the points and get voltage in either direction - but only enough to feel. There's not enough to jump the gap of the spark plug.

From what I've read magnetos can have varying numbers of magnets in the flywheel, and I think that this coil might be intended for a different magnet configuration. Encouraged by the fact that this ALMOST worked, I'm looking for another coil(s) to try. If anyone finds one online they think might have a chance let me know and I'll give it a shot provided its not too expensive.

[Horsley-Anarak]

One like this may be worth a try?

http://cgi.ebay.co.uk/New-Ignition-HT-C ... 2c54d3f6e9

H-A

[Jerry In Maine]

just bought this one:

http://cgi.ebay.com/ebaymotors/ws/eBayI ... MEWAX%3AIT

might be a tight fit and i'll have to rework the core a little - but at around $12 it's cheap entertainment. besides - i got sweat equity in the project now and if i don't get something working it'll haunt me.

guess i'm just odd that way...

[Charles uk]

HA isn't that just a spark coil? Peter 40tpi should be able to answer that.
What I mean is this just a secondary coil that requires a primary or a battery to provide the energy for it to stepup the voltage.

[Jerry In Maine]

i realized that i hadn't yet tried the coil with the "extra" lead grounded. tried that with about the same results.

to summarize this coils operation:

I can get at least enough voltage to feel with the flywheel turning in either direction, with the coil mounted in either direction and with the "extra" lead either open or grounded. I get enough for a nice spark only with the flywheel turning counterclockwise, coil in either direction and with the points connected to the "extra" lead".

i think the coil would run a Seagull without points connected and with the flywheel turning in the proper direction if the output was just a bit stronger. the voltage i feel (when not enough for a spark) is substantial, and while i can't quantify its voltage i've been zapped enough to tell that is close.

[Jerry In Maine]

I seem to have success this morning using a Honda "COP" (Coil Over Plug) unit and an easily hand-wound generator coil. Ordered the coil off ebay and got it yesterday. I wound a simple generator coil (125' of #22 magnet wire) on the metal-rod core of the defunct Villiers magneto coil. Connected one end of the coil to the points, the other to the primary of the COP, spun the flywheel by hand and got a spark from the plug.

I plan to add a few turns to the generator coil - since I have plenty of room on the core and another spool of wire handy. This should increase the output voltage to the COPs primary and get me a stronger spark, although I think what I have now is enough...Once done I'll set the rig on a motor (everything is on the test bench at the moment) and see if it run. At this point I'm fairly confident it will - but I don't want to jinx myself

The idea here is to come up with a method for the average Seaguller (like me) to get a motor with a defunct coil back in operation (with easily scrounged parts and a little time), at least until he can locate another Villiers coil - but I see no reason that this mod can't be left in place and relied on for normal use. It should not require any permanent changes to the motor (no hole to drill, etc), and if parts have to be mounted externally they should be small and not horribly distract from the motors original appearance.

Progress is hampered somewhat by a right middle finger thats a bit shorter than it was yesterday. I have a crankcase/crankshaft/ignition plate/flywheel all mounted in a vise as a test platform. Was spinning the flywheel with a finger watching for spark when my finger slipped through one of the holes in the top of the flywheel bringing the assembly to a full and sudden stop. Blood ran, a small chunk of finger flew across the room and I yelled a few words that I'm not exactly proud of

More info later...it hurts to type!

[Jerry In Maine]

notes and pics...

reversed the coil's connections and the spark got a bit stronger. in the previous post i mentioned that i was going to add additional wire to the generator coil - but i think i'll try running a motor with what i have now.

the home-brew generator coil is just 125' of #22 magnet wire wound on the defunct villiers core rod. nothing high-tech here. i'd like to say that the 125' length was arrived at by applying a complicated algorithm in designing the coil, but actually its simply the amount of wire i had on the spool at the time. btw: the job of this coil is to generate sufficient current to power the separate ignition coils primary winding. one end of our homebrew coil connects to the points - the other end connects to the adopted honda ignition coil.

I've been testing just by spinning the flywheel by hand. max speed i can obtain is only about 2 rotation/second - but i get decent spark regardless. hopefully the spark will be more intense at idle speed and above. keep you finger out of the flywheel if you try this. i slipped and cut enough meat off my finger to make a sandwich!!

the honda ignition coil is too big to hide under the flywheel. if i use it on a motor i'll likely mount it under the tank.

Test jig. keep your fingers out of the flywheel holes when turning by hand!!!

Honda CBR600 "Coil Over Plug" ignition coil

Home-brew generator coil. Its 125' of #22 magnet wire wound on the original Villiers magneto core rod. Covered overall with tape to keep it from unwrapping.

more after i try to run a motor with this rig...likely tomorrow.