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wont spark

PostPosted: Fri Dec 09, 2016 9:50 pm
by JBG584
Hi
Parking scoot up 3 months ago ,gone to start no go took plug cap of and plug out held lead against engine no spark.I fitted new points and condenser in August any ideas.
Thanks Ray

Re: wont spark

PostPosted: Fri Dec 09, 2016 11:18 pm
by Raveydavey
Check the ignition is actually on. Wouldn't be the first time.
Make sure the coil is getting a spark, green wire from stator.
Check earths

Re: wont spark

PostPosted: Fri Dec 09, 2016 11:40 pm
by HxPaul
Parked scooter up 3 months ago,did you try to start it immediately or was it left for 3 months before you tried to start it,if its the latter has it been left in a misty,wet or damp atmosphere.If it has the wiring junctions could be corroded.

Re: wont spark

PostPosted: Sat Dec 10, 2016 10:26 am
by johnnyXS
like Davey says start at the beginning.

Change your spark plug first for a known good one. Check the gap and file the electrode to a nice straight sharp edge.
Check both your low tension connections on your ignition coil .
Make sure both ends of your high tension lead are screwed right in and making a good connection.
Disconnect the green wire going from the junction box to the headset in case you have a short somewhere in the loom or your kill circuit.
Pull the green stator wire out of the junction box and hold the terminal close to a clean earth and check if you are getting a spark from the stator coil.
Stator coil ok but still no spark at the plug ? substitute a good ignition coil . One from a ves*a or car will work.

No spark then chances are the condensor has gone AWOL or there is a problem with your points or stator wiring so you'll need to remove the stator :roll: :cry:

Re: wont spark

PostPosted: Sat Dec 10, 2016 10:48 am
by Tractorman
Could also the points are not working correctly due to the lay up, condensation or fouling.

Re: wont spark

PostPosted: Sat Dec 10, 2016 11:31 am
by CHRIS in MARGATE
Rub a file through the points.

Re: wont spark

PostPosted: Sat Dec 10, 2016 12:24 pm
by johnnyXS
condensation is a killer this time of year isn't it . My car engine was absolutely saturated with condensation after the recent freezing fogs.
Saying that.......... it shouldn't stop you geting a spark unless theres a electrical short somewhere.
I sometimes heat my plugs in the oven if its not starting or use Easystart of course :lol:

Re: wont spark

PostPosted: Mon Dec 12, 2016 6:43 pm
by JBG584
thanks for help tried it without plugcap lead end just fraction away from earth no spark.Series 2 so no ignition. Been in garage,will check wiring

Re: wont spark

PostPosted: Fri Dec 16, 2016 8:52 am
by Raveydavey
JBG584 wrote:thanks for help tried it without plugcap lead end just fraction away from earth no spark.Series 2 so no ignition. Been in garage,will check wiring



A multimeter is your friend with this type of thing; check each stage for power output, and isolate the cause. If it's worked before it's probably wired ok, although do double check the earths.

Re: wont spark

PostPosted: Fri Dec 16, 2016 10:27 am
by johnnyXS
JBG584 wrote:thanks for help tried it without plugcap lead end just fraction away from earth no spark.Series 2 so no ignition. Been in garage,will check wiring


Well now you need to work your way through the whole ignition circuit from your stator ignition coil (green wire) to the spark plug ;)

Pull the green stator wire ( wire coming out of the mag housing) out from the junction box and hold that close to a good clean earthing point and check that for a spark.
If you have no spark at that point then you are going to need to check your points, condensor and the ignition coil on the stator together with the associated wiring .

If you have a spark at the junction box then replace the green Stator wire but pull out the other green wire going to the headset . This eliminates and isolates the kill switch , ignition switch and wiring loom , headlamp junction block etc .
If you still have no spark then the problem lies somewhere between the junction box and the ignition coil or between the coil and the spark plug or its the coil itself

Re: wont spark

PostPosted: Fri Dec 16, 2016 2:18 pm
by coaster
Oh how I hate points ignitions and damp weather, you ca never be absolutely certain that it isn't the damp causing leakage to earth. Good call be JonnyXS about the kill switch, certainly one of the first checks to be made. When checking if there is any juice from the stator green wire, you must rub the terminal against a good earth as the engine is kicked over (best with the spark plug removed) get an assistant if necessary. You should get a yellowish spark but it won't jump ant sort of gap as it's only 30 or so volts. If still no spark I would suggest cleaning the points with wet&dry over a feeler gauge and if that doesn't work, a good squirt of WD 40 into the magneto and all other connections including the coil.

Re: wont spark

PostPosted: Sun Dec 18, 2016 1:35 pm
by JBG584
thanks will try all these and let you all know for future
Ray

Re: wont spark

PostPosted: Fri Jan 20, 2017 9:21 pm
by JBG584
Scoot wont start no spark changed plug 2/ took of cap no spark 3/ removed green stator wire from junction box earthed had a small spark as only 30 volts at this point,so power from condensor etc. 4/ replaced wire,
removed green wire to headset still no spark.5/ checked for small spark on feed to coil ,had small spark so indicates power to coil. 6/ changed coil for another but dont know if this one is ok as its been knocking around for 56 years.Checked with multimeter getting about 4.5 from low and 11.8 from plug lead side.Any ideas unless someone could lend me a working coil to try and eliminate this,I live in Marcham near Abingdon ox136nt
Cheers Ray

Re: wont spark

PostPosted: Fri Jan 20, 2017 10:24 pm
by Warkton Tornado No.1
Coils don't normally fail, though if your condenser is on the way out, you can still get a spark...

As you're getting power from the stator, connect your coil(s) properly, then insert new, copper cored, or cut back the existing, HT lead to ensure a good mechanical/electrical connection.

Remove the plug cap & cut back the HT lead to expose bare wires.

See if you get a spark kicking over, or, if you're really brave, just hold it & 'feel' for a shock as you kick over.

If both coils have failed, report back, as I can lend you one if therte's none nearer.

Good Luck! ;)

Re: wont spark

PostPosted: Sat Jan 21, 2017 10:02 pm
by missing lynx
check your kill button remove the green wire from the regulator and see if it sparks if it does it's the kill button if not it's ether the points the condenser a brake in stator wiring or damp

Re: wont spark

PostPosted: Sun Jan 22, 2017 4:58 pm
by grandpa
Hi JBg
Make sure your engine is earthed Make sure HT coil has good earth.
Clean points then with a small piece of paper insert into points turn flywheel and make sure points grip paper this shows points closing.
Green wire from stator will spark if held close to engine need dark garage to see( weak spark)
Remove any green wires from HT coil and connect a length of wire directly from green stator wire to HT coil this will bypass any junction box and iignition switch..When or if engine runs short green wire to earth to switch off
Good luck
Grandpa

Re: wont spark

PostPosted: Sun Jan 22, 2017 5:34 pm
by CHRIS in MARGATE
Point a fan heater or hair dryer through flywheel on to stator plate to drive put any damp. Run a small file through points and as said make sure they grip a cigarette paper.

Re: wont spark

PostPosted: Tue Jan 24, 2017 1:28 am
by JBG584
Hi
thanks for ideas will work through them all will let you know what I find

Re: wont spark

PostPosted: Tue Jan 24, 2017 8:35 pm
by JBG584
Hi
Does anyone know what the multimeter readings from the HT coil flow from + and- and from HT lead to the + side of the coil
Ray

Re: wont spark

PostPosted: Thu Jan 26, 2017 12:37 am
by JBG584
Hi
Sussed it- At last it turned out to be the wire that goes from the points to the condenser somehow it had moved and was rubbed through by the flywheel so I was getting small spark from the green wire as it passed the gaps in the flywheel but not continually,and the spark took the easier route when the coil put in the demand for power.
Thanks to you all maybe this may come in useful if anyone else has a similar problem.
Ray