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Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 1:51 pm
by Martin20
anyone can help!
I'll try to keep as short as possible.
LIS 150, all standard. Still on 6 volt system.
Starting struggling to start a couple of weeks ago, and when it did start, it was running very rough, spluttering, dying on tickover, not revving etc! Thought it felt like an air leak, so stripped exhaust, top end, put it all back together, still same. Stripped again, still same!
There was intermittent spark at plug, but this disappeared altogether last week. Took green wire from stator, from junction box, kicked, and there was a spark. Ok, so must be coil! Borrowed a quality multimeter from mate, took coil off and tested. All good. 3.5 ohms at primary, and 16.5k at secondary. Put it all back together..no spark! New HT lead..no spark! Changed condenser for new one this morning, still no spark from HT, but still spark from stator!
Being somewhat electrically challenged, I have no idea what to do, or check next. (tried a spare working coil as well, but no joy!)
Anyone any ideas or advice?
Seriously thinking of ripping it all out and going electronic!
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 3:28 pm
by GTFOMWSC
Martin20 wrote: ↑Mon Jul 30, 2018 1:51 pm
anyone can help!
I'll try to keep as short as possible.
LIS 150, all standard. Still on 6 volt system.
Starting struggling to start a couple of weeks ago, and when it did start, it was running very rough, spluttering, dying on tickover, not revving etc! Thought it felt like an air leak, so stripped exhaust, top end, put it all back together, still same. Stripped again, still same!
There was intermittent spark at plug, but this disappeared altogether last week. Took green wire from stator, from junction box, kicked, and there was a spark. Ok, so must be coil! Borrowed a quality multimeter from mate, took coil off and tested. All good. 3.5 ohms at primary, and 16.5k at secondary. Put it all back together..no spark! New HT lead..no spark! Changed condenser for new one this morning, still no spark from HT, but still spark from stator!
Being somewhat electrically challenged, I have no idea what to do, or check next. (tried a spare working coil as well, but no joy!)
Anyone any ideas or advice?
Seriously thinking of ripping it all out and going electronic!
Think you sort of come to the right conclusion at the end go electronic tbh
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 4:09 pm
by Doom Patrol
You could need your flywheel re-magnetising.
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 4:50 pm
by Martin20
Doom Patrol wrote: ↑Mon Jul 30, 2018 4:09 pm
You could need your flywheel re-magnetising.
Thanks for suggestion Doom Patrol, but this had it done this time last year, so hoping it is still OK, Holds a 'meaty spanner, if that is anything to go by!,
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:05 pm
by Daggs
Could be an issue with the cut-out button. Remove it's green from the junction box and try again.
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:14 pm
by Martin20
Daggs wrote: ↑Mon Jul 30, 2018 5:05 pm
Could be an issue with the cut-out button. Remove it's green from the junction box and try again.
Series 3 Daggs, no cut out button!
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:24 pm
by Daggs
Well keyswitch then.
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:34 pm
by Adam_Winstone
Whether it be switch or button, the loom provides a green to kill the ignition to earth when you switch it off. For a standard 6v points model this is the double green from loom to junction box or rectifier, with one half of this double going off to the coil and the other to the headset (then to switch or button). If there is anything wrong in your loom or switches then you can find that this is killing your ignition (effectively having it turned off).
If you want to bypass this on a 6v system, simply extend your stator green to the coil terminal and try again. By bypassing the loom's dbl green green the ignition will always be ON.... but who cares as it'll allow you to then see if you have a spark at the bare HT lead end (holding it to earth, e.g. engine mount, bare metal rear strut bolt, other). If you then have a spark you'll know that your problem is not with stator, coil or HT, allowing you to then look elsewhere.
Good luck.
Adam
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:47 pm
by Martin20
Daggs wrote: ↑Mon Jul 30, 2018 5:24 pm
Well keyswitch then.
Re: Taking it to the tip, unless....
Posted: Mon Jul 30, 2018 5:49 pm
by Martin20
Adam_Winstone wrote: ↑Mon Jul 30, 2018 5:34 pm
Whether it be switch or button, the loom provides a green to kill the ignition to earth when you switch it off. For a standard 6v points model this is the double green from loom to junction box or rectifier, with one half of this double going off to the coil and the other to the headset (then to switch or button). If there is anything wrong in your loom or switches then you can find that this is killing your ignition (effectively having it turned off).
If you want to bypass this on a 6v system, simply extend your stator green to the coil terminal and try again. By bypassing the loom's dbl green green the ignition will always be ON.... but who cares as it'll allow you to then see if you have a spark at the bare HT lead end (holding it to earth, e.g. engine mount, bare metal rear strut bolt, other). If you then have a spark you'll know that your problem is not with stator, coil or HT, allowing you to then look elsewhere.
Good luck.
Adam
Cheers Adam, will give this a go in the morning.