electronic ignition... no spark

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HxPaul
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johnny650 wrote: Sat Dec 08, 2018 11:30 am
HxPaul wrote: Sat Dec 08, 2018 10:00 am
Daggs wrote: Sat Dec 08, 2018 9:18 am I'm glad you (seem) to have resolved the issue. But those magnets are usually fixed with epoxy glue and a screw, for very good reason.
Plus you have now moved them closer to all the coils, running a risk of fouling. You could have just gently bent the fingers up, they will take a gentle tweak.
I would have simply adjusted the pick-up position!
+1 Also you didn't put any loctite on the threads of the screws,so when the card get squashed over time (as it certainly will)The screws will come undone
The screws were loktited I just didn't show it in the video like I didn't show a lot of things.

Why not show a little appreciation for a useful tip for the Lambretta community instead of constantly finding reasons to critisise.
All I have to go on is the video,if you omit to add something how am I supposed to know that it should be there.I wasn't having a"go"at you,I thought that I was giving you a good tip,but apparently not.
Steveshipley
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just read this thread start to finish. well done Johny650 for sticking with it. I personally have never had this issue but when (and it will) does manifest itself I'll know what to do. also thanks to all the knowledgeable contributors. Great thread 👍👍
johnny650
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thank you Steve. It certainly has been a long trial.
I'm sure that if you buy a complete electronic kit from one supplier that all the components would work well with each other but I could only afford to buy cheap single parts from various suppliers and had some problems,
Who would have thought that moving the pickup closer to the magnets by just 1.5mm would make the difference between having no spark and having a strong consistant spark. A painful lesson learnt.
johnny650
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Adam_Winstone wrote: Sat Dec 08, 2018 2:06 pm

P
One thing that I've come across a number of times recently is the splaying of laminates on aftermarket stator bases, where the laminates splay and cause the face of the pickup to angle away from the flywheel face, with the top trigger moving quite a distance back from the flywheel. Its a shame as this is just a poor quality of manufacture issue, whereas even old original points stators have a rock solid laminate core after decades.

Anyway, well done for getting it sorted as a I'm sure that many of us have been sharing your frustration with this, having suffered similar in the past.

Cheers
yes good point to raise Adam I came across this myself last week but didn't get around to posting it as a warning.
The image shows laminate lift on one of my Stators . It doesn't look like a lot but it has a significant effect on the pickup gap and angle. It wasn't the cause of my no spark issue though, as this was corrected before fitting and testing.

I share your frustration with poor component quality control and materials. There is scarcely anything I buy for my vehicles these days that doesn't require some degree of fettling before being suitable for use.
Image
https://i130.photobucket.com/albums/p26 ... obqhlw.jpg
Adam_Winstone
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^
... that photo is very similar to a number that I've come across, with one just coming to me to sort out a misfire. The pickup and LT coil actually both read ok but both low figures, as is typical of the Indian aftermarket items, so I took the opportunity to swap both items out and rectify the angle issue at the same time. The owner was perfectly happy to spend the money on better quality upgrade items as he simply wanted to cure the misfire and end up with the reliable ignition that he should have had from the new stator from day one!

I really don't like these splaying laminate cores, which IMO should not have gotten through quality control.
johnny650
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Adam_Winstone wrote: Fri Dec 14, 2018 10:08 am ^
... that photo is very similar to a number that I've come across, with one just coming to me to sort out a misfire. The pickup and LT coil actually both read ok but both low figures, as is typical of the Indian aftermarket items, so I took the opportunity to swap both items out and rectify the angle issue at the same time. The owner was perfectly happy to spend the money on better quality upgrade items as he simply wanted to cure the misfire and end up with the reliable ignition that he should have had from the new stator from day one!

I really don't like these splaying laminate cores, which IMO should not have gotten through quality control.
Agreed ...its a terrible design, As you say the pickups ohm-out ok but the increased gap starts to cause erratic triggering and eventually no spark .
As my little experiment shows , all it takes is less than 1.5mm increased pickup gap to completely prevent a spark being produced.

With the amount of heat the stator is subjected to, its bound to result in expanded laminates . Who knows how many electronic ignitions have failed over the years for just this fault alone and not been correctly diagnosed . Frustrated owners deciding to just replace stators and flywheels and CDIs etc until they eventually get a spark .

One of these days someone will put all these little issues into a comprehensive troubleshooting guide or flow chart to help novices properly diagnose systems and components instead of just being forced to resort to replacing everything until it works again.


This issue reminds me of 'plate lift' on cars where the protective steel plates that the brake pads sit on gradually lift away from the aluminium calipers due to oxidation which eventually prevents the brake pads from returning sufficiently.
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