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D 150 no spark

Posted:
Fri Jul 28, 2023 3:50 pm
by tonytoolbox
Hi,i have a model D that has lost its spark , it has a Howard chambers 12v conversion ,i have change the plug ,cap ,lead ,cdi ,checked the earths and tested stator plate with multi meter
the readings from the stator are as they should be on any 12v lammy stator ,i havnt taken off the flywheel yet to look at the stator up close as the readings are ok
is there anything ive missed in the process of elimination as still have no spark
im not to familiar with the shafter, but as an owner would like to maintain it
thanks in advance
Tony
Re: D 150 no spark

Posted:
Fri Jul 28, 2023 11:51 pm
by Thackers
Hi Tony.
I'm not sure how the D has the engine cut off, switch or button etc but i would give that a look. Carbon deposit or dirt contaminating the switch making it earthed so no spark. Could be a wire or plate loose inside the "switch" also
Re: D 150 no spark

Posted:
Sat Jul 29, 2023 4:01 pm
by tonytoolbox
hi Thackers
yh i had already eliminated the green wire for the cut
i have now tested the voltage produced when kicking over and im only getting between 20 and 30volts as opposed to 50volts min
think i may need new stator?
havnt got much hair left
really appreciate your input
thanks Tony
Re: D 150 no spark

Posted:
Sat Jul 29, 2023 8:05 pm
by Thackers
Chances are the black box pick up has gone then. I had this happen on my home made 12v conversion Cometa . They're cheap enough to try first before changing out the complete stator.
Unless the woodruff key has sheared and the timing is way out.
Re: D 150 no spark

Posted:
Mon Jul 31, 2023 9:48 am
by Rob Miller
I also have one of Howards 12V conversions on my 150D. I found the quality of the stator he supplied was poor and it soon failed so I fitted a BGM stator which has given me years of good sparks. Its also important to know that the flywheels were re magnetised to reverse the polarity of the magnets because the flywheel turns the opposite way to later machines.
Re: D 150 no spark

Posted:
Mon Jul 31, 2023 4:29 pm
by tonytoolbox
hi Thankers
once again thanks for your views on my issue ,will probably swap out my stator
Rob, thanks for your input , my stator is also not the best looking ,i do have a bgm stator on my shelf so will use
also when you say the flywheel is reverse polarity i take it this has been done by Howard? was there any issue with fitment of the bgm other than elongating the bolt holes of the
stator and rewiring using the original stator loom as its longer
many thanks again
Tony
Re: D 150 no spark

Posted:
Mon Jul 31, 2023 5:04 pm
by Rob Miller
Yes Howard did the remagnetising. He would use a compass to check the polarity before and after. He was my first port of call for shaft drive parts and advice. I didn't need to put longer wires on my stator. The main issue I found with an ignition that doesn't retard at kickstart speeds is that the kickstart kept trying to break my foot.
I solved this by fitting a Kytronic advance box which does the retarding.
Re: D 150 no spark

Posted:
Mon Jul 31, 2023 10:05 pm
by tonytoolbox
hi Rob
kytronic advance box looks complicated with all those settings and possibly something else to go wrong
will see how i get on with stator plate swap out and if i dont break my foot
thanks again
Tony
Re: D 150 no spark

Posted:
Wed Aug 02, 2023 12:35 am
by jbcollier
Last no spark Lammy I worked on had sheared the flywheel hub. Not common and obvious if you look for it.