18 cs-57
- dave16mct
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Re: 18 cs-57
It sounds like a classic case of magneto condensor breakdown. When hot and it won't start remove the sparkplug and test for a spark. If no spark it's the condensor breaking down. You can get an Easycap Condensor which fits behind the points. The original condensor needs to be disconnected and insulated. Full instructions come with the Easycap. If there is a spark but the plug is very white then it's running very weak and this can make it very hard to start when hot.
Dave
Dave
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Re: 18 cs-57
Am presuming you have a Lucas NR1 or NC1 magneto on a '57 CS?
A common suspect would be the condenser, but maybe the HT winding. Both can cause the 'won't start hot' problem, with the condenser being the more likely - perhaps. Have you checked for a spark when it's hot?
If the magneto hasn't been looked at for a long time, maybe the time has come for an overhaul . . .
Dave just beat me on the keyboard . . .
A common suspect would be the condenser, but maybe the HT winding. Both can cause the 'won't start hot' problem, with the condenser being the more likely - perhaps. Have you checked for a spark when it's hot?
If the magneto hasn't been looked at for a long time, maybe the time has come for an overhaul . . .
Dave just beat me on the keyboard . . .
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Re: 18 cs-57
Thanks for reply.Wich Easycap do I need for the racing magneto?
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Re: 18 cs-57
If the contact breaker is as originally fitted, with a brass backplate, then it would need an EasyCap C01 (the standard fitment for an anti-clockwise driven Lucas magneto with a camring). If by chance the magneto has been fitted with the later steel backed contact breaker (they interchange), then it would be a C04. You can see pictures of both, and others besides, here: https://library.brightsparkmagnetos.com ... /index.htm (to be sure you are looking at the right thing).
You would need to extract or disable the existing condenser though, which is a bit of work.
RB Magnet, there in Sweden, may have the condensers in stock, and could probably help with any other aspects of the magneto that might need attention.
Good luck!
You would need to extract or disable the existing condenser though, which is a bit of work.
RB Magnet, there in Sweden, may have the condensers in stock, and could probably help with any other aspects of the magneto that might need attention.
Good luck!
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Re: 18 cs-57
EasyCap has worked well for me but on an SR1 mag.
Johnny B
Johnny B
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Re: 18 cs-57
OK.I think I will try easy cap.
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Re: 18 cs-57
Before you do it, you might like to read the booklet in the attached link if you haven't already, which explains what has to be done for the initial installation on a rotating coil magneto like yours.
It's relatively straightforward on a static coil instrument like Johnny B's SR1, but it's harder on N1s and similar with their original condenser buried in the armature. Subsequent condenser replacement is a two minute job (which is the whole point), but the first time is more complicated and will require some time, tools and patience.
https://library.brightsparkmagnetos.com ... ooklet.pdf
It's relatively straightforward on a static coil instrument like Johnny B's SR1, but it's harder on N1s and similar with their original condenser buried in the armature. Subsequent condenser replacement is a two minute job (which is the whole point), but the first time is more complicated and will require some time, tools and patience.
https://library.brightsparkmagnetos.com ... ooklet.pdf
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Re: 18 cs-57
Possibly a worn throttle slide/carb body. Will it start if you bump start it or if someone holds their hand over the inlet or, if fitted you close the choke ?