no fuel in carbs

PostPost by: Uboat » Sat Nov 09, 2013 10:17 am

.

So I believe that the gnition timing is way wrong, and will leave the carburator thread for now, thanks all!
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PostPost by: billwill » Sat Nov 09, 2013 10:59 am

Galwaylotus wrote:For static ignition timing I rigged up a light (12v bulb with cables and crocodile clips soldered to the two terminals). Connect one side to the earth side of the coil and the other to a good earth. Rotate the crank until the timing marks line up with 10?BTDC or whatever your spec is. Then rotate the distributor anticlockwise until the bulb lights (just). Clamp the distributor and you're ready to go.



Erm should that not be: Until the bulb just goes OUT. !
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PostPost by: Galwaylotus » Sat Nov 09, 2013 12:09 pm

Seems like it should but no; it's when the bulb lights. When connected as discussed and the points are closed, there are two paths to earth and the 5 ohm resistance in the bulb I'm using must be more than the resistance through the points path. When the points are closed, more current flows through the points circuit than the bulb so little or no light from the bulb. When the points open, all the current must then flow through the bulb and hence it lights! 8)
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PostPost by: oldelanman » Sat Nov 09, 2013 12:12 pm

billwill wrote:
Galwaylotus wrote:For static ignition timing I rigged up a light (12v bulb with cables and crocodile clips soldered to the two terminals). Connect one side to the earth side of the coil and the other to a good earth. Rotate the crank until the timing marks line up with 10?BTDC or whatever your spec is. Then rotate the distributor anticlockwise until the bulb lights (just). Clamp the distributor and you're ready to go.



Erm should that not be: Until the bulb just goes OUT. !


The bulb is wired in parallel with the points and so will light when the points open as the distributor is rotated clockwise.
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PostPost by: Galwaylotus » Sat Nov 09, 2013 12:34 pm

oldelanman wrote:
billwill wrote:
Galwaylotus wrote:For static ignition timing I rigged up a light (12v bulb with cables and crocodile clips soldered to the two terminals). Connect one side to the earth side of the coil and the other to a good earth. Rotate the crank until the timing marks line up with 10?BTDC or whatever your spec is. Then rotate the distributor anticlockwise until the bulb lights (just). Clamp the distributor and you're ready to go.



Erm should that not be: Until the bulb just goes OUT. !


The bulb is wired in parallel with the points and so will light when the points open as the distributor is rotated clockwise.

I knew I had a typo in there somewhere! Of course the distributor must be rotated clockwise as the advance comes against the normal operational rotation (anticlockwise in the Elan). Thanks for the correction oldelanman! :oops: :D
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PostPost by: billwill » Sat Nov 09, 2013 12:38 pm

billwill wrote:
Galwaylotus wrote:For static ignition timing I rigged up a light (12v bulb with cables and crocodile clips soldered to the two terminals). Connect one side to the earth side of the coil and the other to a good earth. Rotate the crank until the timing marks line up with 10?BTDC or whatever your spec is. Then rotate the distributor anticlockwise until the bulb lights (just). Clamp the distributor and you're ready to go.



Erm should that not be: Until the bulb just goes OUT. !


Galwaylotus wrote:Seems like it should but no; it's when the bulb lights. When connected as discussed and the points are closed, there are two paths to earth and the 5 ohm resistance in the bulb I'm using must be more than the resistance through the points path. When the points are closed, more current flows through the points circuit than the bulb so little or no light from the bulb. When the points open, all the current must then flow through the bulb and hence it lights! 8)


OOOps, sorry, you are right, the bulb will come ON when the points (or virtual points of a Centronix) open up, .
The setting required is the moment when the points open.

I had just realised that and was coming back here to modify my comment above, but you all beat me to it. My momentary lapse was because I used to do it the other way, removing the lead from the distributor and putting the bulb in series with the coil and the points. But the method described above is easier.
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PostPost by: Galwaylotus » Sat Nov 09, 2013 2:12 pm

I guess if you snooze you lose on this forum! :lol: :lol:
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