Finally put the car back together after 1 job turned into 10!
Started by replacing dizzy with Valencia jobbie, this meant stripping the wiring loom back to remove ballast resistor, had to remove dash to get at
wires, so thought might as well re-cover it, looked crap, so decided to make another. Then rest of interior looked tatty, so thought might as well
replace carpets. Then boot lid looked tatty so made a new one. Anyhoo, back to the point, I ain't got no spark from new dizzy. Wiring seems ok,
but coil was one I had lying around (12v, before you ask). What resistance should coil windings be? Mine measured 3.5 ohms from centre contact to
each terminal.
If I turn dizzy just past a trigger point, the coil -ve terminal dips by less than half a volt, surely not enough to give a spark?
I would value your opinions.
Marcus
The dwell time should be in the order of miliseconds, dwell time is the time when the contacts or the mcu puts the gnd to the coil after releasing the
gnd from the coil it sparks,
sow you could easyly test the coil.
altough its a very bad test because an small error in the coil can easy rise the dwell time wich will result in bad sparking//sparks...
3,5ohm sounds high, but the problem is that multimeters will difer much in such low ohm readings...
hope this is enough stuff to take your conclusions
Tks
Shouldn't you have 12v at coil plus and 0v at coil neg (ground) with the points closed and at the trigger point the coil negative goes open
circuit? i.e. no longer grounded.
[Edited on 17/4/06 by Dusty]
is it an electronic coil?points ones wont work,is dizzy body earthed when you spin it?
thats the way it works...
should work..
put coil on negative initiate dwell time, when you will take away the negative again the spark will come!
on beamer si know we measure 1,5ohm coil resistance and its in series with a huge 1 ohm resistance
Tks
Conrod, you may have hit the nail on the head there! Coil I used was Bosch 12v - didn't realise an electronic one was different!
Always assumed coil negative was taken to earth by points, not open circuited. If it went o/c, surely you'd get no transformer action, no induced
current so no spark?
Marcus
bills in the post marcus (not my dog bill by the way)
How did you wire up the distributor? STR the Wallage book may be showing an error when wiring the valencia unit
Just been reading this - http://www.locustenthusiastsclub.fsnet.co.uk/knowlegebase/elec_ign/electronic%20ignition..htm
Seems to say a standard 12v coil will do.
Wiring - Green coil -ve, Black coil +ve, Brown chassis. How complicated could it be!
Think I'll go and have a play
Marcus
Standard 12v electronic coil will do, best to get the one that goes with the distributor. We put a wrong one on a Granada and blew it up 
.
There's a lot of oil and wire inside them when they go and it makes a right mess
Marcus, wiring sounds right, if correct type coil doesn't work you may have a faulty ignition module . Usual fault with electronic distributors.
Thanks for all the replies, now anyone know of a locost source of Valencia coils?
Burtons want 40 quid plus vat!!!
Marcus
Cheers Jason, just bought it
Marcus
Allways glad to help a friend of Bob's
Jason
Quick update on the spark fromt - STILL GOT NONE!!!
Actually not strictly true, replaced the dizzy again for the standard points jobbie and it started first click!
Beginning to think I've got a duff electronic module. Anyone out there in Locost land know where to get these and roughly how much?
If it's fairly dear, I'll wait till the winter and go Megajolt.
Marcus
Another update:
WE HAVE SUCCESS!!
New ignition module and the thing fired up first time. Just have to retrieve my timing light and I'm off again.
Roll on Newark!
Nice one !