Dumb question about coil lead from dizzy

[Fingolfin]

The thick one that comes from the upper-center of the distributor cap. I've seen various terminology for it, but didn't know which was right.

Anyway, the problem is this: I've been trying to hook up the lead to the coil (it's in the dizzy cap quite well) and haven't had any luck. It's the earlier type of coil with the little terminals marked SW and CB rather than + and -, and the bakelite acorn nut that holds in the thick lead.
The reason I haven't had any luck is, I feed the lead through the acorn nut, and slip one of the washers over the exposed wire (which is fuzzy rather than copper, like fiber optic wire; dunno what's with that), and then feed it into the back of the coil and screw up the nut (all per Workshop Manual section C.3.2) -- and the lead pulls right out, with practically no force, from the back of the coil.

Is it supposed to not be held in very well? Anybody know what's going on? I feel like this is something that should be obvious.

[mike.perry]

I assume that you are using copper core cable.
Trim the outer sleeve exposing about1/8" copper core. Slide acorn over and twist wires tightly together. Slide washer over core and splay wires. Fit in coil and tighten acorn. Note that the threads on the acorns vary in length so check that you have the correct size.

[Fingolfin]

So far as I can tell, it's not a copper core wire. The exposed end is fuzzy, like so...[frame][/frame]

[kennatt]

its the later carbon fibre core,there is a metal cup affair which has a central bit that goes up inside the core and then wraps round the outer and is held by the insulation ,this then all pushes into the end of the cap and holds in place,this type then usually has a rubber cup which pushes over the dome on the dizzy /coil to hold it in. . The copper core leads, Called an HT lead in uk (High tension) is much better but causes radio interference hence the later carbon fibre ones.

[bmcecosse]

As above - that is the infamous 'carbon string' lead. Either change it to copper core, or make some sort of adapter from copper wire to hold the thing in......

[Fingolfin]

Hmm. Well, I think I'm more interested in having the coil lead stay put than preventing radio interference -- and if I myself ever want to fit a radio in Mog, I can fit a suppressor! I'll change it to the copper core.

[mike.perry]

Radio interference was a problem with the old AM systems, I don't that it affects FM or digital reception.

[Fingolfin]

I believe I have found a solution to my problem. I went to a local motor shop and obtained a new cable, which was still 'carbon string' but had this fitting on the end, which I modified slightly (the bent-up tine):[frame][/frame]
The tine was low enough to pass into the socket in the coil without any trouble, and the metal part butts nicely against the metal inside that socket. But the tine is high enough that it wholly prevents the cable from dropping out of the coil:[frame][/frame]And, in fact, it's such a good fit that the cable doesn't even wiggle.
Now all I have to do is insert it into the dizzy cap, which I think should be easy enough -- just baring the end and tightening the screw. Does anyone see any problem with this setup? I thank all of you for your help!

[kennatt]

thats the bit I was trying to describe

[bmcecosse]

That's the idea...... For the experts out there - can anyone tell me why carbon string does not cause wireless interference and copper cable apparently does ?? I'm guessing it;s to do with resistance of the cable........even then - how does it work??

[beero]

"can anyone tell me why carbon string does not cause wireless interference and copper cable apparently does ?? "

It's just voodoo magic!

[bmcecosse]

Oooooooooohhhhh right - best not ask then......

[kennatt]

I think its because the strings are shielded with an insulator then placed inside the rubber cable.You can see it on the photo

[bmcecosse]

Can't be that.. they would need to be shielded with an earthed metallic shroud (Faraday's cage) to have any hope of anything like that working......

[lambrettalad]

that Faraday has a lot to answer for

It's electricity Jim but not as we know it

I think it's the Lithium crystals in the coils hyper-drive captain

[Fingolfin]

Dilithium -- lithium is a whole different element! I believe it's down to the opposite of the Faraday cage effect -- electricity passing through a metal creates a powerful electromagnetic field, potentially affecting radios, while electricity passing through carbon, silicon, or other semiconductors doesn't make such a potent field.

[kennatt]

beam me out of this thread scotty too technical

[bmcecosse]

It's NEVER the 'coils' Jim .......