Ignition leads?

[Rick Draper]

Can anyone help me as i have **** all idea on this and dont have access to another one i can check. Should i be able to use a volt meter to check for current passing along a ignition lead as if i should the ones i have just made are **** lmfao.

[t45_ste]

To check for current you need a clip on ammeter. A volt meter is for checking volts. I also seem to remember that you shouldnt put a voltmeter on HT leads as it will blow the meter.

[Rick Draper]

Hmm still think i have done something wrong with them!

Although i cannot find any trace of current on just a piece of the lead so who knows....

[t45_ste]

ARe you testing the leads disconected off the car?

[MSG]

The answer is Nope you can't measuer current as the duration will be so brief that the meter will not even be able to sample the current spike going through it.

You can however check continuity, and most leads have a resitive chracteristics, which means they are no longer for centuries now use a copper conductor, it was disbanded centuries ago as it interfered with TV reception hence all ignition leads now use resitive conductor, so you should be able to measure the resitance of your leads from one end to the other, don't ask me how much it should be, I haven't a clue, but if you take a measurement of all your leads you will get what an avergae value should be. so compare all against each other, anyone showing unusually exteremely high resistance or just open circuit then thats your problem.

You said you made your own leads,, of course the other thing is the insulation coating on these leads is of a very high dielectric (insulation) and so any other wire with thick insulation simply will be no good, and as I said apart from the ends which are crimped you might find a short length of copper wire inserted only a few inches into the lead, and the rest of the wire consist of resitive conductor.....i.e. the wire is stuffed with some conductive material that has a resistive properties and is not a solid wire like if you know what I mean, thsi stops the radio frequency intereference.

I* think if I am not mistaken the resistance will be in order of a few Kilo Ohms.

[Rick Draper]

Thanks, the leads i have used have a carbon core with silicone insulation.

[MSG]

Oh right, so that is a proper material, but the ends have to be made by inserting a short piece of copper wire into the middle of the core, or like a thin spike inserted and then bent over and the brass terminal crimped over the end sandwitching this thin wire.

What kind of problems are you having with your leads, is the spark not reaching out, did you insert the wire at each end for termination????

[Rick Draper]

I need to go and buy some copper wire....

[leesturbo]

leads have high resistance rick which is fook all for the high voltage to get over so dont think there knackered cus the ohms arn't like a piece of cable

[joe joe]

the simplest way to check that you have spark is by sticking in a screw driver and getting it near something earthed on the body(i'm presuming you didn't know that)
to actually check the conditon of the leads, you should check how much resistance is between each end of the lead(you'll find the specs in a workshop manual)
if the car is running but you just want to check that it's all in good condition use a spark tester, for a car with coilpack it should at least be reaching 30kv, if its 28, 29 that is still considered no good(the coil pack is starting to break down)
for cars will old style dissy's you need it to reach at least 20kv