Testing HT leads with a multimeter - possible?

[Benjaminpalma]

I was just wondering whether I can test HT leads very precisely, using this method, rather than electrocuting myself with the engine running, and getting a does it/doesn't it answer.

Thoughts welcome...

[Zad]

You can set the meter to ohms and measure the resistance from one end of the lead to the other. What resistance to expect depends on the type of HT lead. It may be a simple copper wire (close to 0 ohms), it might be a resistive carbon wire (up to 50k Ohms) or a wire with a suppressor resistor in the cap (somewhere inbetween).

[bananapieface]

Really you would need to give them about 5 X operational voltage and check for leakage.

Best off replacing them every so often imho.

[buggalugs]

You can check the resistance end to end which will tell you if the bit in the middle has broken, it won't tell you if the insulation has failed and is earthing out somewhere when used in anger. You can sometimes see that if you watch them running in the dark though.

[Pumaracing]

Unless there's an actual break in the lead then probably not. The quoted resistance might well measure spot on but the insulation might have still broken down meaning they'll short out in use. Easier to swap for a new set.

[Benjaminpalma]

Thanks for your thoughts, guys! Yes I hadn't thought about that last one regarding any insulation breakdown...

[rev-erend]

An easy way to check for an issue is just to have a look while the engine is running at night .. with no lights.

Any stray sparks .. ?

I'm sure it's not a great test but shows a serious problem if you have one.