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Distributor to Spark Plug lead wire continuity

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Lin

Lin

Jedi Knight
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Hi guys,Educate me. When doing some preventative maintenance, I pulled a spark plug lead out of the distributor cap (using a 123 distributor) the cable pulled away from the terminal - not a particularly unusual outcome. Got a new 90 degree terminal and crimped it on to the cable (Pertronix cable) and before I put the boot on the end of the cable I thought I would check the continuity. It barely dropped below 1.


So then I checked a brand new, never used, cable made-up by AH Spares. As shown in the image below when the sensors are attached to each end of the cable I get a reading of .792 which is not sufficient to even sound the beeper on the multimeter device. I suppose there are degrees of continuity (not just on/off) but I guess I expected the alarm to sound and the reading to drop to near zero.


Could someone interpret these findings for me?


Thanks, as always.


Lin
IMG_0608.jpg
 
HI Lin:

Here is my interpretation :

The first reading of 1 is close to I Ohm

The second reading of . 792 is also close to 1 Ohm

Consequently either cable will work , but no 2 may be the best of the two-- Cheers
 
I tried zooming in to see which meter you are using but couldn't tell. Based on similar models, it looks like you have the knob turned to continuity (buzz) and diode check. The continuity function is not going to buzz until your resistance is below about 40 Ohms (according to Exectech product manual... see link below). The diode reading is going to give you a voltage drop value, not a resistance value.

Turn the meter knob to measure 20M Ohm and repeat your measurements. Then turn the meter down to the next lower settings sequentially (200k then 20k). The reading at 20k should give you an indication of whether your plug wires are OK. Resistor plug wires may be anywhere from 5k Ohm to 20k Ohm depending on length and construction. Solid core wires should show a resistance very close to zero Ohms regardless of length.

The link below is to a meter similar to what I see in your picture.
https://www.instrumart.com/assets/MN35-manual.pdf
 
Yeah Doug , that may help him out--
 
Those AH Spares bumblebee wires with the solid plastic terminals are not very good anyway. I bought some but quickly changed them out. Wires are OK but I hated the terminals.
 
DerekJ said:
Those AH Spares bumblebee wires with the solid plastic terminals are not very good anyway. I bought some but quickly changed them out. Wires are OK but I hated the terminals.
Click to expand...

Yeah:

I use the Bosch connectors and American made high performance stranded copper wire.
 
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