16-03-2025, 07:00 PM
(15-03-2025, 07:01 PM)John Cornforth Wrote: You should be able to measure points resistance on the 200 Ohms full scale range. Check the meter first by shorting its two probes together. The live feed to the coil needs to be disconnected for this test. Measure from distributor LT terminal to distributor body first, then from distributor LT terminal to the engine block to check that the distributor body is properly earthed. With manual advance/retard distributors there is a moving joint, so contact can sometimes be unreliable unless a "pigtail" is added from distributor body to engine block.
If the points really were 0.05 Kilohms (50 Ohms) the primary current in the coil would only be 0.12 Amps, which doesn't tally with your 3.9 Amps reading. Out of curiosity, how did you measure the latter ?
With 6 volts supplied to the coil and distributor.
Using 200 OHMs scale from LT terminal to dist. body I am getting 58.
from the LT terminal on dist. to head stud I am getting 68.
With 20Amps selected (and test lead changed over). With points closed I hold one probe to fixed part and other to moving part. Reading zero until I open the points and then it reads 3.5.
From the above tests can it be ascertained where the fault lies?