Testing The Ignition Circuit Of A Battery-Coil Ignition; Ignition Coils - Rothewald 10002567 Mode D'emploi

stump do not need to be removed for testing. You only need to
disconnect the battery and remove the generator cover in order
to test the commutator, rotor and stator. The commutator does
not have any grooves. There should be no engine oil or rainwater
in the alternator chamber (replace seals as required). Check the
stator windings for continuity at the relevant cable connections as
described above. Test the rotor windings directly between the two
copper tracks of the commutator (as described). A low resistance
must be measured (approx. 2 – 6 ohms). If it is approaching
zero, there is a short circuit, and if it is high, there is a break in the
winding. The resistance measured to earth, on the other hand,
must be infinite.

6.2 | Testing the ignition circuit of a battery-coil ignition

6.2.1 | Ignition coils

If ignition sparks are either weak or non-existent, start with a visual
inspection of the cable connections and spark plug. If thin, burned
looking streaks can be seen on the coil housing, these could be
current creepage paths caused by dirt or material fatigue of the
coil body. Old spark plugs should be replaced. To test the quality of
the ignition spark, in the case of contact ignition, remove a spark
plug cap from each ignition cable, hold the cable at a distance of
5 – 7 mm from the engine block (wear a glove), switch on the
ignition and follow the start procedure. The spark should jump
across this gap (the spark from a really good coil will jump 10 mm
or more). With an electronic ignition unit, the test just described
should be carried out with a spark tester to avoid the risk of
damage to the black box. A weak ignition spark may (especially
with older vehicles) be due to a voltage drop in the ignition circuit.
For safety reasons, testing the ignition coils in an electronic
ignition system should be left to a professional workshop to avoid
risk of damage to the black box.
In the case of contact ignition, proceed as follows: Select the 20 V
) measuring range on the multimeter. Detach the positive
DC (
and negative cables from the coil, hold the black test probe against
negative (lead to contact, contact position "closed") and the red
test probe against positive (from the kill switch). The measurable
voltage must be 12 V (apart from rare cases in which there are
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