Unsatisfactory readings can be due to defective wiring or connections.
Ensure that all snap-connector joints and earth connections are in good
condition before proceeding to Test. No, 2.
If considered necessary, check the rectifier by substitution.
(1) Disconnect the three alternator output cables.
(2) Start the engine and set to run at approximately 3,000 r.p.m,
(3) Connect the one ohm load resistance in parallel with the ax. volt-
meter and check the voltage between the alternator output cables.
(4) Conclusions to be drawn from results of above tests:
Demagnetised rotor magnets indicated by all readings being low.
Short-circuited coil indicated by individual reading being low.
Open-circuited coil or coils indicated by zero reading(s),
Earthed coil or coils indicated by voltage reading between any output
cable and earth.
Alternator. Model RM15, with rotor, withdrawn (REC 728).
CONDENSER CHECK
When investigating a misfire, and where the condenser is suspect, the
use of an external condenser will prove if this component is defective,
Use a sound condenser with two crocodile clips attached.
Attach one clip to the low tension terminal on the distributor, the other
to a convenient earth position.
A short test, by running the engine, will indicate if the condenser is
defective.
In the case of Single Cylinder Models, remove contact breaker cover,
fit one clip to terminal for contact breaker pivot post, the other to earth.
CHECKING THE RECTIFIER
If a spare rectifier known to be in good condition is available, the
simplest check is that of substitution. (In this connection, Lucas rectifier
47132 is used with alternators 540, 210, 18 and 047, 534, while rectifier
47142 is used in conjunction with alternator 540, 210, 05.)
When a satisfactory substitute is not available, the rectifier is best
checked by removing it from the machine and bench testing it.
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