Contact Points Dwell Angle (Dwell) - TechoTest 138-E Manual Del Usuario

__________________________________________________________________________ TIMING LIGHT
4.3 -

Contact points dwell angle (DWELL)

The DWELL measurement is a parameter independent from the advance, this test can
thus be performed before or after the check of the ignition advance angle.
ATTENTION:
The measurement of the contact points dwell angle can be performed only on
cars equipped with traditional ignition.
•
Start the test the timing light being in the rest condition; 3 displays on the
instrument control board are on.
•
Take the engine at the RPM indicated by the manufacturer trying to maintain it as
stable as possible by reading the measurement on the timing light display.
•
Press the TESTS key (6) to switch the reading of the volt/peak volt to the DWELL
angle reading; the VOLT led (7) turns off while the DWELL led turns on, (5) and
indicates that the DWELL display has been enabled.
ATTENTION:
This instrument has been conceived so that the read value is a true one,
regardless of the cylinder number; no calculation is thus necessary.
•
Accelerate
In case the variation exceeds 3° check the distributor.
•
The DWELL test is usually performed on all of the cylinders of the tested engine.
Connect the induction clamp to each plug wire to have the DWELL of the
subsequent cylinder, following the ignition sequence.
•
After measuring the DWELL of the whole ignition cycle of the engine connect the
induction clamp to the plug wire of 1° cylinder.
OPERATING INSTRUCTIONS
several times to detect possible DWELL variations.
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