Ford Automobile User Manual page 144

3. Connect the negative (-) cable to the negative (-) terminal of the
assisting battery.
4. Make the final connection of the negative (-) cable. Make the
connection to an exposed metal part of the stalled vehicle's engine, away
from the battery and the carburetor/fuel injection system. Do not use
fuel lines, engine rocker covers or the intake manifold as grounding
points.
Do not connect the end of the second cable to the negative (-)
terminal of the battery to be jumped. A spark may cause an
explosion of the gases that surround the battery.
5. Ensure that the cables are clear of fan blades, belts, moving parts of
both engines, or any fuel delivery system parts.
Roadside emergencies
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