Buick RIVIERA 1993 Manual page 76

Engine Block Heater (Option)
In very cold weather, 0 F
(-
18 C)
or colder, the engine
block heater can help. You'll get easier starting and
better fuel economy during engine warm-up.
To use the block heater:
I. Turn off the engine.
L.
Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 110-volt outlet.
A
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a fire. You could be seriously injured.
Plug the cord into
a
properly grounded
three-prong 110-volt outlet. If the cord won't
reach, use a heavy-duty three-prong extension
cord rated for at least 15 amps.
How long should you keep the block heater-plugged in?
The answer depends on the weather, the kind of oil you
have, and some other things. Instead of trying to list
everything here, we ask that you contact a Buick dealer
in the area where you'll be parking your vehicle. The
dealer can give you the best advice for that particular
area.
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