Porsche 911 TURBO - 1975 WORSHOP, Manual

Page: 219 / 252

Practical Tips, Minor Repairs
219
f Carefully ensure that conductive jewellery
(rings, chains, watch straps) does not come
into contact with live parts of the vehicle.
Danger of caustic burns.
f
Do not lean over the battery.
Danger of gas explosion.
f Keep sources of ignition away from the
battery, e.g. naked flame, burning cigarettes
or sparks due to cable contact.
f
Before connecting jump leads, it is essential to
thaw out a frozen battery.
Connecting jump leads
Always observe the sequence below:
1. Connect the positive lead (red) to the
positive terminal of the discharged battery
first, then connect it to the positive terminal of
the donor battery.
2. First connect the
negative cable (black)
to
the negative terminal of the donor battery, then
connect it to a suitable grounding point on the
vehicle with the discharged battery.
This grounding point must lie as far as possible
from the battery.
For example, a solid metal part or the engine
block are suitable grounding points.
If no suitable grounding points are to be found
on either vehicle, the negative lead must
carefully be connected directly to the negative
terminal of the battery.
If a suitable grounding point is to be found only
on the donor vehicle, the negative lead must
first be connected to the terminal of the
discharged battery, then to the grounding point
of the donor vehicle.
3. Run the engine of the donor vehicle at a higher
speed.
4. Start the engine.
An attempted start using jump leads should
not last more than 15 seconds. Then allow a
waiting period of at least one minute.
5. Note
Before disconnecting the jump leads, electrical
loads such as the heated rear window and the
heating fan blower should be switched on (the
vehicle's lights must not be switched on). This
reduces voltage peaks which may occur when
disconnecting the jump leads.
With the engine running, remove both jump
leads in reverse order.