Depends on the fuel pump. Capacitor quenched units used until 1977, diode
quenched thereafter. The former don't need to be switched, the latter do.
Original factory pumps will all be negative ground of course, but
after-market positive ground versions for earlier cars are also available.
The only safe way to switch them is to disconnect the diode and reconnect it
the other way round. Reversing the 12v and ground connections to the pump
and ending up with a 'live' pump body is not a good idea. You can tell the
difference between capacitor and diode quenched units by the end-cap
covering the points - the capacitor quenched has a stepped end-cap, the
diode quenched does not. Electronic pointless pumps are a much bigger
proposition to switch, but again it would not be a good idea simply to
switch the 12v and ground connections.
If switching polarity it is also a good idea to reverse the connections to
the coil, it will work either way but the original direction of current flow
does make a difference.
Electronic tachs will also need to be switched - by reversing the 12v and
ground connections *inside* the case. The direction of current flow through
the pickup will also need to be reversed.
PaulH.
----- Original Message -----
> Starter isn't affected. Fuel pump needs to be switched.
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