fully charged battery but car won't start

[Inflewnzer]

Hello Everybody,

My problem is with my 68 coupe deville, I have a fully powered battery but when i turn the ignition i get nothing not even a click, Ive tried jump start that didn't work.
All power is working but no ignition??  is it solenoid? Started motor? I'm Stumped your help would be much appreciated.

Cheers Ants.

[Steve Passmore]

That could be a whole host of things so you have to check each in turn.  First thing I would do is connect power directly to the starter bypassing everything. That should tell you if it's the starter or solenoid.

[Roadmaster75]

Try starting it in "neutral".

Sometimes neutral safety switches get sloppy and will not start in Park.
It's happened to me in gm cars over the years.
Mike

[TJ Hopland]

Other than no click everything else seems normal?   Normal buzzers, dash lights, gauges, and they go out or on when you turn the key to start?  If so then my first thought too is the shifter switch.   Try moving the shift lever to various positions especially wiggling around P and N.   Keep a foot on the brake just in case it does happen to start in one of the gears and be ready to shut it off quickly.   

Before trying to start turn the key on and shift to R and see if your backup lights come on.   If they do that is a good sign that your switch is mostly in tact.   If they don't work your switch could be completely disconnected or broken.    The switches are usually 2 or more parts, there is a body that handles the mounting and mechanical bits then there is a vacuum and electrical section.   The sections are not held together by much so I have seen them were things just fatigue and come apart. 

If that does not help then next place I would be looking is at the wiring down by the starter.   Its common to have issues down there due it is location close to the ground and usually near exhaust.   Often times when a starter is changed people don't do a good job installing all the shields and routing the wire the way it was originally so things get damaged.     There are 2 small terminals on the starter.  The one labeled I if you can see the label connects to the ignition coil.   With the key on (not starting) you should see 12v there.  Its possible for the car to work without this wire or if there isn't voltage there with the key on so I would not worry too much about this one.   The S terminal is the one that energizes the starter,  this one should go to 12v when you turn the key to start.

[35-709]

On the '73 there are 3 fusible links, all running from the starter 12 volt post --- one to the fuse box, another to the ignition switch, and the third to the headlight switch.  There are no doubt 2 or 3 on your '68 as well, these fusible links live in hell down there at the starter in the heat, greasy dirt, wind, etc.  Check to make sure they are all OK and not broken.  If needed, fusible link wire is available at your local auto parts store, 2 are 10 gauge, one is 14 gauge, if one needs replacing I would replace them all.  Be sure you use the same gauge fusible wire AND THE SAME LENGTH.  Length and gauge are important for the proper functioning of the fusible wire. 

Below is a picture of the fusible links I took out of my '73 --- amazingly enough they were still working. 

[35-709]

If the problem is in the neutral safety switch, you will often hear a very faint chime or bong when the key is turned to the start position.

The neutral safety switch can be bypassed by jumpering the two 12 gauge violet wires at the switch by unplugging those wires and using a 12 gauge wire with male spade terminals to connect the wires in the connector.  If that works you have found your problem.