I had a starter go out last year,so I replaced the starter and solonoid. Since then, When I go to start the car,I get a click sometimes before it starts. Just replaced the solonoid with a new one and still get the same results. Have tried different shims but still get a click (sometimes). Any ideas???

Is the engine hot when the problem occurs ?

When I go to start the car,I get a click sometimes before it starts
Does it start, or just click? If it makes a click, and then starts, I would think the problem is in the brushes in the starter, or a bad connection to the brushes. The initial 'click' is the solenoid energizing. You could still have a problem with the +batt. cable, and ign. switch prob., a corroded bulkhead conn., etc. It has to have a full +12v to crank. Make sure your cables are in good shape, and the con. tight @ batt. & starter. Make sure that when you replaced the solenoid that you got the small 5/15" bolt from the sol. to the tab/connection on the end of the starter tight. That is the +12v to actually spin the starter motor. Some replacement solenoids have a short post for this that requires a 'spacer', and some have a long post to begin with. Supposedly, the long post is for the 'high torque' starters, due to the longer field windings on the armature. You can interchange the starters, but sometimes you might have a problem with them, depending on the reman quality. Hope this helps some. I'm sure Ken can give more info on how to check the voltages @ starter.

First see if you can tell just what is clicking.  It could be a relay or the starter itself.

You want to check the battery voltage when it does this. If the voltage only drops a few tenths of a volt when it clicks and does not start, the solenoid is probably kicking, but the starter not turning.  Fi the is the case you can check the stud from the solenoid to the starter and see if you have power there when it clicks.  If so, the starter motor is not functioning, but the solenoid is.  If not, the solenoid is not working.  This assumming the click is the solenoid. 

If the click in not the solenoid check the purple wire going to the small terminal on the solenoid.  If it has power when the key is turned to start but the solenoid does not fucntion, then the solenoid is bad.  If there is no power to the purple wire the wire, neutral safety, or ignition switch is the problem.

This is all provided you have the correct battery voltage to the batt cable connection at the starter.  Put your positive lead of the volt meter at  the starter battery connection.  Negative to a good ground.  (are you SURE it's a good ground) You should read battery voltage, and when it's cranking it will drop a couple of volts.  If it drops several volts see if it does the same thing at the battery.  If so, the battery is failing, if not the cable or connection is bad.

While you are down there, check the starter ground.  Place the volt meter positive lead on the starter housing, and the neg on the battery neg.  Crank the engine.  It should read 0.  If not you have bad ground connections.

Do a few checks, locate the click, and let me know.

Thank's for the imput guy's. First off, The starter and solonoid were new last year,new battery,new ign. switch. Just replaced the solonoid with a Standard Blue streak ($46). Only clicks once out of three or four starts.(hot or cold) Thinking maybe a bad neutral safety switch. Is there a way to check this or is it adjustable? Will keep ya posted. All cables look good.

If the solenoid itself is clicking, the neutral safety switch is okay.  If the neutral switch is bad, the solenoid won't click.

If the solenoid is clicking, either it's bad, the starter is bad, or you have a poor connection.

Found my problem. Turned out to be a bad ground connection. Thank's for all the imput.

Good news!