1990 HONDA ACCORD WON'T TURN OVER TO START BUT IT WILL ROLL START. I HAVE CHANGED THE ALTERNATOR AND TESTED THE IGNITION SWITCH STARTER RELAY SEEMS FINE CLUTCH SWITCH SEEMS FINE MAIN RELAY IS FINE

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Did you disconnect the battery recently?
Did you check for Diagnostic Trouble Codes?

Park neutral safety switch maybe be the reason for the no crank ! Try putting the vehicle in park ,then try to crank the engine . Testing the electrical circuit is the best way to trouble shoot this problem , along with do a voltage drop test on the starter circuit ! This will test the battery cables an connections .
Starter Voltage Drop
How to voltage drop test starter motor circuit
Does it have a manual or automatic transmission ? Manual ? clutch switch . Looking at a wiring diagram I also see a starter cut relay !
http://www.bbbind.com/free_tsb.html Free wiring diagrams . Enter vehicle info. year , make , model and engine size . Under system click engine , under subsystem click starting . Then click the search button , then click the blue link ! Check the starter cut relay also . Videos on youtube showing how to test a relay controlled circuit !

Your tempermental starting problem could be the park neutral safety switch . They get worn inside an cause this type problem . Next time it won't start place gear selector into neutral an see if it starts then . The cooling running problem is probably the cooling fan timer module . From the diagram it's hard to say which side the A/C condenser fan is on. The A/C fan has blue with yellow stripe wire in the connector along with a black one . I would also suggest you have a qualified repair shop do a voltage drop test on the starting circuit .
How to voltage drop test starter motor circuit

Starter Voltage Drop These test's will find any starting circuit problem .

It sounds like a fault in the starter circuit. It could be a defective neutral safety switch, starter solenoid, or possible a defective ignition switch but I doubt it. Can you hear the starter solenoid??? I'm willing to bet the problem is either with starter relay, neutral safety switch, or starter solenoid.

If your positive that the battery is fully charged and has been load tested,, then your ignition switch may be bad, if the relay is clicking that would mean its getting juice, I would strongly suggest that you have the battery checked,, with all those new parts,, it all leads back to the battery not carrying the amps it needs , if the click is heard at the starter relay

i have two things that come to mind first of which is your neutral safety switch ...its located on the clutch pedal ..its to prevent the car from being started in gear it may not be working correctly and wont let power to the started when you turn the key...most likely the problem...the other thing if thats not it you may need to check the ignition switch...

Sounds like a bad starter selinoid or starter itself...

The first thing you need to do is stop wasting your money by replacing parts. Then get a volt-ohm meter and a test light to test the circuits between the battery, the alternator, the ignition switch, the starter relay and the voltage regulator. (a.k.a. Charging System Circuits)

To start, the "B+" or "BATT" terminal on the alternator (large black wire) MUST have a solid, direct connection to the battery. Check for the proper voltage here. Then, the red wire on the alternator at the "F2" terminal should be HOT at all times. If not, you probably still have a bad fuse link that you missed. The "F1" terminal on the alternator (Light Green wire) is known as your "FIELD" wire. It comes from the "IG" terminal at the voltage regulator. It should be hot any time the key is in the ON position. If not, your voltage regulator is not working or your ignition switch is not providing power to the regulator. Finally, The "F" terminal (Red wire) at the regulator should be hot any time the ignition switch is in the ON position. This actually gets it's power from the starter relay, which gets its power from the ignition switch.

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