Cadillac: 1990 Brougham starting problem, cadillac brougham, starter solenoid

Question
Hi Tom, thanks for being here.
I have a 1990 Cadillac Brougham that I can't start.      It first occured three days ago.  I turned the switch to start it but there was no response.  After checking all I could do (in a parking lot)I tried rapping on the starter/solenoid and lo and behold it started.  I was able to start it normally the next morning three times but the fourth time it wouldn't crank.  I checked the voltage of my 7 year old battery 12.7 volts, 9.6 or greater under load.  I checked the wiring to starter and found I had approx  12 v olts at both battery terminal and ignition switch terminal (while key in start position).
I removed starter and bench tested it; it would not run.  I replaced starter/solenoid (bench tested okay)but still doesn't start.  The solenoid  does not click when I turn the key to start position.  I have checked the fusible links that    I found behind the battery distribution terminal and all are okay.  I have checked the fuse box and I see nothing wrong there either.  I read about a relay but where might I find it and how do I check it.  The only other thing I can think of is ignition cylinder.  Obviously I must be missing something,right?   Any advice would be appreciated.  

Answer
I can e-mail you an electrical schematic of the starter system.

You will need to contact me at:


 onlineautohelp@msn.com


In order for me to provide you with pictures, Instructions and electrical schematics (pictures).

PLEASE include your original question(s) and the MAKE-MODEL-YEAR and ENGINE SIZE of your vehicle when you contact me.

PLEASE tell me if you do your own repairs and or your skill level of auto repair. This is VERY VERY important if I am to be able to help you repair your own vehicle.