1985 FORD F150 LARIAT,, WON'T START

1985 technology is pretty simple, so just do diagnostics. Got to be fuel, spark, compression, or a defect in the starting system if the engine will not even turn over. Maybe that forty year old starter switch finally gave out. Or maybe it's that original fuel filter.

So you see spark at the plugs, you can see the accelerator pump squirt fuel into the Venturi, so how is the compression? Have you checked the cam timing to make sure it hasn’t jumped time?

STEVE ROSS HERE, YES ,, I HAVE CHECK THE COMPRESSION,, NUMBER PISTION IS AT 191 POUNDS AND NUMBER 5 IS AT 91 POUNDS. I DID NOT CHECK THE REST. THAT WOULD NOT BE WHY IT IS NOT RUNNING ,,,,RIGHT?? stevgwee@sbcglobal.net,,, 1985 ford f150 lariat with a 351w

STEVE ROSS HERE AGAIN, I GOT A SPARK PLUG TESTER AND I TURN THE KEY ON TO CHECK THE SPARK FROM THE COIL TO THE DISTRIBUTOR AND NO SPARK. REPLACED COIL TWICE. LAST THURSDAY IT RAN FOR ABOUT 10 TO 15 SECONDS AND AFTER THAT NO RUN. STILL TRYING TO WORK IT OUT. DO YOU KNOW WHY? THE TIMIMG IS OK ,, WHEN I BRING THE NUMBER PISTION UP ALL THE WAY TO THE TOP THE ROTOR IS POINTING ABOUT 12:00 RIGHT AT NUMBER ONE SPARK PLUG WIRE. CAN YOU HELP ME? stevgwee@sbcglobal.net

I think there is something wrong with the site. I have tried to respond but it won't take my reply from my ipad so I'm trying my PC.

Okay that works but now I don't see any of the other responses.

So if you don't have any spark now even with the new coil the cause could be a bad distributor pickup coil or ignition module, as you stated you had replaced the module and distributor, if it was a remanufactured distributor chances are very high that the pickup coil is the problem cause they don't replace them during a rebuild.

Do a dry and then a wet compression test on all cylinders, they need at least 110 lbs dry for the engine to run properly but it will run with somewhat less but not the best.