1991 Ford F250 starter is no crank condition

The Motorcraft positive engagement starter motor is used on all engines except the 4.0L and 7.3L Diesel. The starter system also includes a starter (ignition) switch, relay, neutral start switch (A/T) or clutch interlock switch (M/T), battery and heavy circuit wiring.
When the ignition switch is turned to the START position, the starter relay is actuated through the starter control circuit. This connects the starter motor to battery, permitting current to flow through the grounded field coil, actuating a movable pole shoe. See Fig. 1 . The pole shoe forces the starter drive plunger lever to engage the starter and flywheel gears.

check the Starter Relay
4.9LOn right front fender panel.
5.0L & 5.8LOn right front fender panel.
7.5LOn right front fender panel.

would a bad starter relay cause my problem? when i turn the key the relay just makes a loud clunk noise. what does that mean?

is it the relay on the fender panel making the clunking noise ? or the actual starter motor ??

it is the relay on the inside passenger side fender, i tried jumping the terminals but it still just clunked... idk i been stuck in patterson for 3 days cuz this stupid thing so im desperate for info

I have the EXACT same problem.....did you ever figure yours out? Did you check if your motor may be seized?
I've tried everything that anyone has told me about fixing this problem and still cant get it...please, if you got yours going, HELP ME!

have you tried replacing the relay on the fender panel .. get a wrench on crankshaft pulley bolt to turn engine by hand to check if engine is jammed up ??

I turned the engine over in my truck the way you said already. The relay isn't the problem because if I arc across it with a screwdriver, I get the same "click" noise. Its something AFTER that.

Big donation to the site if you can solve this problem PDQ for me.

There is nothing AFTER the relay except the starter itself ..try checking the fusible link i have arrowed on the bottom diagram ? DESCRIPTION The Motorcraft positive engagement starter motor is used on all engines except the 4.0L and 7.3L Diesel. The starter system also includes a starter (ignition) switch, relay, neutral start switch (A/T) or clutch interlock switch (M/T), battery and heavy circuit wiring. When the ignition switch is turned to the START position, the starter relay is actuated through the starter control circuit. This connects the starter motor to battery, permitting current to flow through the grounded field coil, actuating a movable pole shoe. See Fig. 1 . The pole shoe forces the starter drive plunger lever to engage the starter and flywheel gears.

so, thats good....are you stumped yet?

OK so you are getting power (hot)all the way through the system .. so we must have a bad ground ... we need to check ALL grounds I would start with the relay ground point on the fender wall ...then the starter ground.. see arrows on diagram .. let me know

all look top notch to me...

even it they LOOK good .. you will need to clean them off, to be sure of a good connection ?