The starter on a 1990 Ford F-150 Motor lorry has a solenoid attached directly to the starter. The solenoid is the actuator for the starter. It further has a bendix, which is a straight tooth gear on a spiral shaft used to mesh with the bell gear on the flexplate and rotate the engine. When competency is applied to the solenoid, faculty is directed down to the starter Engine. As the Engine begins to spin, the bendix rotates up the shaft due to centrifugal impact and meshes with the flexplate.
Instructions
1. Buck the elementary terminal with power--using the jumper wire--to Everyone of the terminals that did not demonstrate capacity. The starter should impel when these terminals are jumped. Whether the starter does not propel, either the extensive calibre battery (+) wire is corroded and broken, or the bantam wire from the ignition is broken or came off. Remove the jumper wires. Assign the voltmeter's nigrous first place onto the bad terminal and the bittersweet cause on the confident terminal. The battery should include 12 to 12.75 volts. Whether the battery is under 10.5 volts, charge the battery and retest.
2. Examine the fuse in the fuse and relay box on the Chauffeur's side fenderwell. Stare at the lid on the box: there should be an illustration that Testament denote the residence of the starter fuse and relay. Whether the fuse is blown, alternate it and retry the starter.
3. Pull the starter relay away of the box. You Testament look four female terminals. Corner the voltmeter's ebon head on a acceptable ground and advantage the blood bulge to probe all four terminals, looking for force on one wire. Commemorate this terminal. Acquire an assistant turn the ignition solution to the flying start position. Probe the remaining three terminals for competency while the switch is in the open position. Go back Everyone terminal and direct your helper to Proceeds the ignition switch and turn it off. Provided there is no potential with the switch in the originate position, the ignition switch is evil.
4. Evaluation the battery for Disinfected, tight connections. Provided the connections are loose, tighten them with a wrench. Whether they are corroded, appropriateness a imperceptible bathe and baking soda to remove the corrosion. Avail a voltmeter to analysis the battery's voltage. Whether the starter works but does not turn the engine over, either the bendix is worn out, or the gear teeth are worn off the flexplate. This happens when someone consistently holds the ignition switch in the start position after the engine is started.
5. Raise the truck with a floor jack and support it on jack stands placed under the frame. Check for power at the starter end of the battery (+) wire using the voltmeter. Place the black lead on a good ground and probe the large wire terminal on the solenoid. If no power is present, replace the battery (+) wire. If there is power and the small wire is also connected to the starter solenoid, replace the starter. Check the battery ground cable from the battery negative to ground for a solid clean connection.
6. Remove the bolts around the cover at the bottom of the torque converter with a socket. If your F-150 does not have a cover, the starter will need to be removed to see the bendix. Assuming there is a cover and the starter turns but does not turn the engine, have a helper turn the key to the start position. Watch to see if the bendix comes out and engages the flexplate. If it does not come out, the bendix is bad, requiring replacement of the starter. If the bendix comes out and tries to engage the flexplate, the ring gear on the flexplate is bad, and the transmission needs to be removed to replace it.
7. Disconnect the negative terminal on the battery with a socket. Remove the two bolts in the starter with the socket and pull the starter out of its hole in the bell housing enough to see inside the bell housing. Look at the teeth on the flexplate. If the teeth are worn, it needs to be replaced. If not, the starter needs to be replaced.
