I bought this truck, a 98 f-150 last month and it came with an electrical issue. Parasitic drain. I’ve been going from one thing to the next trying to identify and fix the problem. I’ve replaced the alternator and battery, most of the fuses, o2 sensors, fuel pump, fuel filter it had other issues as well, battery cables, ignition switch, lock cylinder. I’ve taken a multimeter to the battery and checked the fuses for a draw and the draw indicated something with the ignition system. Also, the door alarm goes off when the drivers door is open without the key in the ignition. As I said I’ve replaced the ignition switch and lock cylinder but still get door dinging when it is opened. I checked the starter itself and the leads were rusted and corroded so i decided to replace. Here are the basic steps I would do if I had to change it ever again;
1. Disconnect battery cables and replace if corroded or have exposed wire
2. Jack the truck up and remove the passenger tire and wheel well
3. separate the exhaust pipe from the exhaust manifold
4. remove the exhaust manifold. Mine was cracked in two pieces and had to be replaced anyway but made removing the starter so much easier.
5. Remove the positive and negative lines to the starter solenoid
6. using 1/2 in socket and extension, remove the bolts holding the starter in place.
7. Install new starter (I would spend the extra money and get a brand new one from a reputable company. I’m just saying….this isn’t something I want to be doing again for some time)
8. Scrape and clean the engine block with a putty knife, install new gasket and manifold and reconnect to exhaust pipe.
9. reinstall wheel well and wheel. Lower and clean up and hook the battery back up

 

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