1986 ford f150

I have a 1986 ford f150 302, just changed battery and unintentionally cross neg and positive for split second. The truck didn't have any power at all, no dome light, radio, ignition. I changed the starter solenoid, still nothing. I found a wire burnt in half next to the solenoid, I corrected this and the lights immediately came on. Now when I start it it fires up for 2 seconds and immediately shuts off, I came hold the gas but still turns off immediately after it fires. I think possibly a relay is bad but not sure where to start. Any help will be greatly appreciated.

Reply to
gwmorris2
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You've popped the fusible links, at a minimum - check all fuses as well.

Reply to
clare

Are talking about fuse in the fuse box or the ones coming off the solenoid. Checked the ones under the drivers side dash all were good there, but I saw a few inline fuses too.

Reply to
gwmorris2

You have probably burned the fusible links. These are fuses in effect which look like wires including the one near the solenoid that you replaced. They have specific electrical qualities to function as a fuse. They must be replaced with like links of the same length to function as intended. Regular wire will not replace a fusible link. You truck has several of these all of which are required. When you are using the starter, the ignition is supplied thru the start circuit. When the switch is released to run, the ignition is supplied thru the run circuit. There are fusible links for the run circuit and the ECM as well as the fuel pump IIRC on that one. I do not recall the exact location of the fusible links. I believe they were all yellow in the harness on or near the left fender. Make sure you replace them with the correct links. You need to get hands on a vacuum and wiring manual for it which will give you all the info needed to quickly locate and test the circuits. It is probably still available from Helm, inc or can probably be found somewhere on ebay.

Lugnut

Reply to
lugnut

A quick check of the wiring diagrams shows that there may be as many as (depending on equipment) nine fusible links attached to the starter relay hot terminal.

You can't solely rely on a visual inspection, you need to pull on the fuse link to see if the outer jacket stretches, if it does, the wire inside has opened.

Also, since you've already swapped out the starter relay, make sure you didn't leave any fuse links disconnected or connected to the starter side of the relay versus the hot side. i.e., they should all connect to the relay post that the battery cable connects to.

Reply to
aarcuda69062

I am not sure if that year still had one but this sounds suspiciously like an open ballast resistor. Passes current with the key in start posn but when the key is moved to the run posn there is no juice to the coil.....

DaveD

Reply to
Dave D

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