Starter wires?!?!?

[Rad Tad]

I have a 90 K-5 with a tbi 350. I just replaced the engine with the help of a couple of friends. The problem is that they removed the starter and don't remember how the wires go back on. There are 2 large wires from the positive batt. terminal and 3 small wires that come down the heat sheild from on top. I know one of the small ones goes to the sensor right above the starter, but I'm lost on the others. The starter has one large and one small terminal on the solenoid. I have tried figuring the wires out myself, but the starter engages every time I hook the battery up (with the key off). HELP!!! This is my daily driver and if I can't get it running I have to rent a car to go to a wedding this Saturday!

 

[Jagged]

Generally... the big wires go to the big terminal... and the small wires to the small terminal

 

[pauly383]

You have the wires on wrong . Not too sure of the color on your year , in years prior it was purple to the solenoid trip . The others go on the other small one . The purple ( or whatever color yours is ) by itself goes on the small one that trips the solenoid .

 

[Rad Tad]

I guess I could be more descriptive. The 2 sets of wires (large & small) each have one large and one small cable terminal. The 2 from the batt are plain black (big end) and black with a red stripe(little end). The 2 from on top are purple (little end) and red with an inline fusible link (big end). I tried matching terminal end size to the posts and it tried to start when I hooked the batt up. I know the 2 from the batt are pos and I think the red one is neg. I'm totally lost. I can go take pics and post them if it would help.
-Mike

 

[pauly383]

I'll dig up a wiring diagram later when I am home . Or do a search on here , several members have wiring pics in thier signature links , try muddytaz .

 

[guido666]

Do you own a voltmeter? Hell, you could even use a 12v lightbulb with a couple wires. Test your big wires for 12v. Any that have 12v (between wire and negative battery terminal or ground) go on big terminal. IMPORTANT: AFTER, after, after you have connected those to the big terminal test again the remaining wires. Any that now have 12v positive also go on the big terminal. Repeat this until you have no wires remaining that have 12v. The rest go on the small terminal (it should only be 1 small wire really).

 

[Rad Tad]

I just tried putting all of the wires but one on the small terminal with the same results (starter engages). The engine has just been completely removed, stripped of its accesories, and a rebuilt put in its place. I could even have the wires in the wrong place. Does the truck draw its positive side through the starter? I know the large black wire goes to the starter because it has an "idiot proof" cable end on it, and the purple is to engage the solenoid, but I'm lost on the rest of it.

 

[guido666]

Yes, the truck draws all other positive through the starter.

It also usually has a mess of wires that aren't described in the wiring diagram exactly, that draw power from there too. Those are your extra wires you're having a problem with.

One of the wires should be dead (normally). It only gets positive when you hit the key. Test and find this wire. If you do as I explained before (assuming your key switch didn't go bad and stick ON), one of the wires without 12v should get 12v when you hit the key.

 

[mud390]

I'm in a similar boat, but my starter wire caught fire. Long story. Skip the boring stuff about fire and here is where I am now. Originally had 5 wires at the starter. Now I have 3. I have the purple wire, by itself, on the "activating" (don't know the real name) post, the positive battery cable on the large post along with the wire from the alternator. The other two wires that were also down there are now rewired as follows: The wire that provides power to the fuse box is wired straight to the battery with a 25 amp inline fuse. The second wire, which goes to the "distribution block" is wired straight to the battery with a 25 amp fuse as well. Its not quite complete as I ran out of day light, but I'll finish it tomorrow. Hope that helps.

Kris

 

[guido666]

The reason that the positive goes to the starter, and then everything else goes off the starter is that the starter isn't competing for power during cranking. With the positive wired straight to the battery, the starter and everything else fight over who gets power, which can lead to problems or slow starting.

Realistically, there should only be one wire going to the small terminal.

 

[frankin5]

the dark blue goes to the knock sensor. the red the splices to the pink fusable link got to the battery terminal on the starter as with the heavy cable from the battery. the purple wire goes to the small terminal. this the keyed starter wire. the battery cable has a second wire that goes to the large post on the back of the alternater.. just looked at my '90 tbi engine and wiring harness sitting in my gargage waiting for me to put in in my '85

 

[Rad Tad]

Got it. I could BS everybody, but I'll just admit that it was the battery lead to the alternator. The starter works, I just kinda bumped it, and came back into the house for more beer. I going back out to fire my new engine for the first time! Wish me luck! (Hopefully nothing else is in the wrong place....)

 

[guido666]