Starter Stays Engaged (my wiring is a mess, help me fix it)

[Scudly]

I have a 1965 Mustang with a 5.0 EFI. We did the wiring with a battery relocate to a storage box within the car and the starter solenoid is back there too. Last week I burnt up my starter due to the fact it was staying engaged, I replaced it this weekend but found out the issue was still persisting. I'll post 2 pictures and a diagram of how my wiring is and try my best to explain it ... and hopefully someone can help me fix it.

I do not have the 12 gauge wire to the starter like instructed in the diagram below yet, and I don't know which terminal to hook it up to... can someone help me out and get me to fix this mess :-/

 

[Scudly]

On the far left you can see that terminal that I think might be a ground... no idea.

My dad did most of the wiring

 

[stang&2Birds]

I can't find the link for the Ford mini-starter install instructions.

You have a common problem. That's because doing a one wire setup to a mini-starter MAY KINDA SORTA SEMI work. And, you get people that don't know any better telling others "that it works fine".


You must have two wires going to your mini starter. Have you heard of a little known car called the Prius? Well, it uses it's "starter" also as an alternator to slow the car down and recharge the batteries. A starter and an alternator are very similar. After the power is removed from the stater during cranking, the starter is generating power because it's still turning from kinetic energy! So, in a one wire setup, that generated voltage from the starter can go back and keep the solenoid latched on.


So, you need to do the following:

1) Battery wire to the big terminal on the starter relay. I'd strongly suggest a 150 amp fuse at the battery to prevent the battery from BLOWING UP if that main big wire gets shorted to ground. (Red wire in jricker's diagram).

2) Output wire from the solenoid goes to the smaller terminal on the starter relay. (Yellow wire in jricker's diagram).

 

[stang&2Birds]

On the far left you can see that terminal that I think might be a ground... no idea.

My dad did most of the wiring

FYI:
In the upper left, the short black battery cable goes to an isolated feed through. That's not a ground stud.

 

[Scudly]

2) Output wire from the solenoid goes to the smaller terminal on the starter relay. (Yellow wire in jricker's diagram).

Thanks for the reply, I figured I really needed that 2nd wire... but looking at my Solenoid I still don't know which part to hook it up too

 

[Scudly]

FYI:
In the upper left, the short black battery cable goes to an isolated feed through. That's not a ground stud.

Can you explain the isolated feed through?

 

[Scudly]

Was that the wiring diagram you were talking about btw?

 

[bgdowski]

May i suggest disconnecting your "starter wire" from your solenoid, turning the car to accessory (Right before the starter click) and seeing which posts are not hot via the use of a multimeter, then having a buddy switch it to start, and seeing which dead post is now hot... if it shows 12v, and you have a single wire starter... hook em up!


Im not very clear on the situation, but a multimeter is your best friend when it comes to wiring...

 

[Scudly]

I don't have a single wire starter though, I have one of the mini starters.

I probably could benefit from using the multimeter though...

I look at those other wiring diagrams and see one side of the solenoid has all the hot stuff going into the one side... and on mine I have something going off that I'm not sure of what it is. Guess I gotta talk to my father about how he wired it.

 

[bgdowski]

I know im a window-licker when it comes to explaining things, so i apologize in advance...


Im just going out on a whim here and assuming that your "mini starter" (which i have had zero experience with, btw) has two + wires running to it... one for power, and the other for a power signal. My ranger, pre-engine swap had a two wire starter that had a power wire (always hot, connected to the battery) and a signal wire that went to a post on the main solenoid. This was factory. When i went to a 5.0L, it went back to a single wire and all i did was run a fat wire from the solenoid to the starter, getting rid of that big wire thats aways hot between the starter and + battery terminal.

SO, basically what im trying to say is maybe the fat wire is "always hot" (connected to the battery directly) and your smaller wire is a signal wire that goes to the "Start" post on your solenoid... Make sense?

 

[Scudly]

Sounds right, I think I have it figured out, I just need to wait till Saturday to do it though... So Antsy to fix it.

It turns out that my dad did run a ground from the solenoid for some strange reason.

 

[Scudly]

Okay I do have that ground in the trunk, should the solenoid be connected to that ground?

Yes or no