Purple Wire, No Start/Crank

[GEMELLI]

While I've been out of town for a few days, I spent several hours looking at all kinds of threads on this subject, but in the spirit of technical ideas, I'm starting a new one, hopefully without dead links and missing pictures.

I think we all know that if it's not one thing, it's another with these things. Now that I tentatively have the not running under boost situation handled, it seems like my purple starter wire has given up on me.

For the first time in several months, after replacing the vacuum lines and checking and rechecking every single electrical connection under the hood and near the computer, I finally got my Ty to boost in my shop. However, after letting it warm up a bit, and shutting it off, it wouldn't restart.

The battery is fully charged, and all the accessories have power to them, but the starter won't engage or even spin freely. If I repeatedly turn the key to start, I can hear a faint click. I did hold the key on start once, for a few seconds, but I could smell the short under the hood, so I obviously didn't do that again. I will replace the purple wire based off the info I've read, but I'd like to know what others have done. Ford starter relay? Heavier gauge silicone wire? Let's talk about what works and what doesn't work so good. Post up links, pictures, or anything else that could help me or anyone else in the future.

When I get back tomorrow, I'll get it taken care of. Thank you for any input!

 

[Jimmy]

Re: Purple Wire, No Start/Crank

While I've been out of town for a few days, I spent the several hours looking at all kinds of threads on this subject, but in the spirit of technical ideas, I'm starting a new one, hopefully without dead links and missing pictures.

I think we all know that if it's not one thing, it's another with these things. Now that I tentatively have the not running under boost situation handled, it seems like my purple starter wire has given up on me.

For the first time in several months, after replacing the vacuum lines and checking and rechecking every single electrical connection under the hood and near the computer, I finally got my Ty to boost in my shop. However, after letting it warm up a bit, and shutting it off, it wouldn't restart.

The battery is fully charged, and all the accessories have power to them, but the starter won't engage or even spin freely. If I repeatedly turn the key to start, I can hear a faint click. I did hold the key on start once, for a few seconds, but I could smell the short under the hood, so I obviously didn't do that again. I will replace the purple wire based off the info I've read, but I'd like to know what others have done. Ford starter relay? Heavier gauge silicone wire? Let's talk about what works and what doesn't work so good. Post up links, pictures, or anything else that could help me or anyone else in the future.

When I get back tomorrow, I'll get it taken care of. Thank you for any input!

Replace the purple wire from the loom above the brake booster (it's the thickest purple wire) with some 10 gauge wire to the solinoid.

I did that like 12 years ago ,no problems starting since.

 

[Throws]

Re: Purple Wire, No Start/Crank

Matching the gauge of the wire (purple wire in bundle over brake booster) should do the trick. I think if you ran some silicone wire similar to what an RC car would use (multi stranded as well) you would gain some heat resistance and current capacity (since RC cars can draw over 100A depending on motor/ESC used). Throw in some high temp loom and better routing... A++.

Also: Ditch the stock starter if you haven't yet. Go with the high-torque out of a '98 K3500 with a 454. Badass starter and it weighs a fraction of the old one.

-P

 

[aasltmike]

Re: Purple Wire, No Start/Crank

Matching the gauge of the wire (purple wire in bundle over brake booster) should do the trick. I think if you ran some silicone wire similar to what an RC car would use (multi stranded as well) you would gain some heat resistance and current capacity (since RC cars can draw over 100A depending on motor/ESC used). Throw in some high temp loom and better routing... A++.

Also: Ditch the stock starter if you haven't yet. Go with the high-torque out of a '98 K3500 with a 454. Badass starter and it weighs a fraction of the old one.

-P

x2 on the mini-starter. That's one of the first things I changed on mine when I got my truck and started tinkering with it.

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Replace the purple wire from the loom above the brake booster (it's the thickest purple wire) with some 10 gauge wire to the solinoid.

I did that like 12 years ago ,no problems starting since.

Exactly what I wanted to read. Thanks Jimmy!

I think if you ran some silicone wire similar to what an RC car would use...

Also: Ditch the stock starter if you haven't yet. Go with the high-torque out of a '98 K3500 with a 454. Badass starter and it weighs a fraction of the old one.

-P

I will look for silicone wire for sure, but at least I will protect it from the heat and route it in a way that will prevent physical damage. I will also replace the starter. From what I've read, that almost seems like preventative maintenance.

x2 on the mini-starter. That's one of the first things I changed on mine when I got my truck and started tinkering with it.

Thank you for the advice!

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Anyone with undead links or pictures for future reference? I'll take a few pictures of replacing the purple wire as I do it.

Is the general consensus to remove the prop shaft to better access the stock starter for removal?

 

[Don W.]

Re: Purple Wire, No Start/Crank

Prop shaft and starter are on opposite sides. No help there. As I've ranted before there is, IMHO, a correct and incorrect way to do the Ford starter solenoid mod. FWIW I still have my original wiring to the starter but with carefully configured heat shielding. Heat is the big culprit here. If your purple wire is toast then the re-wire from above the booster is the fix. Then add lots of heat shield down by the starter.

BTW the starter removal is no problem if you take a moment to remove the alum TC cover. 4 bolts.

Since these pics I've added some additional shielding to the wires that pass through the silver colored shield you see to the left in the pics. Even with all this there evidence of excess heat on the exposed end of the wire at the starter. I've considered adding a full starter shield but haven't done it yet.

My setup:

 

[SYCLONE#1531]

Re: Purple Wire, No Start/Crank

I added a remote starter solonoid to mine when I replaced the purple wire!! This really helps!!!

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Prop shaft and starter are on opposite sides. No help there.

I guess it's been a while since I was under the front of my truck.

Thanks for the great pictures, both of you. I had to order the purple wire in 10awg, so I haven't fixed it yet. I'll take a look at the starter tomorrow and see if the wire is bad, but I think I'll replace it regardless. At that point, I'll make a decision on the additional relay. I know that the wire in question is the largest of the three purple wires in the loom, but here's a picture of one of the smaller ones that appears to have some sort of electrical tape around it. Is that stock? Also, how far down does the starter wire come out of the loom? Once it's cut at both ends, can it just be pulled through from one end or the other?

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Well, after fighting the starter for about half an hour, I dropped the front of the prop shaft and the torque converter cover and it came right out. Just in case, I had the starter checked and it works perfect, so it's going back in tomorrow. I also got all my stuff together to replace the purple wire, except for the heat cover. Are you guys just splicing into the purple wire above the booster and running the new wire down to the starter outside the factory loom?

 

[SYCLONE#1531]

Re: Purple Wire, No Start/Crank

Yes, I spliced mine at or around the booster.

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

But then did you just run the new wire down to the starter or did you somehow get it into the loom? I don't want to clutter things up under the hood, but I also don't want cut into the harness loom if it isn't necessary. My plan was to hide the new wire behind the harness near the fire wall, then route it away from heat sources once it would be out of sight.

 

[Throws]

Re: Purple Wire, No Start/Crank

But then did you just run the new wire down to the starter or did you somehow get it into the loom? I don't want to clutter things up under the hood, but I also don't want cut into the harness loom if it isn't necessary. My plan was to hide the new wire behind the harness near the fire wall, then route it away from heat sources once it would be out of sight.

I routed mine in it's own corrugated tubing, keeping it away from heat sources.

-P

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Exactly what I wanted to know and hear. Thank you very much!

 

[GEMELLI]

Re: Purple Wire, No Start/Crank

Ok, I got it handled and it worked like a charm. I didn't end up replacing the starter because it's brand new and I didn't want wait for another one to be delivered. Thank you for all your help!

 

[turbo7521]

Re: Purple Wire, No Start/Crank

Do you just pick a random spot on the purple wire to splice into it or replacethe hole thing out of the harness?

 

[Don W.]

Re: Purple Wire, No Start/Crank

Any spot that's back from the burnt section should work. The trick IMHO is to keep the heat away down at the starter with shielding, high temp wire covers and keeping the wires tucked back as far from the exhaust as possible. Here's my setup, still using the stock wire with 3" DP. Even with this setup that last little exposed piece shows that it's been pretty warm.