SAAC Forum

The Cars => 1967 Shelby GT350/500 => Topic started by: charlie D on February 16, 2019, 01:34:46 PM

Title: One lead to starter solenoid?
Post by: charlie D on February 16, 2019, 01:34:46 PM
Continuing to work through some sloppy wiring that was done when a shop installed the MSD ignition system. Seems as though he took everything apart to get the tach to work before figuring out a tach adapter would do the trick. Anyway, following leads in the engine bay is when I had an alternator wire just fall off in my hand, no insulation left. I have ordered a replacement alternator harness. But this car got so jury rigged that I am really getting flummoxed. Attaching a picture of the starter solenoid. Only one lead on the front terminals. Mind you, it did crank and start. Anybody seen anything like this? Not sure if I should be messing with it or just let it be.
Title: Re: One lead to starter solenoid?
Post by: Corey Bowcutt on February 16, 2019, 02:03:30 PM
Charlie, I am relatively new to this so do not have a lot of experience but I had some strange wiring on my solenoid as well that I corrected.  It did not have the same missing wire you have but I thought I would share some pictures in hopes it helps.  I have a GT350 and I believe yours is a GT500 so might be different?  But it looks like a brown wire to the terminal you are missing.

BTW the picture of my solenoid is before I removed the "extra" red cable to the terminal block which bypassed the ammeter.
Title: Re: One lead to starter solenoid?
Post by: Bob Gaines on February 16, 2019, 02:08:02 PM
Quote from: charlie D on February 16, 2019, 01:34:46 PM
Continuing to work through some sloppy wiring that was done when a shop installed the MSD ignition system. Seems as though he took everything apart to get the tach to work before figuring out a tach adapter would do the trick. Anyway, following leads in the engine bay is when I had an alternator wire just fall off in my hand, no insulation left. I have ordered a replacement alternator harness. But this car got so jury rigged that I am really getting flummoxed. Attaching a picture of the starter solenoid. Only one lead on the front terminals. Mind you, it did crank and start. Anybody seen anything like this? Not sure if I should be messing with it or just let it be.
Yes you have some modified wiring there . It is hard to tell what is going on from the picture .I am not by my picture file however here is a link to a picture file that Branda has on their website. It is a good reference.  https://sep.yimg.com/ty/cdn/yhst-13525187779972/ammeter.pdf
Title: Re: One lead to starter solenoid?
Post by: charlie D on February 18, 2019, 12:28:10 PM
Thanks Corey and Bob. I would send a picture of the birds nest of butt connections under the dash, but suffice to say it is shameful. This car has had 3 modifications involving the electrical system: 1- a pair of driving lights I installed in the 60's/70's when we were doing TSD rallies; 2-a back up electric fuel pump; 3 the MSD electronic ignition with magnetic pick up distributor and CD box. The lights and fuel pump installs are clean with circuit breakers, relays, and switches. Why would the solenoid be bypassed? What is the purpose of one wire? I do see the brown wire that Corey mentioned and it has simply had the connector cut off and left to dangle. I always thought that the two front connections on the solenoid worked to energize the interior switch of the solenoid and thus the rest of the electrical circuits when the ignition switch was turned on and sent full power to the starter when the ignition switch was turned to "start". If the solenoid is no being fed a "trigger" signal, how is everything else supposed to work? I will keep digging. Any thoughts/ corrections appreciated.
Title: Re: One lead to starter solenoid?
Post by: Corey Bowcutt on February 18, 2019, 12:55:28 PM
Charlie,

If it helps you out I have a complete Ford wiring book I purchased from Jim Cowels (sp?) I believe off this forum.  It has all electrical wiring diagrams for all 1968 Fords.  They have great detail and are printed on 11' x 17" paper so are pretty big and easy to read.  I am not a real good electrical guy but I work with electrical engineers and when I have had issue I bring the catalog to work and they are able to pour over the diagrams and help me find solutions.  I believe you live very close to me so if you want to borrow it you certainly can.

Corey
Title: Re: One lead to starter solenoid?
Post by: charlie D on February 20, 2019, 06:37:29 AM
Corey, thanks for the offer. I am working with the 1967 Ford passenger car repairs manual and the schematics in that book. I will PM you if I need more detail.
Title: Re: One lead to starter solenoid?
Post by: kjspeed on February 20, 2019, 09:40:33 AM
The missing lead is for temporarily sending a full 12 volts to the coil in cars with breaker points. Once the engine fires the coil is supplied a reduced voltage through a resistor wire or ballast resistor.
Title: Re: One lead to starter solenoid?
Post by: charlie D on February 21, 2019, 09:39:56 AM
Thanks KJSPEED. That along with the MSD installation instructions make perfect sense.