• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

70 GTX ignition switch, relay, or starter motor?

Under Pressure

FBBO Gold Member
FBBO Gold Member
Local time
6:25 PM
Joined
Mar 31, 2019
Messages
716
Reaction score
2,266
Location
Michigan
Hi all, hope someone can give me some guidance on this,

- 1970 GTX 440/Auto
- New relay
- New battery
- New ignition switch in column
- New keyed ignition assembly (old was was peeling)
- New ballast resistor
Have power everywhere including to starter, but nothing when I turn the key to start and put in garage, worked fine this morning when i went for a ride.

Car does start/run if I get under it and jump the starter with the key on.
Can starter/solenoid go bad just like that?, its the only thing not new, all the rest of the parts I did last month and been working fine.

Idea's? possible things to try?

Thanks in advance, all input greatly appreciated
Bill
 
Could be the neutral safety switch. Run a jumper from the ground terminal on the starter relay to a good ground. That will remove the nss from the equation. If the starter works by jumping the two terminals on the starter, then it is fine.
 
ok, just went and tried jumper from ground on relay to good ground, no change,
I hate electrical, please keep em coming!
 
With all those new component, I’d guess a bad connection is likely, but who knows - any of these parts can fail at any time right out of the box.

You already tested the relay ground, so next, with the key in start position, the wire from the ignition switch should have 12v. If not, problem is somewhere between the relay and ignition switch (including the bulkhead).

If that passes, then I’d use a screwdriver to short the relay across the battery terminal and solenoid terminal. If the car starts it’s the relay.
 
Thank you all for you're valuable input, after trying everything you all advised on, I pulled off the harness from the neutral safety switch at the trans, it was pretty oily, I cleaned with contact cleaner, plugged back in and it cranked right up

I sure hope that was the gremlin and not just luck
All your help was very appreciated, Hope I can return the favor! (as long as not electrical, lol)
Bill
 
Sometimes my '68 fails to kick the starter over. I see where the ammeter drops voltage as if the starter is working.

The connectors on the starter relay are the first place I go. Slide off, slide on. Car starts.

A mechanic was doing some work on the car and it happened to him. He came running out all worried. I just explained that it was an anti-theft device. I went back, pushed on connectors that don't bolt on, and car started.
 
This is great to know, such a simple looking electrical system, but drives me crazy
Thanks for the heads up
Bill
 
Auto Transport Service
Back
Top