starting issue

[genthree]

73 with auto...

I have new starter relay, starter, pertronix, plugs and wires.  Up to recently, no issues at all.  Now when you turn the key, the starter will engage for a very short time, then nothing.  I replaced the starter and relay, I guess I need to replace the switch?  Short between the switch and relay?  If you turn the switch a couple time it will start and may work several times then it will quit working....  Any other suggestions???

 

[Bully Bob]

I think you're on the right track..,

Try turning the key to "on" & see if the gage needles flicker, or rise slightly.

Then when it tries to start then stops (let go of the key in the "on" position).., see if the needles start dropping.

If so.., the switch is likely worn.

However, the needles may not drop & just the "start" contacts are faulty.

The switch is pretty easy to change. Just be sure to disconnect the batt. first.

Note the correct wire connections upon un-plugging/plugging on the new switch.

P.S. Your info. shows a new wiring harness.., did it come with a new key-switch..?

 

[genthree]

The harness didn't come with a new switch, but I don't remember if I put a new one in or not. I will watch the gauges and see what they do. I know I put a new key tumbler in it but I don't think I did anything with the switch....

 

[Bully Bob]

I'm pretty sure my '66 has the orig. switch.

Rarely, after start, I notice the gages had dropped back to (or below) "0"

A slight tap on the dash & the gages jump back to life.

I haven't decided if it's the switch contacts or the ground at the gages.

(pretty sure it's the ground)

Hasn't done this for many months now...?

Yours would be the "run" contacts if, in fact, it's the switch.

 

[Bully Bob]

Also, There's a "start" circuit & a "run" circuit"  for the ignition.

You may just have a loose connection on the "run" portion.

One bronco I bought had a new wiring kit. I had to go thru & re-crimp some of the connectors

as they were pretty loose.

 

[genthree]

UPDATE:  After work went out to start it.  Did the same thing, starter engaged for a second then nothing.  Turned the key a couple of times, still nothing.  Then I notice smoke coming out from under hood....  

Pop hood and notice one of the wires from my neutral safety switch is melted.  Anyone ever heard of this??  Spliced around it and drove it home with no issues.  I supposed i could have had a short in my wiring to the NSS that was causing the intermittent start??    I will check continuity and OHM it to see what is up...

 

[Bully Bob]

I think ya found it..!!  An ya.., now the work begins, finding out what caused this.

The owner of WH4x4 took his just restored EB out for a test run.

It caught on fire & got "smoked" by a fire extinguisher.

Don't let this happen to you..!!  But, do carry a fire extinguisher 'til this issue is solved.