71 died...just died!

[240 Tom]

Hi, I hope someone can give me some advice.

My 71 Z had been sitting in the garage for about a month due to the cold and snow so yesterday I decided to start it up for a quick spin around the neighborhood. Went to start it and it was stone dead...nothing, looked around and could't find any lights or anything else left on and thought it was strange, but I I got the jumpers and it started right up. I hopped in and started driving and everything was fine...but I did notice that the amp gauge was not showing a high rate of charge as I expected. I had the radio turned up and was just enjoying the drive.

I figured I would drive it for a while to get a charge back in the battery but after about 10 minutes the car suddenly and completely shut down, like I turned off the ignition. I got out the jumpers again and it started again, but before I could put it in gear it completely shut down again. I got out the jumpers a third time but this time I got nothing with the jumpers attached, not even a hint of the engine turning...just stone dead. I noticed that on my previous jumps I would get a tiny bit of normal sparks on the jumper clamps when attaching them to my battery while already attached to the other car, this time I was getting nothing, no sparks at all as if I was putting the two jumper ends on a wooden board with nothing completing the circuit.

When I bought this car last year I noticed that the power line for the aftermarket radio was simply looped under a fuse in the fusebox which meant the radio turned on even when the ignition was off, but now even the radio was stone dead which I assume to mean there is no power getting to the fusebox. I had it towed to a local garage and the mechanic checked it out and told me he found that the ignition switch socket to the harness was loose and that he wiggled it in and the car started right up. I wondering if this makes sense to anyone? The ignition cylinder is worn and hard to turn, but would it kill the power to the fusebox where the radio was wired into? Does anyone have any thoughts on this...I'd hate to drive it away only to get stuck somewhere else because the problem was not resolved. Is there anything else that could cause this kind of intermittent failure?

Thanks in advance for any help ~ Tom

Edited January 24, 2013 by 240 Tom

[EScanlon]

What your mechanic actually wiggled was the Ignition SWITCH BODY HALF itself and not the connector nor the metal part connected to the Ignition Lock. By wiggling the Bakelite half of the switch, he moved the electrical contacts mounted on it so that they then made contact with the contacts on the internal switch lever (connector) and then was able to start it. Remove the Switch from the Lock via the 2 screws that hold it attached and then see if the brown bakelite half can swivel with relation to the metal half. It should NOT rotate at all, but over the years the two will have lost their grip to each other and can then slip out of position. It is this rotation that is causing your contacts to be intermittent.

That the Ignition CYLINDER is hard to move is a function of the KEY LOCK and not of the Ignition SWITCH, although it is conceivable that the Switch is the reason for your cylinder to be having the mechanical resistance to turn. Once you have the switch off you can then determine if the cylinder needs servicing (lubrication) or locksmith attention. Don't use WD-40 here, check with Unkle (another board member) for what he recommends, but WD-40 will only be a momentary fix that can leave you with more problems later. I've used Graphite Oil, but have heard that Locksmiths have better lubricants.

Replace the Ignition SWITCH. This is a fairly common failure amongst these 40ish old cars, and often the source of a lot of electrical gremlins that defy normal / standard diagnosing. Once you do that you can then diagnose accurately if the problem lies elsewhere.

Use Occam's Razor for diagnosing/ fixing these cars... find the SIMPLEST explanation that covers the facts rather than the most complex. More often than not, that will get you going again.

FWIW

E

[240 Tom]

Thanks so much for the advice and I will follow your recommendations on checking the ignition switch.

I still question if a faulty ignition switch could cause loss of power to everything else such as the headlights and power to the fusebox. As I mentioned, when the car died I lost power to everything. Thinking about it now, even when I had the jumpers attached on my third try I was still not getting power to the headlights and as I mentioned the radio that was wired directly to the fusebox also shut down. Can a faulty ignition switch case this? If not, does anyone have any suggestions as to what might?

Thanks again ~ Tom

[SteveJ]

Without quantitative results with a voltmeter, no. You may wish to inspect your grounding points in the engine bay, though.