1968 Car randomly dies

[Batgirl89]

Car starts & runs well. But randomly dies, like at stop lights or driving through intersections. Its very exciting. Usually dies many times when I have just started it and put it in gear. We changed the carb, but acts the same. I found some exposed wires on ignition switch today. Would this be the cause?? Also, the yellow wire looks alittle cooked. Black with green strip has been worn through. How do I repair or replace the ignition wiring? How would you proceed with this? As always, Thank you for your help, Sheryl

 

[Mosesatm]

Here you go.
https://www.cjponyparts.com/scott-drake-ignition-switch-wiring-pigtail-1968-1969/p/HW3125/

Installing it is loads of fun!!!

 

[Batgirl89]

Here you go.
https://www.cjponyparts.com/scott-drake-ignition-switch-wiring-pigtail-1968-1969/p/HW3125/

Installing it is loads of fun!!!

Thanks Arlie! ok so I do need change it (not repair wire with liquid electrical tape? :grin: )

How do I get the plug off the back? do I have to pull the ignition out?

 

[Mosesatm]

Thanks Arlie! ok so I do need change it (not repair wire with liquid electrical tape? :grin: )

How do I get the plug off the back? do I have to pull the ignition out?

The switch doesn't need to come out. There are two prongs on the connector that need to be pressed to remove the connector. One of the prongs is visible on the photo of the connector, there's another one on the other side.
All in all I think it's easier to remove the switch to gain extra room to work, using one of these tools.
https://www.cjponyparts.com/scott-drake-ignition-switch-bezel-tool-1967-1968/p/HW1661/

 

[Batgirl89]

The switch doesn't need to come out. There are two prongs on the connector that need to be pressed to remove the connector. One of the prongs is visible on the photo of the connector, there's another one on the other side.
All in all I think it's easier to remove the switch to gain extra room to work, using one of these tools.
https://www.cjponyparts.com/scott-drake-ignition-switch-bezel-tool-1967-1968/p/HW1661/

Thanks Arlie!
Do you think this is causing the random dying?

 

[Mosesatm]

Thanks Arlie!
Do you think this is causing the random dying?

I’m not sold on it yet. The others may want to chime in. A faulty coil can create the same issue, as can vapor lock.

 

[rvrtrash]

What Arlie said, plus check the wiring harness on top of the engine, and the pigtail from the distributor to the coil, as well. They get hot and the insulation breaks down, which can cause shorts. Check your vacuum lines and routing. If you have a factory tach, it might be going bad, which cuts out power to your coil.

Steve

 

[Batgirl89]

Thanks Guys! I did find a break in the insulation on the power lead(red with green strip) also the connection to the coil was shot, hardly any wire left to the connector. It show 11.8V at firewall connection & at coil connection with the ignition turned on. Ill drive the car now and see what happens

(this is the Highland Green car) Has Pertonix 2 with (45011) Flame thrower coil .6 ohms, Edelbrock carb 1403 500cfm electric choke, & AC

 

[Batgirl89]

Its 90 outside (too hot) But I need to see how the car is running.

Started & warmed up great. Put air cleaner on, died. Did this 2 more times. John saw black choke wire connector was hitting bottom of air clearner. Bends it down, air cleaner goes on, put in reverse then drive, no dying!!! (Always died reversing out) Drove 4 miles and it died. Starts right up, drive 1 more mile to dads, feel ignition switch and wires feels warm. At dads 5 mins, head home, live large I turn on the AC. Drive 1 mile, dies in same spot it died on the way over (crazy) Drive 1 more mile dies, ignition switch and wires at base very warm. Drive 3 miles dies. Starts right up each time and then I'm home.

Open hood. Coil and fuel line too hot to touch

fuel line is run on manifold. If you have vapor lock will the car start right up?

 

[rvrtrash]

Vapor lock means the gas in the fuel line gets so hot it vaporizes (no longer liquid), forming an air pocket that blocks fuel flow. It can change state back and forth as it cools and heats. I would think that the way the fuel line is routed under the valve cover lip, right on the manifold, would increase the possibility of vapor lock. It should have air flow around it and not be sitting right on hot metal.

Steve

 

[franklinair]

I agree with Steve. The fuel line should not be so close to the intake manifold. It should be re-routed to keep it as far away from the intake manifold as possible. I noticed the carb has a 'banjo' fitting for the fuel line connection so it can be rotated to any angle to accept the fuel line. (I usually rout the fuel line 3"-4" clear of the intake manifold.)

Not being familiar with your car's set up, all I can offer is an educated guess:
1.) I don't believe you're having a vapor lock problem (although I'm not comfortable with the fuel line routing).
2.) The fact that the engine starts right up, after shutting off leads me to believe there is a problem in the 'Run' circuit (pink resistor wire circuit that reduces voltage to the coil). When starting the engine, that circuit is bypassed, giving 12V to the coil + post.
When I install a Pertronix system I use a 'jumper' wire at one of the connectors at the firewall (adjacent to the left valve cover) in order to supply 12V to the coil when the Ignition Switch is in the Run position. This bypasses the Pink wire circuit completely.
Hope this helps without confusing you.

Neil

 

[Batgirl89]

Thank you Arlie, Steve, & Neil.
It does appear that the pertronix are installed on that "pink" line (I see it on the back of the ignition switch, but cant trace it) Neil do you recall which wire you tap into on the firewall ? (It has 1 tap for the electric choke so far) OR I found this relay during my research (this relay will correct the problem also right?):

 

[rvrtrash]

I looked it up on Pertronix's website, and it appears it's a solid state relay with a voltage regulator built into it. Exactly the way I would want to go. I would run a separate wire through the firewall and tap a switched source from the fuse block if I was installing it in my car. Less load on existing switches and wiring. Use a grommet of course so you don't see pretty lights coming from under your hood as you cruise down the road. :wink:

Steve

 

[franklinair]

Batgirl89;
Yes. The relay kit will work on your ignition system.
My way just uses a 4' jumper wire (25 cents instead of $32). It is virtually invisible.
I'll get a photo to show you, but it will be a few days to do it. I have my new garage scheduled for erection Thursday and 7,000 gallons of Avgas delivery, family reunion Friday, airshow & fly-in on Saturday, and reclusive REST on Sunday :icon_slee.

Neil

 

[p51]

I looked it up on Pertronix's website, and it appears it's a solid state relay with a voltage regulator built into it. Exactly the way I would want to go. I would run a separate wire through the firewall and tap a switched source from the fuse block if I was installing it in my car. Less load on existing switches and wiring. Use a grommet of course so you don't see pretty lights coming from under your hood as you cruise down the road. :wink:

Steve

Steve

Can you point me to where it states that it's a solid state relay with a voltage regulator built into it? I can't seem to find that info...

Thanks

Here is the info I found.
http://www.pertronix.com/prod/new/details.aspx?ID=138

... and the 'structions...
https://static.speedwaymotors.com/pdf/4472001.pdf

What I did was just use a standard Bosch automotive relay from the battery to the pertronix flamethrower (1.5ohm) coil and ignitor1. Basically set it up the same way it's shown in the pertronix installation instructions except with a Bosch relay.

Also, (another option?) I looked at the Shop Manual pages 19-36 and 19-37. It sure looks like signal 904 is a 12v non-resistor wire coming from the battery through the ignition switch and going to the voltage regulator. And it is hot during "cranking" and "run". If I'm reading the schematic correctly this might be an easily accessible 12v in the engine bay. However, I'm not sure whether this line should be loaded or not...

James

 

[Batgirl89]

Steve, Thank you!

Neil, You are a busy guy!!New garage is going to be wonderful!!
A picture when you have time would be great. (next week) Enjoy your Family, Sheryl

James, Thank you for the info, Ill look at my shop manual closer.

 

[rvrtrash]

Steve

Can you point me to where it states that it's a solid state relay with a voltage regulator built into it? I can't seem to find that info...

Thanks

Here is the info I found.
http://www.pertronix.com/prod/new/details.aspx?ID=138

... and the 'structions...
https://static.speedwaymotors.com/pdf/4472001.pdf

James

I did say "appears" because it doesn't come right out and say it, but it does, in my mind anyway, imply it. Here's why I believe it is.
First, it's a company that makes digital ignition systems and talks about increased accuracy in spark over "analog". With that background, it stands to reason their other products would be digital as well, and a "digital" power relay is a solid state device.
Second, the claim "Minimizes conducted voltage spikes by isolating the ignition power source from other high current equipment" implies a TVS type circuit, probably using a TVS or MOV diode.
Third, the claim "Provides consistent full battery voltage" implies a Zener diode or some other voltage regulation, otherwise voltage would change with RPM and load.
Fourth, with the control circuitry mentioned above, I don't believe you could put a reliable 30 amp magnetic coil relay in that size package. Taken all together, and reading in between the lines, to me, it APPEARS it's a solid state relay with a voltage regulator.
Of course I could be wrong and the actuall circuit uses something that looks like an old telegraph key, but without opening one up, I'll go with my first guess.

Steve

 

[p51]

I did say "appears" because it doesn't come right out and say it, but it does, in my mind anyway, imply it. Here's why I believe it is.
First, it's a company that makes digital ignition systems and talks about increased accuracy in spark over "analog". With that background, it stands to reason their other products would be digital as well, and a "digital" power relay is a solid state device.
Second, the claim "Minimizes conducted voltage spikes by isolating the ignition power source from other high current equipment" implies a TVS type circuit, probably using a TVS or MOV diode.
Third, the claim "Provides consistent full battery voltage" implies a Zener diode or some other voltage regulation, otherwise voltage would change with RPM and load.
Fourth, with the control circuitry mentioned above, I don't believe you could put a reliable 30 amp magnetic coil relay in that size package. Taken all together, and reading in between the lines, to me, it APPEARS it's a solid state relay with a voltage regulator.
Of course I could be wrong and the actuall circuit uses something that looks like an old telegraph key, but without opening one up, I'll go with my first guess.

Steve

Got it. Thanks much.

James

 

[Batgirl89]

Progress Report:

1. Installed Pertronix relay (per their directions, see attached)
2. Installed new solid state voltage regulator (removed original one, was making "clicking" sounds)

90s outside. Went for test drive. (John is at work, so he cant save me if I break down, but I have a credit card and AAA card ready!!) Starts right up. Drove 10 miles to Costco with AC on 1/2 way there. Ran good (didn't die woohoo) At about 5 miles ignition wires feel a little warm (I have the ash tray & bracket out so I can reach my hand in while driving to feel temp of switch and wires)
Feeling hopeful car all fixed. Pop the hood check stuff. Relay hot, coil hot & burns my finger. Shop at Costco, and buy a fire extinguisher to keep in car. 30 mins later, start car, doesn't kick right over, but starts. Feeling ignition and wires all the way home, getting hot, reburn finger on hot ignition wire. make it home, shut off car. Re start car, takes 2 tries. starts. Pop hood, I already know coil is as hot as the block (thus my burnt finger) checking relay wires, purple wire really hot (its connected to the red/grn start/run ignition wire) but red/grn wire not hot. Red wire, black wire on coil from pertronix, in distributor are hot. Radiator cap leaking (will change cap out with new one)

1. I will call Pertronix tomorrow see what they say.
2. Thinking what James said hook run wire to fuse box or tap into different wire like Neil does and not use that damn Red/grn (pink resistant wire)
3. ? change coil
4. looking like I will have to change ignition pig tail, this one is getting damaged. or is too damaged and causing the problems.

On another note, I fixed the gear shifter selector light (rod was disconnected) pulled center console apart without breaking anything! Found a stash of walnuts in the console! Also changed out the original AM radio(string is broken, cant change channels) with a original AM radio I purchased that a guy added FM to. I got it installed, turned it on to test, and a AC/DC song was on! it was so great to sit there and listen to it in the car drinking my cold coconut water, after a long hot day. (yesterday was hotter than today, not a good day to work on cars, it was too hot, I need a car shop!) Just trying to figure out the knobs, they aren't working out, posts seem too short? doesn't make sense

Drove my Grey CS all over the place on Friday, 50 miles or more, car never gives me problems....

 

[p51]

(1) ...Relay hot, coil hot & burns my finger.
(2) ...Feeling ignition and wires all the way home, getting hot, reburn finger on hot ignition wire. make it home, shut off car
(3) ...checking relay wires, purple wire really hot (its connected to the red/grn start/run ignition wire) but red/grn wire not hot.
(4) ...Red wire, black wire on coil from pertronix, in distributor are hot.

(5) 1. I will call Pertronix tomorrow see what they say.

#1. Not surprising that the coil is hot. It is drawing ~8A at ~12v ~= 100w... about what an incandescent, 100w light bulb would feel like. Add the background temp of a hot engine... ouch!

#2 This sounds dangerous. The current going through the ignition switch and out to the relay should now be significantly lower with the relay (eg ~0.2A with the relay vs ~8A without the relay). The red/grn resistor wire and the purple wire should not be much hotter than any other "normal" wires in a hot engine bay. (Caveat: the 0.2A number is what I calculated using a Bosch-style conventional electro-mechanical relay. I do not know the details of the Pertronix relay's internals).

#3. This is odd. The purple wire is hot but the red/grn wire which it is hooked to is not (?!?)... is this true at the point where they are connected?

#4. This doesn't sound surprising as the ignitor is switching the coil current. Having said that, I have never felt those wires after a long drive.

#5. Yep. A call to Pertronix sounds in order. The fact that the purple wire (and possibly the relay) is really hot while the red/grn wire is not is weird.