Thread: Another Pontiac for the firebird

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Here's the diagram download for American Autowire's Highway 15 system, and if you want the Highway 22 it's on their website, too.
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Highway15.pdf
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On my roadster, the GM one-wire alternator is connected direct to the positive battery post with a #10 stranded conductor, with a braided ground strap connecting the alternator case to the block, so it's "HOT" all the time.

I suggest you read this article from Mad Electrical

Catalog

Firebird, whether you choose/have the one wire or three wire alternator you'll find that the alternator output is to the battery, so it's hot along with those other things you noted (brake lights, cigarette lighter/power source, horn, dome light, flashers if you have them, etc, etc) which is what you asked.

My electronic flasher circuit controls brake lights also, so I'll have it hot. The alternator is a three wire. I think I've seen the article, thanks for linking it.

All the schematics I've looked at show the field winding (sense lead) hot, along with the indicator lamp, but I don't see the harm in putting them on the acc. Circuit.

I've got everything coming through the firewall landed on terminal strips, so next I'll be wiring in relays. I'm definitely thinking to put a relay between the start solenoid and the switch. Should make the ignition switch last indefinitely.

Originally Posted by firebird77clone

I've got everything coming through the firewall landed on terminal strips, so next I'll be wiring in relays. I'm definitely thinking to put a relay between the start solenoid and the switch. Should make the ignition switch last indefinitely.

Seems to me that the starter solenoid IS the relay to protect the ignition switch, and adding a relay in the circuit is an unnecessary complication and an added failure point with little value. Just my $0.02

R.S. I can't argue that point beyond that the ignition switch failed, so I'm torn.

Originally Posted by firebird77clone

R.S. I can't argue that point beyond that the ignition switch failed, so I'm torn.

Electrical components fail. Used to be that many could be taken apart and cleaned/repaired, but no so in this throw away society.
Adding a relay to protect a relay or switch is redundant unless you're dealing with a very high current situation which is not the case in your situation. Finding a quality replacement ignition switch is the challenge. NOS is your best bet.

Is it possible that the switch was OEM, making it ~80 years old?

Originally Posted by firebird77clone

My electronic flasher circuit controls brake lights also, so I'll have it hot. The alternator is a three wire. I think I've seen the article, thanks for linking it.

All the schematics I've looked at show the field winding (sense lead) hot, along with the indicator lamp, but I don't see the harm in putting them on the acc. Circuit.

I've got everything coming through the firewall landed on terminal strips, so next I'll be wiring in relays. I'm definitely thinking to put a relay between the start solenoid and the switch. Should make the ignition switch last indefinitely.

The flasher.. which one? 4 way "emergency" or the turn signals ? No matter, the brake light switch feeds the turn signal switch... so there is no control from the flasher. The accessory circuit will only be "live" when the key is turned into that position.... think that one through in regards to alternator! adding a relay to control a relay?? why?

Switch was not stock. I found one exactly like it, I think the generic ignition switch at O'Reillys was the same one.

The flasher unit is a little electronic box which accepts signal from brake light switch. It doesn't have a hazzard function. Maybe I should look into an upgrade.

Today was a wiring hiatus, I pulled the heater box. The stealership said the heater worked. Judging by the mouse nest, frozen temp valve, and 1/2" bolts used to block off the hoses; I'm guessing that was a lie.

I spent about an hour on ebay looking at heater cores, I picked something in brass that might work and ordered it, plus a brass cut off switch, an operator cable, and a hood latch cable. That reminds me, I need a wiper motor.

I found a kit for wiper install on a golf cart / 4 wheeler, with water bottle, nozzles, button, etc.. 50$. I'll let ya know if it works out!

The ol' girl has got tricks!

I decided to "hot wire" it and go for a ride, even though the dash is out. Besides, it gave me an opportunity to confirm the speedometer cable shaft was working. (It's not).

Anyway, the alternator wasn't charging! I double checked everything, and decided to back to O'Reilly to get checked, and it was ok. Turned out the terminals weren't mating in the plug. So, now for a ride. Nope, now it won't shut off! I was planning to use the disconnect switch in the floor to kill everything, but I had to pull ignition loose from the fuse strip. After a some dinking with it, I figured out that the disconnect only breaks the circuit if there is no load.

Strange.

I ordered a complete headlight switch from a 64 tempest. It took some grinding on the bezel with the Dremel tool, but it fits like factory. Now I'll have dimming dash lights, yay! I'll use the old headlight switch (75A rating) for the windshield wipers.

At work I chucked a button head bolt into the lathe and made a bezel for the led alternator light. It doesn't work, too long, so a couple flat washers will do the trick.

The craptastic starter switch practically fell apart when I torqued down the terminal nuts. I replaced it with the one from O'Reillys which looks similar but has a crimped ring to hold in the plastic terminal block instead of four tabs. Rated to 30A and I suppose I'll forgo a start relay.

Taking a close look at the old heater box vs. New heater core, I decided to just build a new one. Nothing complicated just functional. The new core is 8"X10"X2" and should put out lots of heat.

I have really no idea if the old heater box is original to the car, but I'll probably list it for sale. It's in very good condition, and the 4"X5" heater core seems to be good.

I selected this heater core with due consideration of the outlet angles then changed my mind on the specific install orientation. As such the outlet tubes pointed the wrong direction. My hubris compelled me to re orient the tubes. Using the acetylene torch with very small flame, I melted the solder enough to spin the tubes to a better orientation. I did a minor vacuum check, it seemed good so in it went.

Well, as soon as I saw the tubes exit from the firewall, I hated it. I should have cut the tubes off at their bend and install them out straight.

Well, such as fate had it, there was a leak and out it came. I cut the tubes down, prepped well, and resoldered them. Seeing the tubes removed, I could see why theere was a leak. Instead of just spinning the tube, I should have pulled it out and properly prepped it for re-install.

I'm not set up to do a proper pressure test on the bench, but it's easy enough to give it a proper function test tomorrow. It's already back in, but I need to pick up slightly larger diameter heater hose. The stuff I picked up is very difficult to get on the nipples. It should be snug, but not need be forced on.

Previously the air was routed to the defrost where it Teed off to another hose which spilled air on the floor. I'm going to route the air to the defrost, and put two louver vents in the box cover for air to floor.