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I need an electrical opinion on this issue

9K views 22 replies 9 participants last post by  hduff 
#1 ·
Okay
I have a 65 Falcon/Ranchero

I have recently rewired the whole car (not my first rodeo), using
a GM based harness kit

Added the GM bulkhead---and dealt with Ford's silly headlight switch

If any of you have ever looked at the FOMOCO ignition switches of yesteryear,
you can see how one would be very leary about upgrading an electrical system
and using the available switches and pigtails (looks like 16ga wire--maybe a 14ga feed)

So---I wire in a couple of relays----one for the ignition buss and one for the ACCY buss.

The ignition buss is powered thru the relay AND gets juice from the ignition switch (car keeps running in the event of relay failure.

Accy buss is powered solely by the relay

Today---I thought I would power up a couple of circuits

Circuits I wanted to test were good---AC, Stereo, dash lights,
Only put fuses in the circuits I was playing with.

Turn key off-----everything on the ACCY buss shuts off, but the ignition buss is still hot.

(While I was pondering this, my son called to come and get him as his car decided to not start on the opposite side of town)

With the key off-----oil and ALT lights still on---power to the wipers.
Did not really check the fuel gauge but should have.

Disconnect battery---everything dead----hook up battery----everything dead. Turn key on, everything fires up----turn key off, radio is off AC is dead
but still have dash power.

Is it possible for an ignition switch to do this?? It is the original and has been in a box for over a year not getting exercised.

Will probably get a new switch tomorrow after dealing with the offspring's car. (Towing involved---day off work involved)

Anyway---here is a diagram of how I have this thing wired---can you have a look and see if I overlooked anything?

 
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#7 ·
Nope----everything wired into that car I have drawn up, right down to
connector locations and pin locations.

There is a resistor AND the lamp in the Alternator excite lead.

This is car 4 or 5 that I have done, and I have solid reasons for the
modifications I made to it.

Not a whole lot on that ignition buss and the relay is probably not necessary.
(I will pull the relay in the morning and see what kind of results I get)
The relay is necessary on the ACCY buss.
Stock style ignition switch just cannot take what I plan on adding to this car in the future. Absolute stock appearance is needed in the interior and I will NOT use anything other than the FOMOCO switch for appearance reasons.
(Family owned car for 49 years)
 
#4 ·
. LOL! I knew what your question would be before I even finished reading... well, sort of, I thought you were going to say the engine kept running after the key was turned off... OK, same problem...

. The relay always has power to it... once you pull up the relay on your dual ignition wiring system, the relay backfeeds all the ignition wiring and keeps itself self-activated...

. Disco and reconnect battery and you start all over again...
 
#6 ·
Turning the key off should kill all power to the ignition and the relay coil.
Turns off the ACCY relay

I'm thinking that either the relay is sticking closed or the ignition switch is goofy.

turn the key off there is no path between the ignition buss and the battery
unless the relay contacts are sticky or the switch is holding just enough
current to light a pair of lights and pull a relay.

Even disconnected the ALT excite wire and turned off the ALT light
so there is no feedback from the alt (can't anyway without it running), thru the excite.

I'll play with this some more tomorrow after I get the kid's car to a shop
 
#8 · (Edited)
So---I wire in a couple of relays----one for the ignition buss and one for the ACCY buss.

The ignition buss is powered thru the relay AND gets juice from the ignition switch (car keeps running in the event of relay failure.
. As soon as I read that, I knew what your question would be...

. If the relay was sticking, disconnecting the battery wouldn't matter... everything would power back up as soon as you reconnected the battery...

. I assume the ignition switch activates the relay #85, but the relay always gets direct high amp power on it's other terminal #30 from the battery (hopefully via a fuse or fusible link or circuit breaker)...

. That "AND" tells me you have a wire not on your wiring diagram...
 
#9 ·
. As soon as I read that, I knew what your question would be...

. If the relay was sticking, disconnecting the battery wouldn't matter... everything would power back up as soon as you reconnected the battery...

. I assume the ignition switch activates the relay #85, but the relay always gets direct high amp power on it's other terminal #30 from the battery (hopefully via a fuse or fusible link or circuit breaker)...

. That "AND" tells me you have a wire not on your wiring diagram...
My mistake----it is wired just as it is drawn up.
The buss is solely powered by the relay.

The car is wired so that in the event of a relay failure, just the coil and the ALT light will be kept powered up by the switch.

Time for a nap----will update tomorrow
 
#14 ·
Yep----went back this morning to play with the car after
rescuing my son's car from the college parking lot
(whole new can 'o' worms).

Pulled the relay --and sure enough I managed to to tie the ignition buss
to the ignition switch:rolleyes:. Everything works (fuse box related) just like it is supposed to----shuts off when it's supposed to as well

Removed the ignition switch-----yep, the ignition lead
is giving continuity straight to that buss.

There are are only a couple of spots in the harness that may have happened,
but I don't think I worry about it too much.
(Dumb-Blond-blue eyed-Pollack moment I guess)
Only items on that buss-----coil(direct from ignition switch), wipers, turn signals. and elect choke.

Pretty sure the ignition switch can handle that with no issues at all.
The ACCY buss has the big loads on it, and it is working properly.

Found another problem tho-----silly instrument cluster voltage regulator died.
Pricey little sucker that thing is.
Bought a new one----brand new ICVR is dead.
LAST ONE IN TOWN TOO
Replacement coming in from Houston in the morning (I hope)

12v going in----nothing coming out. Pretty sure I should be seeing 5.5 volts
on the "out" side.
Even tried the hooking up a bulb to the output (so it would 'see' a load),
No strobing light at all.
Both my original and the replacement got hot enough they had to cool before I could remove them (this is not good---right?)

Cluster out of the car and feeding the cluster both directly to the ICVR and then also thru the connector harness---same results
(yes, a ground path from the cluster back to the battery was in place)
Good thing is---all the indicator lamps work----just no temp or fuel gage.

Hoping to get this worked out tomorrow (after some dealing with the kid's car). Just had all my plastic dash trim re-plated and every time I have to pull the cluster, I risk scratching it up.

Discovered on the kid's car today----no fuel getting to the rails
Car will start on starting fluid---
Disconnected the fuel line to the rail---turned key on
Can hear pump running, but not a drop of fuel.
Kid drove it to school---would not start when he was ready to leave.
Had to make arrangements with the college to let it stay overnight,
and then had to have it out of there by 8am this morning.
 
#17 ·
Got the kid's car going a couple of hours ago

The pump / sender Assy was only about 1-1/2 years old.

Filter was free, the pump was not pumping

new assy-----car started right up

Why does this have to happen with a full tank???

On the instrument cluster voltage regulator-----got a new one delivered this morning.
Everything in the cluster is now working as it should.
Cluster back in with no damage
Might even fire up the new engine this upcoming week.
Just gonna make sure the tank is empty before I add some fuel.
(Working fuel gage tells me it is ALMOST empty)
 
#19 ·
Bad couple of weekends
after fixing the kid's car.
My lawnmower tossed a rod immediately after changing blades
Next day---borrow/steal neighbors trailer to go get new mower----
----back into HER Crown Vic when I got home.
Back of that trailer is invisible from the truck----dammit.
Tore the rear bumper cover.

Mow yard with new mower

Piddle with Ranchero all week and deal with a "fuel turned into sludge and plugged up sending unit) thing----and made arrangements to fix the back bumper of the Crown vic

Today----fully prepared to instal the steering column into the Ranchero one last time----this goes well.
Put some fuel in the tank of the Ranchero
disconnect ignition lead to the coil and crank the engine.
Oil pressure light goes out (good thing) but having issues getting the fuel up to the carb.:rolleyes:
Took a bit of cranking but eventually it came up and filled the carb.
Now---not enough juice left in the battery to fire the car up:pain:

Hook up charger ------ wife calls-----she just wrecked the Crown Vic:pain:

Nobody hurt----3 cars----amazingly, everyone had insurance.

Little while she comes to the body shop where I spend my Saturdays (and an hour or two after work during the week), so we can have a looksee at what needs to be done to her car.
Strange---everything not metal was pretty much destroyed on the front.
May have bent the bumper bar down a bit---not sure yet.
Not a scratch on any metal---no bends in any metal up front at all
Fenders---hood ----perfect. Usually when the header panel goes, it takes some of the hood----when a bumper is destroyed, the front fenders also take a hit.

Car still drivable, so she goes on home.

I unhook the charger from the Ranchero.
Car fires right up-----no playing with the distributor, no playing with carb.
Starts up and idles just fine:D.

Now----not nearly as cranky as I was a couple of hours ago when 2 weekends in row have taken me for everything I have.

Will hit the engine with a timing light and let it warm up some next week.
about 4' of exhaust pipe and no mufflers ---- a bit of a cam---sounds like this will be a fun one.

Oh----carbed 5.0 HO ( it is a roller cammed motor) into a 4-spd 65 Ranchero----should be fun
when the car is completely reassembled again
 
#22 ·
I actually do this in Paint.
Sometimes I have nothing better to do, and the more I do it
the better I get at it:D



To Rusty Rockerpanels
Everything is working as it should now, just the ignition relay is not in place.
With a little testing I know where I miswired it---all I need to do is cut one
of two wires in the harness and it will work as I had originally planned.
Just not sure which wire because both are the same gauge color.

Not gonna worry about it for a while----started working on the body.
Just wanted the car running so it could move under it's own power
 
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