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Electric fans killing ignition.

JoshIms

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Have a 1969 superbee with a 383. This winter sent my motor off for a rebuild/upgrade. Took forever... got to back about a month ago and have been slowly but surely getting it back in and getting car back together. Pretty much done but just went to install electric fan setup this evening. Four fan setup with two relays. Two fans per relay. Wiring and fan setup came together from wizard cooling. Followed instructions. Wired power and grounds directly to battery terminals and ignition power from clock behind dash. Started up for the first time to bleed coolant and see if fans would kick on when it came to temp. Stared fine and ran ok(didn’t idle well but new carb too and haven’t done a bit of tweaking yet) second fan kicked on car dies. Fans stay on and if key is on fans are still running but will not start back up. Once fans stop ( temp came below sensor temp) car starts again and once again fan kicks in and motor dies. Now car will not start even once fans turn off. Unplugged fans from relays and disconnected ignition power from clock still won’t start. Car has a post 1970 charging system with a 95 amp powermaster alternator. One thing I can add is my negative battery cable looks pretty weak and runs to the power steering pump bracket only. Only other ground wire is from back of aluminum head to firewall at voltage regulator. Not sure what my next step is and what could have been fried during this. Coil? Ballast resistor? Hoping to get some education from some of you guys as I only know enough to get my self into trouble. Thank s
 
Mopar electronic ignition? My guess is........

All those fans pull LOTS of current from the battery, relays or not. When the fans kick on, your battery voltage is dropping below the threshold voltage for the ignition ECU (orange box?). This will shut the car down as soon as that voltage hits a certain level (probably around 12.0 volts, they really prefer about 13.0 volts to run properly). It may run very rough for a bit before it stalls. After the fans are off for awhile, the battery voltage recovers somewhat, probably enough that the ignition will work again (so car starts again). After so many start/stall cycles of this happening, your battery voltage is not recovering above the ECU's voltage threshold, and hence, no start.

#1. Monitor your battery voltage at the TERMINALS to see what it is doing.
#2. Verify that your charging system is actually working and working correctly. (Again, at the battery terminals).
#3. You already mentioned the poor ground on your system. Fix it.

All this is a WAG given the small amount of info you have presented.
 
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BTW, really nice looking Super Bee in your avatar. Have any pics you can post of it? Here's a quick look at mine.

P6050023.JPG
 
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Here are the photos I have as I just got a new phone. So even though the car is still cranking over ok there may not be enough voltage to run the ignition? Once the ground is fixed if the problem continues are there things I can upgrade to reduce the voltage drop from the fans ? What does WAG mean?

F1CE5D51-CCF0-414F-AC05-02025376F428.jpeg 11D4243E-CD86-4154-888F-548FB49644FC.jpeg 2D5DCF4C-8129-408A-B773-BD38BCE8D90D.jpeg B16E73C3-284C-4AED-9EBE-798A6AE90A0E.jpeg 7C49CE51-CA68-476B-A380-30E5D5FD45D5.jpeg 2EBD8FD4-01BE-44FD-A1BB-DFDCC7EEC1B7.jpeg AC9A0E21-C5BD-409C-9E7E-25A963F04201.jpeg
 
Are the relays adequate amperage?
Fans use A LOT of power to get started. I used large relays to compensate the initial startup of amp draw.
Most alternators don't put out much juice at idle. As stated above, check your voltage at the battery during the different times: key off, key on, cranking, running at idle, running at 2k RPMs, and when fan(s) turn on.
Make sure your grounds are secure (battery to chassis, battery to engine, engine to chassis), and large enough wire is used.
 
Are the relays adequate amperage?
Fans use A LOT of power to get started. I used large relays to compensate the initial startup of amp draw.
Most alternators don't put out much juice at idle. As stated above, check your voltage at the battery during the different times: key off, key on, cranking, running at idle, running at 2k RPMs, and when fan(s) turn on.
Make sure your grounds are secure (battery to chassis, battery to engine, engine to chassis), and large enough wire is used.
Thanks it’s tough because now it won’t even start. Also I just Started it for the first time with the built motor and new carb back in the the car so still need to adjust the carb to get it to idle correctly. Right now the negative battery cable runs to the powersteeering bracket only need a better set up for sure and the relays came with the fan set up so I would hope they could handle it
 
Here are the photos I have as I just got a new phone. So even though the car is still cranking over ok there may not be enough voltage to run the ignition? Once the ground is fixed if the problem continues are there things I can upgrade to reduce the voltage drop from the fans ? What does WAG mean?

View attachment 625698 View attachment 625699 View attachment 625700 View attachment 625701 View attachment 625702 View attachment 625703 View attachment 625704

Pretty car, thanks for the photos. Is that a light blue interior?

So even though the car is still cranking over ok there may not be enough voltage to run the ignition? Exactly!

are there things I can upgrade to reduce the voltage drop from the fans ? Yes, get rid of them, a properly operating stock cooling system should work just fine.


What does WAG mean? Wild *** Guess. :thumbsup:
 
Charge your battery. It could be charged enough to crank, but not enough to get the car running.
Extra grounds won't hurt anything. Lol
 
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55CEA892-7701-4BCF-A356-86501E7234AD.jpeg
Black bench with a four speed

Pretty car, thanks for the photos. Is that a light blue interior?

So even though the car is still cranking over ok there may not be enough voltage to run the ignition? Exactly!

are there things I can upgrade to reduce the voltage drop from the fans ? Yes, get rid of them, a properly operating stock cooling system should work just fine.


What does WAG mean? Wild *** Guess. :thumbsup:
 
Did you contact wizard about this problem? Also add a second throttle spring, you never want to know what happens when the rare one fails.
 
Did you contact wizard about this problem? Also add a second throttle spring, you never want to know what happens when the rare one fails.
Have not yet but will. Thanks for the advise there are two springs one inside of the other but I could see where another would be smart
 
I know this isn’t the only cause of your problem, I never run a ground to an aluminum component. Manifold, water pump housing, heads, just not the best conductor. There should be a couple of threaded lugs on the front of the block behind thr PS pump. I ground the battery there and run a cable to the frame. High output alternator, high draw from the fans, plus electronic ignition can’t get by with a 4 ga. battery cable, 2 ga. minimum, bigger is even better. Electric fuel pump?
 
I know this isn’t the only cause of your problem, I never run a ground to an aluminum component. Manifold, water pump housing, heads, just not the best conductor. There should be a couple of threaded lugs on the front of the block behind thr PS pump. I ground the battery there and run a cable to the frame. High output alternator, high draw from the fans, plus electronic ignition can’t get by with a 4 ga. battery cable, 2 ga. minimum, bigger is even better. Electric fuel pump?
No mechanical fuel pump. Yea I had a feeling my grounds where not up to par has a beat up stock negative cable to the power steering bracket and a cable from my aluminum head to the fire wall at the voltage regulator only. That is defiantly my next step. I have heard I should update the wiring for my current from the alternator to the ammeter to the starter relay with a thicker gauge but don’t know exactly how to do this any advise on that topic
 
There are people on here a lot more savvy on wiring than I am. A 95 amp alternator probably should have at least a 6 ga. wire to the solenoid and on down to the starter or battery. If you’re still using an ammeter, don’t even think about running that much amperage through it, bypass your ammeter.
 
That seems to be what I’ve heard from allot of people guess I was lucky running it like that all last season. Fans just pushed it over the edge. Sucks car still won’t start must have fried something
 
9D96DE23-4AB0-40A9-86CD-1D37EE3A5E13.jpeg
Ok got it running! Actually best it has been since installing motor. So I had theses wires attached to upper terminals on the ballast resistor which I had to take apart for the motor guy to run it on a stand and didn’t remeber where they where before. Disconnected fans for now and moved wires to bottom and started right up even idled and ran great. Is this how the ballast should be set up on a 1969 car that has been upgraded to a electronic ignition? If so going to upgrade grounds and bypass anemeter with larger wire and hook fans back up with my fingers crossed
 
A '69 Super Bee did not come with the dual ballast resistor, it was a single. You want a single ballast with about 0.5 ohms resistance.

On the dual ballast like you have there, one set of terminals is 5.0 ohms (across horizontally) and the other set of terminals will be about 0.5 ohms (again horizontally). You most likely moved the wires to the 0.5 ohm resistor (the lower one) and that is why it now will run properly, much hotter spark.

Edit: Its also possible that the top terminal resistor is "open", you would get NO spark when you released the key. It should still have fired while cranking the engine over though.
 
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