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I am upgrading a few things along with my new engine, and I have a couple wiring questions.
1. The new mini starter I have has the negative terminal, positive terminal, and a male spade terminal. My factory wiring has the 2 red power wires that clearly connect to the positive terminal, the ground wire that connects to my bellhousing bolt, and a purple wire with a ring connector. Do I cut off the ring connector from the purple wire and attach the included female spade connector to it, then connect it to the male spade terminal?
2. I am wiring up dual electric fans with the Ron Francis AR-78 wiring kit as suggested by others. Aside from the other wiring for the temp sensor and such, the kit only requires me to run a power wire to the fans, and to ground the fans to the frame. My fans come with the typical 2-wire hookups. What do you think the best way would be to connect this without cutting off the connector and hardwiring it all together?
Thanks for any advice you can give me! I can rebuild an engine and transmission, but electrical is voodoo to me.
As per your starter. I'm not looking at it. Is the solenoid terminal a spade connector on this starter?
I can't see it and it ain't stock.
There are no "ground" wires on a starter.
Your fans,.... There are a number of ways to trigger your fans. The name you mentioned means absolutely nothing to me.
Basic fan wiring, good 50 amp or greater power source. To a relay or relays. 30amp relay per fan or 50 amp or greater single relay for twin fans.
Trigger wire for relay or relays to temp switch in engine coolant system AND trinary switch in high pressure line of air-con.
Switching power to any good key on power source. Not much draw here, not super critical. Power out to fans. Ground from fans to good frame ground. The heavier the wires the better. Hard wiring much preferred to any electrical connectors.
Some really high amp loads on fan start up. Corroded terminal connectors cause resistance which cause heat. The fewer connections you have the fewer places you have for poor connections. Use high quality weather sealed connections when absolutely needed. Use over sized wiring for fan power and ground. Protect with a minimum 50 amp slow burn fuse.
Last edited by 4-vettes; Jul 27, 2024 at 06:57 AM.
This the what my starter terminals look like. Do I run the purple ignition switch wire to the spade terminal on the solenoid? I am assuming this is why the kit provides a female spade connector in the kit.
I also purchased these wiring connectors for my fans. I am thinking of connecting the grounds to the sway bar bracket directly on the frame... Or would anyone suggest anything else?
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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[QUOTE=Black72GTS;1608029194]This the what my starter terminals look like. Do I run the purple ignition switch wire to the spade terminal on the solenoid? I am assuming this is why the kit provides a female spade connector in the kit.
Your original two red wires connect to the terminal on the left side of your new solenoid.
Yes, the black wire is called a starter ground, although it is a ground for the fan and wiper motor and it connects to the bell housing or starter bolt.
Yes, change the terminal from round to flat as that is now the "S" wire.
Your year did not come with an "R" terminal
Yes the small spade terminal is the solenoid wire, your purple wire. The engine block should have a ground cable connected to the block just forward and above the stock starter motor and then over to the frame at the idler arm mounting location. Should be a fairly thick battery cable.
That is an interesting mini starter, I am not familiar with small standard type starters. I have a Gear drive starter on my 427 and I love the way it works. It spins the high compression 427 as fast as a Chrysler product in the 1970's.
It appears that you seem to have some sort of ground issue going on. I like to measure the battery voltage and then open the hood and test the voltage between the Horn relay (12+) and the engine (ground) and they numbers should be the very same. If not starting at the battery remove and clean the battery ground strap. Once the engine is bolted to the chassis it should be grounded well enough if the battery negative wire is clean at both ends. On older Corvettes the ground wire/strap is a potential problem with all the dirt and grime kicked up on the frame.
For my dual 11" SPAL fans I am using a DeRale PWM Electronic Fan Controller. It is nice because it reduces the noise in the engine compartment. The 2 fans both start at 50% power/speed and will slowly ramp up the fan speed as the engine gets hotter. Having had a couple relays and controllers fail I then made an extra harness attachment to allow me to run the fans directly from the battery. I am not willing to loose the cooling system while cruising. The controller and the fans have wiring that goes directly to the battery. If a controller fails I can still keep it cool.
Running multiple grounds can lead to problems so you might want to keep it to a minimum. Electric fans and EFI systems both need direct to the battery connections in my world. I have found batteries that had dual terminals on them, they have the top posts and side connections. This allows me to draw my electricity for the heavy duty accessories from the battery and keeps the noise down in the electrical system.
On my dual fans ( from a late C5) I went and found plugs that matched the ones coming from the fans. I made my elec connection to the plugs and then plugged them into the fans. I have an 86 TPI engine in my car so the computer controls one fan and the temp sensor from the block controls the other. Both go to relays under the hood. I have an extra power strip under the hood so I connected the power to the relays there. It is also a convenient place for a power source for other items, like elec headlight motors. On the other side of the engine bay I have a similar strip but for grounds. Have one heavy wire going to the block then I can connect any other grounds I need to the strip. The sensor from the block turns one fan on at about 190 and the ECU turns the second one on at about 200. FWIW I have a lot of Ron Francis wiring in my car and I am totally satisfied with it all, starting with the 24/7 fuse box that I mounted in the glove box.
I got everything wired up. I cut the ring terminal off the purple wire, soldered on a female spade terminal, and it works like a charm. I also soldered those T connectors in and ran my ground directly to the frame.
I have noticed that I have a slight run-on issue when I shut the ignition off, and I wonder if it connected to my fans. I have read that having electric fans running without a relay can cause a run on issue, but my fans are run through relays...
Wires to the relays:
- from ignition plug in fuse block
- from the starter terminal running to relay block
- temperature switch
Wires running from the relays:
- ground to the negative of the wiper motor
- to the electric fans
Spliced in wires for relay for AC control:
- spliced into AC compressor wire
- spliced into temperature switch wire
I have installed a brand new Tuff Stuff alternator, but now that I think of it, I did not attach the required 10ga wire to the grounding tab and run it to ground. Could this cause the dieseling? Where would a good ground be for that, considering my cylinder heads are aluminum?
I run a Tuff stuff alternator as well. I had to install a diode. I just bought one at the electrical shop. But they make plug and play ones. Ugly, but simple.
Give me a minute, I'll get a pic.
You can buy these. All over eBay and the like. Prevent feedback which causes run-on. These are inexpensive, work and are extremely ugly.
Or, open your harness along the inner fender and install a diode there and rewrap the harness. Not ugly, a tad more work. About a buck or two at any electrical shop.
That's the run on fix. Guaranteed.
As per grounding. The ground wire on the factory harness that attaches to the alternator is NOT there to ground the alternator, that's a ground for other things (lights) on the car.
The alternator grounds through it's mounting brackets and through the engine block. Then the large ground cable just forward and above the starter, over to the frame at the idler arm mounting location. That engine ground cable is very important to the efficiency of your charging system. But will not cause run on.
These modern replacement S10 -S12 Alternators can be run one wire or like factory 3 wire. They actually work MUCH better setup as a 3 wire Alternator. But because of the one wire capability. They lack the internal resistor of the original alternator that came on your car. And this power will back feed. A simple inexpensive fix. Just would be nice if Tuff Stuff would tell people about it.
No worries, we're here.
As per grounding. The ground wire on the factory harness that attaches to the alternator is NOT there to ground the alternator, that's a ground for other things (lights) on the car.
The alternator grounds through it's mounting brackets and through the engine block. Then the large ground cable just forward and above the starter, over to the frame at the idler arm mounting location. That engine ground cable is very important to the efficiency of your charging system. But will not cause run on.
These modern replacement S10 -S12 Alternators can be run one wire or like factory 3 wire. They actually work MUCH better setup as a 3 wire Alternator. But because of the one wire capability. They lack the internal resistor of the original alternator that came on your car. And this power will back feed. A simple inexpensive fix. Just would be nice if Tuff Stuff would tell people about it.
No worries, we're here.
Thanks for the advice. I will try and install a diode in the harness.
Where did you attach the grounding tab on the alternator to?
Grounding tab on alternator????
The ground bolt on the back of the alternator is there for ground wire in your harness.
It doesn't ground the alternator. Thought I had explained that. It provides a ground for other things on your car. You should have a black ground wire in the harness that goes to the back of the alternator and engine temperature sensor.
I'll get a pic. if your still confused.
Ok, so, as I stated earlier. The Alternator is grounded through it's brackets, through the engine block, through the ground cable mounted just forward and above the starter to the frame at the idler arm mounting location.
SO, With that in mind. Your question about a ground tab certainly has me baffled.
So, here are some pictures. My Alternator is a 140 Amp Tuff Stuff unit with powder coated cases. Diode is hiding on inside of the harness right here at this retaining clip. Most wouldn't notice the bump in the harness. And most wouldn't realize those headlight relays are not factory as well. Funny how most never see the obvious hidden in plain sight. OK, back side of my Tuff Stuff Alternator. Other than the color of the cases it should look exactly like yours. My ground wire was replaced with a larger one to match up with the main power wire purely for cosmetic reasons. The main power wire indeed needs to be much larger than stock. But this ground wire does not. But bigger doesn't hurt anything and it was done to look good.
Wiring Questions
I think the mini starters require you to add a diode on the voltage sensing wire at the alternator...
