Author Topic: starter solenoid wiring (Read 12170 times)

jsherrod · « **on:** August 10, 2012, 10:59:47 PM »

Had to replace solenoid, the old one had a wire (green) that plugs into the bottom. But my new one doesnt have that connection, and im not sure what that wire is for?? currently the car wont start and im not getting any spark. This is my first amc and im a lil lost... thanks

vangremlin · « **Reply #1 on:** August 10, 2012, 11:19:15 PM »

The connection on the bottom is for the neutral safety switch. Do you have an automatic or manual? SOunds like you may have the wrong solenoid.

captspillane · « **Reply #2 on:** August 10, 2012, 11:38:49 PM »

The solenoid you're describing is a stickshift soleniod that grounds to the body through the mounting screws, which is exactly what you want. The original solenoids in all your automatic Eagles have a stud at the bottom that provides the ground for the solenoid coils. It is a very weak ground and it is very unreliable. Replacing the solenoid with a studless stickshift version is one of the very first things I do to all my automatic Eagles. I consider it a critical upgrade. There are several major advantages and no danger of damage to the car.

Is the starter turning the engine over? If so then your solenoid and starter are working fine. Is the engine getting fuel? I'll guess its a bad ignition module. First thing you should do is buy a new one and plug it in. If its not that, then keep the new one under your seat for the day the old one eventually breaks. It will not be a wasted purchase.

txjeeptx · « **Reply #3 on:** August 10, 2012, 11:54:26 PM »

Wasn't sure if that lil blue/green wire was the ground connection for the auto solenoid. That is information that has been overwritten in my brain. Thanks for reminding me.

So, if you replace the solenoid in an automatic car with one for a manual car, you just leave the blue/green wire disconnected from anything and tuck it away.

To help the OP, you need to make sure the "I" terminal to the solenoid is connected to the ignition wiring circuit, and the "S" terminal of the solenoid is connected to a circuit that is only hot when the key is turned to the start position. Reverse them and you'll either get nothing at all, no starter - no nada, or the starter will engage the moment you turn the key, but there will be no spark, and the starter will stay engaged until you turn the key to the off position. I don't recall exactly, overwrote that stuff too.

mudkicker715 · « **Reply #4 on:** August 11, 2012, 01:21:54 AM »

Quote from: captspillane on August 10, 2012, 11:38:49 PM

The solenoid you're describing is a stickshift soleniod that grounds to the body through the mounting screws, which is exactly what you want. The original solenoids in all your automatic Eagles have a stud at the bottom that provides the ground for the solenoid coils. It is a very weak ground and it is very unreliable. Replacing the solenoid with a studless stickshift version is one of the very first things I do to all my automatic Eagles. I consider it a critical upgrade. There are several major advantages and no danger of damage to the car.

Is the starter turning the engine over? If so then your solenoid and starter are working fine. Is the engine getting fuel? I'll guess its a bad ignition module. First thing you should do is buy a new one and plug it in. If its not that, then keep the new one under your seat for the day the old one eventually breaks. It will not be a wasted purchase.

i don't believe its weak or unreliable. however bypassing the neutral safety switch can have certain risks.

jsherrod · « **Reply #5 on:** August 11, 2012, 08:16:13 AM »

yeah the motor cranks but just wont fire up... i did find a bad fuel line but i already replaced it and still the same thing... cranks but nothing. This is my first carb car that i have owned, but from my lil knowledge im guessing the ignition module or bad ground?

amcinstaller · « **Reply #6 on:** August 11, 2012, 08:34:09 AM »

Quote from: mudkicker715 on August 11, 2012, 01:21:54 AM

i don't believe its weak or unreliable. however bypassing the neutral safety switch can have certain risks.

yea, this sounds more familiar. i did this once, replaced a bad solenoid with a known good one from a std car into an auto and the car would start in any gear

captspillane · « **Reply #7 on:** August 11, 2012, 09:04:02 AM »

Yes, eliminating that will let it start in any gear, just like a stickshift car. That is a critical upgrade in my opinion. The only way it could damage the car is if you turned the key in a parking spot while still in drive, lurching forward and hitting the car in front of you. Anyone who has switched from automatic to stickshift on a regular basis has lurched forward when they've turned the key while in gear. Its not that big of a deal. Develop good habits and there is no danger of that happening.

Put the brake pedal down each and every time you reach for the key and the starter is not strong enough to overcome the brake even if you did have it in "Drive." Likewise that is an important habit to develop for stickshift, since it sometimes slips into fourth when you think its in neutral. I've never shut down the car and gotten out of it without jiggling it to make sure it was in park and I never allow myself to turn the key without the brake pedal depressed, so I have no fear of damaging the car.

When a vacuum line breaks as you're driving and the car goes from running smoothly to barely running in an instant, then it's a very valuable resource to be able to start the car while driving. If you're running a stock Eagle with a Carter Carb, this will happen to you eventually. Using the starter to move the car from a standstill has been a very valuable resource several times for me as well. I've had Eagle solenoids quit working dozens of times over the years, and the vast majority of them would work fine as soon as it was properly grounded.

When I create my own wiring harness I will eliminate the Neutral Safety Switch and instead wire it to prevent the starter from starting unless the brake pedal is depressed. That is how some newer cars are set up now.

jsherrod · « **Reply #8 on:** August 11, 2012, 09:16:42 PM »

I got the eagle to start. It was the ignition module, so thanks and congrats to whoever said that... however now that it runs, it has a new prob.. its just stalls right out. Someone has set the idle in park to 2000rpms so it dowsnt stall there, but as soon as u shift to drive...dead... it will drive, but once u let off the gas...stalll.... i thought it was the alternator, but i replace it and am getting the right volts now... any ideas??? thanks

TheWraith · « **Reply #9 on:** August 12, 2012, 12:45:52 AM »

A good vacuum leak could cause this.

And double check the repaired fuel line, just for GP.

My first car, a '72 Nova, did something similiar. Turned out the PO messed with the wiring and got it too close to the exhaust manifold. It woud start, but when I shifted into gear (auto) the engine would torque to one side and ground out the wire on the exhaust manifold. That's my long way of suggesting you start eyeballing the wiring since you were just in there working with it.

amcinstaller · « **Reply #10 on:** August 12, 2012, 06:54:25 PM »

only cars set up to crank only with brake are push to start cars with smart keys. honestly just leave the neutral safety. this is one system i think the factory put there for a reason, and should be retained. even if you have good habits, all it takes is one time to not be thinking and bang, youve hit a car, or worse a person. or someone else drives the car, same problem. install the proper soleniod if you change it.

Baskinator · « **Reply #11 on:** September 28, 2012, 12:46:09 PM »

I run without the NSS also and have already been in situations where this has saved me, like the capt mentioned. The auto solenoids are too troublesome, and more expensive anyway. I would never park ANY auto car in drive, that's just stupid. How it would move there, I don't know, but I always check the shifter position twice and have my foot on the brake while starting. I don't let anyone else drive my Eagle, especially since it's a 30 yr old car with a few quirks, and I generally park away from other cars if possible. These things are all habit, I don't have to think about them. Works for me, less problems.

amcinstaller · « **Reply #12 on:** September 29, 2012, 12:37:04 AM »

Quote from: Baskinator on September 28, 2012, 12:46:09 PM

been in situations where this has saved me, like the capt mentioned

how?

mudkicker715 · « **Reply #13 on:** September 29, 2012, 08:16:14 AM »

Quote from: captspillane on August 11, 2012, 09:04:02 AM

Yes, eliminating that will let it start in any gear, just like a stickshift car. That is a critical upgrade in my opinion. The only way it could damage the car is if you turned the key in a parking spot while still in drive, lurching forward and hitting the car in front of you.

so this spoken from someone who obivously has no fear of losing his keys to a "youngen" who plays with cars and would love nothing more than to do the real thing. i know the chances of that happening are zero but the cost of deleting a safety feature like that could be high.

so if its a bad carb you compensate by deleting this feature for. fix the carb and maybe save money in gas.

captspillane · « **Reply #14 on:** October 03, 2012, 06:51:14 PM »

I just bought another beautiful Eagle station wagon three days ago. It idles beauitifully and rides nicely with 53K original miles. Recently rebuilt carb. I've driven it about 200 miles since then as is.

It has stalled out four times while driving for no apparent reason and with no signs of a problem before or after. The NSS is still hooked up and my attempts at finding neutral while turning and merging with traffic came extremely close to crashing it just yesterday. One other time I accidentally put it in park while still moving and almost ruined the parking mechanism as my forehead bounced off the steering wheel. All four of those times would have been a quick effortless reach for the key with this minor modification. It is not safe and should not be necessary to reach for the gear shift lever while driving.

I should not have driven it home with the NSS still hooked up. The car nearly got destroyed already because I didn't.

captspillane · « **Reply #15 on:** October 03, 2012, 07:46:09 PM »

I didn't panic. I reached down, clicked it firmly into neutral, reached for the key, it didn't start, I reached down again, wiggled it, didn't start, then I had ran out of road and had a problem where I had to give up on starting it and crank on the steering wheel while slamming the brakes to keep from crashing. You have to be in exactly the right spot for neutral to work.

Part of the issue is both the NSS itself and the gear shift lever. It won't connect reliably even when the transmission is in neutral. When I slammed it into Park while still moving it was after getting frustrated with several attempts to start in neutral. The NSS in the transmission not working or the wire to the solenoid fatiguing and breaking are both related and common problems. The whole system is a constant problem unique to AMC cars. Keep in mind no one would ever bother disabling an NSS in a Jeep Cherokee or any other car I've ever heard of.

An automatic solenoid will also stop working much sooner and more often due to corrosion than a manual one because the manual ones get a stronger ground through the screws than the wire post. I've had to replace one manual one and dozens of automatic ones, even when I used to ground them with alligator clips directly to the battery.

amcinstaller · « **Reply #16 on:** October 03, 2012, 08:10:19 PM »

actually you almost crashed because your carb sucks.

captspillane · « **Reply #17 on:** October 03, 2012, 08:19:41 PM »

True that. One day it will be fuel injected with an AW4 and working NSS, but there is many thousands of hours and dollars between today and that day. When I needed a reliable car for my family I bought a Jeep Cherokee for four times as much as I paid for this Eagle.

In the meantime I putter around quite happy in my dirt cheap antique AMC Eagle with a NSS disabled.

mudkicker715 · « **Reply #18 on:** October 04, 2012, 07:46:30 AM »

so if you fix the carb with a rebuild kit make it actually work. say $40. get your linkage aligned correctly to neutral $0.

still willing to bet you save money in the long run with your carb running happy. plus its safer. realize eagles do not die driving around corners unless somthing is wrong.

amcinstaller · « **Reply #19 on:** October 04, 2012, 02:23:13 PM »

one of my spirits would die when i bought it (std car not auto) but a plug set and a carb later, ran great, never stalled again, unless i sucked that day

jim · « **Reply #20 on:** October 04, 2012, 08:28:36 PM »

Maybe the ICM? That fixed both of mine when they would die, sometimes going around corners.