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Username Post: Wiring my 57, 2nd set of questions        (Topic#272674)
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
11-26-11 08:20 PM - Post#2162121    

Thanks to everyone who is helping me with this project. To be honest, it is confusing for me.

Here is my not to scale diagram

Here is a photo of the starter solenoid, the wires on it now just temporary.

Here are my questions and comments. Some are just repeating what you guys told me to make sure I understand.
1. I will be using 1/0 Welding Cable for the battery cable. From the Battery/Cut Off/Remote Solenoid/Starter Solenoid.
2. The Kit as a Purple wire Marked Starter S, this will go on the "S" on the remote solenoid. The Yellow wire is not used. There is also a red wire marked 12V Battery, I do not need this on since the battery is in the trunk and connecting directly to the Master Cut off.
3. On my starter solenoid which is B R and S? I labeled the diagram with a 1, 2 and 3.
4. A wire is going to run from my starter to my alternator, from which post of the starter will it connect?

It is my goal to get the above connected before I move onto the next step. I really appreciate everybody's input. Please let me know if I am missing something or about to do it wrong.
Thanks,
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
acardon 
Senior Member
Posts: 9816
acardon
Loc: DFW TEXAS
Reg: 03-25-05
11-26-11 10:23 PM - Post#2162163    
    In response to Charlie57

  • Quote:
3. On my starter solenoid which is B R and S? I labeled the diagram with a 1, 2 and 3.
4. A wire is going to run from my starter to my alternator, from which post of the starter will it connect?





3. The short cable from the starter motor is 3. The small terminal is 2 and the other large terminal is 1.
4. If you run a wire from the alternator to the starter, it would go to the 1 terminal BUT it effectively negates the purpose of the remote solenoid, since that will put power on the cable from the remote solenoid to the starter all the time the engine is running. AND it will keep the starter energized all the time because of the jumper to the "sol" (#2) terminal.

What is operating the battery cutoff with remote? Why do you have 2 cut off solenoids in series?
Don
66 Corvair (driving)
57 2dr HT (driving)
56 2dr HT (waiting to be restored)


Edited by acardon on 11-26-11 10:26 PM. Reason for edit: No reason given.

 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
11-26-11 11:48 PM - Post#2162180    
    In response to acardon

Don,
Thanks for replying, the Battery Cut Off is actually Painless "Remote Master Disconnect Kit" #30204. It uses a toggle switch which I can place any where in the car. From there I have a Jeg's Remote Location Starter Solenoid Kit #10301. I installed this because I have read that engines which put out excessive heat can cause the starter solenoid to over heat. Since my engine is pushing 500HP I thought it would be a good move.

What is the purpose of the wire running from the alternator to the starter? What happens when I don't have one?

Thanks,
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
acardon 
Senior Member
Posts: 9816
acardon
Loc: DFW TEXAS
Reg: 03-25-05
11-27-11 07:59 AM - Post#2162237    
    In response to Charlie57

  • Quote:
What is the purpose of the wire running from the alternator to the starter? What happens when I don't have one?





The reason that most wiring systems have the alternator wired to the starter, it's a convient tie point to get voltage from the alternator back to the battery and to the other areas of the car such as the fuse panel and ignition switch. Because of the remote solenoids, and the jumper from the battery cable on the starter to the "sol" terminal of the starter, you can not wire the alternator to the starter. #1, it will keep the starter energized all the time and #2, it will not get any voltage to the battery to charge it. With your set up, you will need a heavy gauge wire (6 to 10 gauge), (depending on the output of the alternator), from the alternator to the battery. You will also need to get power from the battery to the dash, so a terminal block up front is a necessity to connect the battery and alternator to.
The 2 remote solenoids is like having 2 light switches in series to turn on a light, they both have to be on to turn the light on, but either one will turn the light off. One of them is reduntant to kill voltage to the starter. If it's for security, you could put the hidden switch in the purple wire between the ignition switch and the remote start solenoid.

Don
66 Corvair (driving)
57 2dr HT (driving)
56 2dr HT (waiting to be restored)


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
11-27-11 06:34 PM - Post#2162448    
    In response to acardon

I have corrected the upside down solenoid. The instructions from JEG's had the I and S at the top of the Solenoid which is why I mounted it upside down. They have since corrected their diagram.
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
11-28-11 03:52 PM - Post#2162752    
    In response to Charlie57

We went to Phoenix to visit the grand kids last week and I still got to work on my car. When time allowed I started working out some electrical details as I will be wiring it soon. I prepared several diagrams that I will post later so I can get opinions on the circuits.

One of the diagrams shown below is for a main power disconnect as required by NHRA. There must be an external switch that track personnel can push to kill all electrical power in the car for safety reasons. The problem is if you simply disconnect the battery the engine will continue to run off of the alternator output. Wiring the ignition system to the disconnect switch will not kill the engine either because it would still be powered up from the battery side of the switch. Not to mention the regulation says all “disconnect all electrical power” which would remain hot on everything except the ignition if it would even work that way which it won’t.

This is what I came up with. It will require an 8 ga. Wire from front to back to charge the battery as well as another one as a main power distribution circuit back to the front of the car. Once the disconnect open the circuit the only live wire remaining will be the cable from the battery to the disconnect switch and the 8 ga. Charge wire from the alternator to the battery side of the disconnect switch. This will turn everything else off in the car.

The control wiring has been omitted for clarity. The cable from the ford relay (some call it a solenoid) to the starter is only hot during cranking.


Opinions are welcome.

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
acardon 
Senior Member
Posts: 9816
acardon
Loc: DFW TEXAS
Reg: 03-25-05
11-28-11 06:40 PM - Post#2162830    
    In response to 72novaproject

Steve, are you sure that the 8 gauge charge wire will pass inspection, since you will still have power on the wire to the alternator?

Don
66 Corvair (driving)
57 2dr HT (driving)
56 2dr HT (waiting to be restored)


Edited by acardon on 11-28-11 07:03 PM. Reason for edit: No reason given.

 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
11-29-11 06:49 AM - Post#2162996    
    In response to acardon

  • acardon Said:
Steve, are you sure that the 8 gauge charge wire will pass inspection, since you will still have power on the wire to the alternator?



Don, no, I am not. After all my years as a technician I have never driven a car on a drag strip or gone through a technical inspection so I don’t know how picky they will be.

I have read about this circuit on a Nova specific site in their drag racing forum (did a search) and really didn’t get any clear answers even though I wasn’t the one asking the question. Most people rig it to the ignition somehow which I couldn’t grasp and they offered no schematics for their connections.

The circuit would be the same regardless of where the components are located but either way the alternator output has to be isolated from the main power distribution through the car for the disconnect to be able to kill the engine.

If someone else can design a better circuit I would be interested in seeing it. The one I posted is the only way I can see to make it work. After drawing the circuit I just re-read the NHRA regulation as follows and I should be fine. My circuit does “stop all electrical functions”.

General Regulations Section 20, page 34
8:4 MASTER CUTOFF


Mandatory when battery is relocated, or as outlined in Class
Requirements. An electrical power cutoff switch (one only) must be
installed on the rearmost part of each vehicle and be easily
accessible from outside the car body. This cutoff switch must be
connected to the positive side of the electrical system and must
stop all electrical functions including magneto ignition. The off
position must be clearly indicated with the word “OFF.” If switch is
“push/pull” type, “push” must be the action for shutting off the
electrical system, “pull” to turn it on. Any rods or cables used to
activate the switch must be minimum 1/8-inch diameter. Plastic or
keyed switches prohibited. Switches and/or controls must be
located behind rear wheels on rear-engine dragsters.

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
11-29-11 07:45 PM - Post#2163322    
    In response to 72novaproject

Steve,
Thanks for posting your drawing. It looks like I might get sometime this weekend to work on my car. I'm sure I'll have more questions.
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
11-30-11 08:50 AM - Post#2163479    
    In response to Charlie57

Charlie, here is a link to an instruction set for a switch similar to yours. Sorry I don’t know how to post a PDF diagram so you will have to follow the link. There are a lot of different ways to do this and this diagram is just one of them. I would use this method if my battery was in the trunk, the positive cable was hot all the time at the starter motor serving as the main power distribution point for the electrical system and I didn’t need to comply with NHRA regulations. I would also mount the disconnect switch in the engine compartment in that situation.

The point is that the alternator output and the battery have to both be isolated from the remainder of the electrical system when the switch is in the open (off) position.

Let us know if you hit a snag. (fishing term used by southern boys)

Link to wiring diagram

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
Vaughn 
"12th Year" Gold Supporting Member
Posts: 15391

Loc: Colorado Springs, CO
Reg: 08-08-04
12-01-11 09:05 PM - Post#2164027    
    In response to 72novaproject

Although you have mounted the remote starter solenoid so that it is right side up, you have the large cables switched.

Power input from the battery (or the battery cut off switch) feeds into the left side of the solenoid as you are looking at it, and then the output to the starter comes out of the right side. Yes, this does make a difference.

The easy way to think about the labels on solenoids:
The S terminal (or solenoid) is used to activate the solenoid. Usually, on the solenoids you need to think of "S" for start, and R for run/I for ignition (although that is not what they stand for, it is "S" for solenoid and R for relay). The I terminal is used to power points ignition systems - which you do not have, so it will not be connected to anything.

 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
12-02-11 09:44 PM - Post#2164323    
    In response to Vaughn

Here is part of the reason I have been confused, this is the "revised" instructions for my remote soleniod. I have it labeled this way, HOWEVER, the instructions they sent with my solenoid looked the exact same except the S and I terminals were at the top of the solenoid. This made it look like the solenoid was upset down which is how I mounted it. Do you guys think these are wrong? I would not be surprised.
Charlie

"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
acardon 
Senior Member
Posts: 9816
acardon
Loc: DFW TEXAS
Reg: 03-25-05
12-03-11 08:30 AM - Post#2164458    
    In response to Charlie57

I have never heard of a solenoid failing to operate upside down. There is nothing in the solenoid that is gravity operated. It has a spring to open it and an electro magnet to close it. The reason to show it in one position is to prevent confusion of the S and I terminals, that would be on the opposite sides.
Don
66 Corvair (driving)
57 2dr HT (driving)
56 2dr HT (waiting to be restored)


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-03-11 09:31 AM - Post#2164483    
    In response to acardon

Charlie, if you will provide me with the name and model number of your battery disconnect or the instruction sheet I will draw you a diagram of how to wire it into your AAW harness with colors and everything. I need to know a few things first though.

Where is your battery? In the picture I can’t tell which lug is which coming through the floor. The ford solenoid and the power disconnect are mounted behind the rear seat (cabin rear bulkhead on the trunk side).

Do you want the positive battery cable going to the starter motor electrically dead while you are driving down the road? I would if it runs under the car.

Where is your main power distribution point that feeds high amperage power to your fuse panel? Typically this is on the starter solenoid but that will need to be re-engineered with the above modifications.

Do you intend to activate the main power disconnect from a toggle switch mounted in the cabin? If so you may need one for the battery and one for the alternator. This is in addition to the ford solenoid used for heat soak prevention. I think I would re-think all that if it were me. You will be running down the road with two continuous duty solenoids engaged just to keep the car running. Continuous duty solenoids tend to not be so continuous sometime. You said you have an MSD and as mentioned above don’t forget the diode or you will fry the MSD box.

OTHER CONSIDERATIONS:

If you have a permanent magnet or mini starter the jumper blade on the starter won’t work.

Not all cars heat soak. The problem (in my opinion) is the windings inside the starter mounted solenoid. The remote starter solenoid (ford type) still uses the windings inside the starter mounted solenoid so all it does is provide more amperage to the starter mounted solenoid. Resistance creates heat and heat creates resistance. Making sure you have a good 12 ga. Wire to the factory solenoid and a full 13.8 to 14.2 volts to the start terminal will do the same thing as the remote solenoid.

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
12-03-11 11:19 PM - Post#2164751    
    In response to 72novaproject

Hello Steve,
I will take any help I can get and plus you guys are teaching me a lot about this. I am not even sure of all the questions you are asking but here is what I know.

The Disconnect is Painless #30204. The solenoid is Jegs #10301.

I have not purchased a battery yet but in my photo it will set just to the left, the cable coming off the disconnect will go to the positive and the negative would go to the other bulkhead in the floor and then on to the frame.

The positive battery cable to the starter will be ran under the car, along the frame. It seems like it should be dead going down the road.

Where is my main power disconnect? I have not gotten that far yet and not 100% I understand. I am assuming it is the main power going to the fuse box? I have not read about that yet.

I do plan to run the toggle switch in the interior, somewhere.

I guess I do have a mini starter, I just know it is smaller then most the others I have had, I will try to take a photo of it tomorrow.

Here are a couple of general questions. I thought about putting a terminal block in the trunk, maybe for the amp and anything else. I want to run a battery tender once I get the battery. I still have to ground my solenoid. How should I ground my battery cable to the frame?

I am having some crimping issues and I plan to post a question about using my crimpers.

Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-05-11 04:25 PM - Post#2165386    
    In response to Charlie57

  • Charlie57 Said:
Where is my main power disconnect? I have not gotten that far yet and not 100% I understand. I am assuming it is the main power going to the fuse box? I have not read about that yet.



I think you meant main power distribution. Think of it like the power lines coming from the power pole at the street to your house. The main power distribution in your house is your breaker panel but a car with DC voltage is a little different because voltage drop is greater with DC. On your car you have the battery and alternator that provide the power but it is not always convenient to run all your wires to the battery. The factory ran the positive battery cable to the starter and from there a couple of heavy wires fed the fuse panel. These were protected by fusible links and everything past the fuse panel was protected by well, the fuses. We are putting devices (loads) in places the factory never intended them to be and drawing more power so we have to re-engineer things a bit. We need a larger main power distribution system to handle the additional load at all of the locations around the car. You should think of this as the foundation of your electrical system and build everything else off of it.

Charlie, I have a pretty good idea what you want to do and I have been working through some of these same circuits myself as I am about to wire my car. I will put something together in the next few days and post it here so you can look at it.

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
12-05-11 08:06 PM - Post#2165471    
    In response to 72novaproject

Steve,
I appreciate it and will be watching for your post. I thought I understood this better but I guess I do not. I might even buy an auto wiring book, I always like to know why you do something. I know I want to do it right. I was looking at the other circuits last night, somethings seem easy to understand and others do not. I still have to figure out four power windows, locks, stereo with bass and amp, electric seat, vintage air, electric cooling fan, electric fuel pump and a big desire to hide the wires in the engine compartment.
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-08-11 08:02 AM - Post#2166289    
    In response to Charlie57

Charlie, this is exactly how I am going to wire this circuit in my car. The only difference is you have an electric disconnect and I have a manual one.

I have noted where the AAW wires are used. Discard the yellow wire or use it for something else. You can keep adding junctions and put as many of them as you want anywhere you want. Just always be aware of where the circuit protection is and you will be fine.

Drawing the diagrams helps me think my way through the circuits. If I can’t make it work on paper I can expect poor results on the car. All this wiring may seem complex but if you will just work on one circuit at a time until you understand it eventually your car will be completely wired. The attached diagram is only the foundation of your electrical system.

Hope this helps,

Steve

To each problem exists a solution...now think.

The ZD Nova Page


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
12-17-11 07:58 AM - Post#2169661    
    In response to 72novaproject

Steve,
Thank You for taking the time to do this. It is going to help me a lot. I have been tryng to get moving on this project but I have a few personal things getting in the way, a new job, training for the new job and fixing up my 89 F150 so that it can become my daily driver.
I believe this weekend I can work on this a bit.
So far my question is:
Is the Purple Start wire,needed because I have a high torque starter?
I am sure I have more questions to come.
Thanks Again,
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
65_Impala 
Very Senior Member
Posts: 2333

Reg: 12-29-02
12-17-11 04:44 PM - Post#2169816    
    In response to Charlie57

Usually, the Bat and S terminals on the starter are just jumpered and then the purple goes to the Ford solenoid to energize it.

The purple is the wire that is energized when the key is turned to the start position and it is used to engage the solenoid, either the Ford one or the one on the starter.

Honestly, with a mini-starter you could eliminate the Ford solenoid as long as you are OK with the wire to the starter being live all the time. Othewise, run the purple to the Ford solenoid and jumper the S and Bat terminals on the starter.

Peter


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-21-11 07:31 AM - Post#2170884    
    In response to 65_Impala

Most mini starters are permanent magnet starters and will generate a voltage as they coast down. If you “jumper” that type of starter it will keep the pinion gear engaged after you release the key.

If you don’t mind the battery cable staying hot all the time you can eliminate the ford solenoid all together. If so, wire it like this:



Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
Charlie57 
Valued Contributor
Posts: 2990
Charlie57
Loc: Lebanon, Tennessee
Reg: 03-30-08
12-22-11 04:55 AM - Post#2171150    
    In response to 72novaproject

I was told to add the remote solenoid to help prevent heat issues on the started mounted solenoid. Unless this is not true I'll use the remote solenoid. My question now is if I use the remote can the purple wire be attached directly to the remote solenoid or directly to the starter mounted solenoid or does it need to be spliced in along the wire between the two?
Charlie
"Charlie's 57 Chevy" I made it's very own FaceBook page please visit and "Like"
http://www.facebook.com/pages/Charlies-1957-C hevy/214078481937849


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-22-11 08:02 AM - Post#2171172    
    In response to Charlie57

I personally think the whole ford solenoid fix for heat soak is a bunch of poppycock and poo.

Believe it or not, GM came out with a technical service bulletin in the mid 80’s and made a service part kit available to address the problem. You guessed it, a ford solenoid. I put several on back then (under warranty) and it never fixed a single one of them. Down in East Texas we sold a bunch of 454 one tons to dairy cattlemen with big trailers and heavy cows. The under hood heat was just too much for that little factory starter solenoid. Especially with those gigantic cast iron manifolds hovering over the starter and increased engine temperatures of the day for emission reasons.

The real problem is the windings inside the factory solenoid. Resistance creates heat but heat also creates resistance. The only thing the ford solenoid does is provide a larger conductor (wire) to the solenoid. When the solenoid is hot, granted it draws more amperage which the larger conductor helps, but the increased resistance in the internal windings creates a weaker magnetic field that is incapable actuating the solenoid. That is until it cools off. If you want to fix it, get a solenoid with better windings.

While this is a common and well known problem, the odds of you actually having this problem are slim in the first place. Even in the 80’s we had very few complaints given the number of vehicles we serviced. Most of those failures these days are due to inherent weaknesses in the aged factory wiring system. Wire your car with a good power distribution system with remote voltage sensing that maintains an operating current of between 13.8 and 14.2 with a modern gear reduction starter and you can sleep well at night.

The ONLY reason I would (and am) using a ford solenoid is so my battery cable is not energized while I am driving down the road as it is the only unprotected (non-fused) circuit in the car. To make it operate you have to turn on the ford solenoid so it will hot up the large battery cable and simultaneously you have to turn on the starter solenoid to engage the starter pinion gear. So that said, yes, you have to split the wire to go to both solenoids as shown in the above referenced circuit.

Again, if you use an old style factory starter you can jumper it and only need one purple wire to the ford solenoid. If you use a mini starter (permanent magnet) you cannot jumper it and will need to split the purple wire to both solenoids.

Hope this helps,

Steve
To each problem exists a solution...now think.

The ZD Nova Page


Edited by 72novaproject on 12-22-11 08:10 AM. Reason for edit: No reason given.

 
65_Impala 
Very Senior Member
Posts: 2333

Reg: 12-29-02
12-22-11 07:47 PM - Post#2171434    
    In response to Charlie57

A mini-starter won't have the same possible heat issues as a full-size starter. Personally, I would install the main wire to the starter ensuring it is properly routed and secured so I could eliminate the Ford solenoid. This eliminates some complexity in the wiring system and keeps it simple. There are many, many, many million GM cars on the road which have power appled to the starter full-time without any issues so it does work.


In reality, the "heat soak" issue is more complex than most people know. There are actually 2 windings inside an "old school" GM solenoid. There is a heavy pull-in winding and a ligher holding winding. The pull-in winding is grounded to the starter motor power terminal and the holding winding is grounded to the solenoid body. When you power the S terminal, both windings get power and draw current. Once the solenoid kicks-in, it will provide 12V to the starter motor and the pull-in winding then has 12V on both sides of it and is effectively removed from the circuit. The pull-in winding is a heavy guage winding which makes the GM starters very hard electrically to engage. It causes the solenoid to draw a high current, easily around 20 to 30 amps, until the solenoid is engaged. The holding winding is a much smaller guage wire and draws much less current once the solenoid is engaged.

On an older, weaker power system, the wiring from the battery, through the key, neutral switch and finally to the starter S terminal, has a fair bit of resistance. It can possibly have a resistance that is approaching the same level as both solenoid windings together. In other words, the start circuit wiring is so weak it can't provide the current needed to energize the solenoid without a major voltage drop measured at S terminal.

When cold, the solenoid will have a low resistance and draw enough current to generate a large enough magnetic field to energize. This start attempt will cause a large voltage drop at the S terminal, possibly drawing the voltage down to 6 or 7 volts at the S terminal. However, the solenoid resistance is low and the reason the voltage dips is because it's drawing lots of current through the start circuit wiring. Remember, the magnetic field is produced by the current and not the voltage.

When hot, the solenoid will have a higher resistance and draws less current so it doesn't generate a large enough magnetic field to energize. There will actually be a lower voltage drop at the S terminal, possibly drawing the voltage down to around 7 - 8 volts at the S terminal. Remember, the wire connected to the S terminal didn't change so the only way to raise the voltage at the S terminal is to draw less current. Hotter windings in the solenoid have a higher resistance so they will draw less current from the same source.

The Ford solenoid fixes the problem by raising the voltage on the S terminal enough that the current is always high enough to engage the solenoid. You could also install new wiring in the car so it doesn't have as high a voltage drop. You could also install a mini-starter that doesn't have as high a current requirement to start.





 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-23-11 08:35 AM - Post#2171553    
    In response to 65_Impala

Nice write up 65_Impala! Very informative and a good read.

At the dealership the starter solenoid was what they called a “non field serviceable part” so I have never dug into the internal workings of it. Back in the day, when we actually fixed things instead of just replaced parts, we would flip over the copper washer and clean the contact points on the studs, but the windings, I never studied.

Speaking of the positive battery cable and the ford solenoid, I agree that to keep it simple is the best approach. However, my cable will run under the car from the front to the back. Even the remote possibility of a direct short on that cable terrifies me.

I would also like to say that the positive battery cable only needs to provide enough amperage to turn the starter motor which shouldn’t draw more than 200 amps (don’t quote me on that) even when it is close to failing. I can’t seem to find my conductor size chart just now but I was surprised to find that the starter motor under a well maintained condition should operate reliably with as little as a 6 gauge conductor. That is pretty small and I would never do it but some guys use 1/0 or even 2/0 cables which is way overkill. I am considering the use of a 2 gauge cable (since it is only for the starter) and routing it inside the car rather than under. Your thoughts?

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
someotherguy 
Moderator
Posts: 25571
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
12-23-11 04:44 PM - Post#2171697    
    In response to 72novaproject

A little bit of trivia, your typical pinball "flipper" coil operates under the same 2-winding principle - high power flip, and low power hold. A common problem in the older design is a failure of the contacts that break the connection for the high power side; the contacts get pitted...like a set of old ignition points. Funny, some of the parallels between the two worlds.

I'll second the recommendation of the mini-starter; even the GM OEM unit is an excellent piece with lower overall current draw and higher cranking power. They're great little units and can easily turn over even a large cube/high compression engine. Something to consider.

They can offer some needed exhaust clearance in some scenarios too; for example, I like using them on lowered trucks keeping stock exhaust with a raised Y-pipe. You can't get the full size starter in/out without dropping a raised Y-pipe. The mini makes the job a snap. When converting from a full size to an OEM mini be 100% sure to get the correct bolts for it, which are shorter than the typical GM starter bolts everybody has a dozen of.



Richard
94 C2500LD / 94 C1500 / 06 300C SRT8
Check out my truck shop projects


 
72novaproject 
Senior Member
Posts: 3210
72novaproject
Age: 58
Loc: D/FW Texas
Reg: 02-18-03
12-27-11 05:30 AM - Post#2172734    
    In response to someotherguy

  • someotherguy Said:
A little bit of trivia, your typical pinball "flipper" coil operates under the same 2-winding principle - high power flip, and low power hold.



I am old enough that a night out to the arcade was pinball and billiards. You couldn’t walk into a 7-11 that didn’t have a tube tester and a pinball machine. When the pinball machine was broke the flipper would quiver but not flip. I assume now that the problem was only the low power coil was working. Interesting. Thanks for that.

My son has the GM OEM mini starter and it works great. My other son has a Summit Racing mini (Hitachi I think) and I am not too impressed with it.

Steve
To each problem exists a solution...now think.

The ZD Nova Page


 
someotherguy 
Moderator
Posts: 25571
someotherguy
Age: 44
Loc: Texas
Reg: 08-01-03
12-27-11 12:19 PM - Post#2172863    
    In response to 72novaproject

Steve not to sidetrack too much but usually on pinball machines the coils last forever (unless they get stuck "on" due to a switch failure, etc. and melt down) but the devices around them fail. The old design routes the high power through a set of contact points ("end of stroke" switch) that makes the "flip" winding circuit until the flipper travel reaches the end and spreads the switch, breaking the circuit so only the "hold" winding is used. Newer machines do this all in solid-state electronics to eliminate the wear and tear on the switch. (another automotive parallel: points to electronic ignition)

Back to the starters, the GM minis get swapped out a lot when they eventually wear out because people find out they're expensive to replace and often expensive to rebuild when compared to a fullsize starter. However they work very well for a long time and solve many heat and space limitation problems, I think they're a great option for guys looking for a strong starter with OEM quality.

OK, I'll quit preaching now.

Richard
94 C2500LD / 94 C1500 / 06 300C SRT8
Check out my truck shop projects


 
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