Solenoid / Ultra Tork Starter Solenoids 40200

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Machvince

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Joined
Jul 15, 2018
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Location
France
My Car
73 Mach One Q code
Hello,
I was about to go to my local race (short hill climbing) and my 73 didn't start.
I hear de "buzzz" from the Solenoid. As i had a spare : Ultra Tork Starter Solenoids 40200
I made the change.. but the starter don't stop running, i have to cut the battery ..
Do i have bought the wrong type of solenoid ? (Accel 40200) ?
Any help would be appreciated ..
 

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Wiring is the first thing to check. Easy test is to remove the black wire and see if the engine cranks. If it doesn't then move the yellow capped wire to the black wire side and see if it cranks.

A multimeter is helpful too. One wire will have power only when the key is turned to the crank position, this one is normally placed on the small post on the battery side of the solenoid. The other wire will have voltage when the ignition is in the ON position, if you still have the original ignition in the car this wire may read a reduced voltage.

The standard solenoid works as follows. When power is applied to the S side (the small terminal on the batter side) it closes the switch so that power can go from the large battery terminal to the large starter terminal. In addition power is routed to the small 'I' terminal. The wire on the 'I' terminal is connected to the coil. In the stock ignition system there are two wires providing power to the coil. This "I" wire and a resistor wire that is energized when the key is in the ON position. The 'resistor wire' reduces the voltage to the coil. When cranking the engine the voltage potential drops significantly due to the power draw of the starter. The 'I" wire makes sure the coil gets enough voltage during cranking since it is not a resistor wire.

Often times the car will start even without the "I" wire connected.
 
Thanks. I have done some tests, and for the last one, the engine start but didn''t stop with the key.. I had to remove the wire from the ignition coil... Ouch...
 
By the way, is there anybody who tell me if the Ultra Tork Starter Solenoids 40200 Accel is the good ref for a Q code ?
 
I am confused. Your original post indicates that the starter won't shut off but your latest post indicates the car keeps running.

Do you have a multimeter available?
 
I am confused. Your original post indicates that the starter won't shut off but your latest post indicates the car keeps running.

Do you have a multimeter available?

Thanks for reading me, and sorry, I will try to be more clear.
First the car didn't start (the solenoid was making a buuzzz).
I replace it (Accel 40200, new).
The engine didn't start. I check the wires, and clean the connectors, and try again. And then, The engine start, but didn't stop , even with the key. I had to remowe the wire from the ignition coil. Then the engine stop.
I have check the wiring , an be sure that I have placed de wires on the right sides. Seems ok for me.
As you can see, there are some wire added (it was there when i bought the car).
I wonder it the Accel 40200 is the good one (but if not, i have no idea for the ref of a correct one)
I have a multimeter.

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The "S" terminal on the solenoid should have the Red w/Light Blue stripe wire, it almost looks like you have the Red w/Lt Green stripe on it. Can't tell from the pics, the color is a bit off.
 
Thanks for clarifying.

Here's what I would try next.

Start the car and if it still will not stop running when you turn the key to 'off' try removing both of the small wires from the solenoid.
If the engine stops running leave the wires disconnected and test the two small posts on the solenoid for voltage, there shouldn't be any.
If the engine continues to run with the wires disconnected test for voltage at the two wires you disconnected. Neither should have voltage. Then force the engine off by pulling the main wire from the coil. Test both wires again, they should still both show no voltage. If the one connected to 'I' shows voltage then the problem is not with the solenoid.

What we are doing is confirming that the solenoid is acting as expected or if the ignition is getting power from another source. You can actually do the above voltage tests without starting the engine first but if the problem ends up being intermittent then we might get bad results. So if you want, do the voltage tests before starting the car. Both posts and both wires should show no voltage.


Let us know how it turns out and we can move to the next step.
 
By the way, is there anybody who tell me if the Ultra Tork Starter Solenoids 40200 Accel is the good ref for a Q code ?
Out of 21 reviews on Summit 8 of them have 1 star, most had the same problem that you are having. I would get a Motorcraft solenoid or one from NAPA (MPE ST81SB)
 
The "S" terminal on the solenoid should have the Red w/Light Blue stripe wire, it almost looks like you have the Red w/Lt Green stripe on it. Can't tell from the pics, the color is a bit off.
I am in (as usual) total agreement with HemiKiller, making sure the correct wires are connecting to the Starter Relay's smaller terminals. And even though your photo does not show the "S" and "I" terminal wiring color very clearly, it does show the color of the insulating hood coverings. One is a "blue-ish" looking color, and the other is a "green-ish" looking color. I have found the insulating hood covering colors are correlated to the wire stripe coloring, as shown a little more clearly of this attached photo from a colleague who sent this to me the other week.

Going by the color of the insulating hoods it seems you do have your two Starter Relay smaller wires connected to the correct terminals. It is best to go by the wire coloration, as I have only observed the difference of the terminal insulating hoods when I took note of it, and until recently never bothered to see if there is an intentional difference in there colors or not.

If the Red-Blue Stripe wire (Circuit #32[a]) is correctly connected to the Starter Relay's "S" Terminal, where the wire leads to the Neutral Safety Switch, it will only have power when the Ignition Switch/Key is in the Start/Crank position. Any other time it should have no voltage.

As for the Reg- Starter Relay's Red-Green Stripe wire (Circuit #16), it should be connected to the "I" Terminal. When cranking the engine over that terminal/wire should show cranking battery voltage, which will usually be between 9.6 and 10.5 volts. If you have less than 9.6 volts while cranking you have a battery that needs charging and/or you have one or more connections in the vehicle's wiring that has excess resistance - usually it is a low or failing battery.

When the Ignition Switch/Key is in the Run position the "I" terminal/wire fir Circuit #32 should have aa reduced voltage coming from the resistance wire circuit from the Ignition switch. That reduced voltage should be between 4.5 and 6.9 volts, s it is connected to the Ignition Coil's Positive Primary Terminal (still a Red Green Stripe Wire).

I have attached a relevant section of shop manual snippets for you to refer to. I also have the relevant circuit schematic on my Google Drive (too large to attach to this post). The link to download that schematic is:



If you are getting full battery voltage at the Starter Relay's Circuit 16 wire in the Run position (about 12 - 13 or so volts in the Run position) it is an indication that the wiring has been altered to provide non-resistance voltage reduced current to the Ignition Coil. This is sometimes done when folks replace an oem Ignition Coil with an aftermarket Ignition Coil in the expectation of getting a "hotter" spark at the spark plugs. It is also sometimes done when someone has installed an electronic ignition system along with a new 12 volt Ignition Coil. Please be aware, the oem Ignition Coils are designed to operate at 6 volts, not 12. They will work with 12 volts, but may overheat. Further, a "hotter" spark does not occur just because a higher output Ignition Coil is installed. An Ignition Coil only puts out as much is needed to complete a circuit, to include jumping a spark plug gap. The spark may remain active for longer (a natter of microseconds) when more potetial voltage is coming from an Ignition Coil, but from a practical perspective they won't do much unless you make other changes to the ignition system (widen the spark plug gap, for instance).

The reason I bring up the prior paragraph is because I have seen modified ignition systems where folks will use a relay to provided full battery voltage to an ignition system's primary circuit, and the triggering voltage of the relay may come from a switch voltage source, but said triggering circuit may be provided with voltage that does not necessarily end when the Ignition key is turned off. It can get complicated pretty quickly.

If it looks like your primary ignition system has been altered, you will need to trace down all the related wires, and relay if one is present, and alter the wiring to make certain the trigger voltage to the relay is coming from a circuit that does not fdeed back into a circuit that might be left on when the Ignition Key is put into the Off position. Like I said, it can get complicated in a hurry as there are so many ways an ignition system can have its wiring altered - and not all of then are good, although some of them are done in a correct manner. (using the Stator terminal Circuit #4 (White with Black Stripe wire) from the alternator is a good way to trigger a relay to engage a relay despite being AC current and 1/2 battery/alternator output voltage, as when power is cut to the alternator field circuit, the Stator terminal loses all power - absolutely.

I hope you post the solution to this situation once you find the cause. I am really curious what is afoot.

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I had a similar experience to the OP's. In my case it turned out to be a failing ignition switch. Changed the switch and haven't had a recurrence.
 
Thanks All,
I will test all this Sunday, and give you feedback. I have also ordered a new Motorcraft solenoid.
 
Well, finally it runs... I read all the posts printed , and started carefully. And then I remembered, that when I change the solenoid by the new one, the bolt on the side was to short , and I cannot add all the connectors on it.. As you can see on the picture below, there is a lot of wire.. So when I change the solenoid, i have to remove one nut (the one which in on the side close to the solenoid, battery side).. On the picture the "1" show the side mounted with the 2 nuts. and the "2" show the side with one nuts .. And after checking, this side (in fact the side toward battery... was still loose, event after being tied. I guess that the problem came for that (it means that the screw was moving inside and causing the failure..) on the second pic, you can see the difference of length (between the original left and the Accel). I change the Accel for a motorcraft and it fits well... I hope i'am clear enought.. To summarize, it seems that it was a mecanical failure caused by a clumsy mecanic.. Thanks for all your help, it help me in all the case to understand how does it works. And by the way, I had to change the distributor caps..Seems tired..
 

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