FE Power Forums
FE Power Forums => Non-FE Discussion Forum => Topic started by: Kevin66 on November 16, 2019, 11:20:33 PM
-
Trying to help my nephew again, on his '66 289 Ranchero. The problem he's having is that the engine begins cranking the instant the key is turned even slightly towards the 'Run' position...nowhere near over to the 'Crank' position...and then it won't stop cranking, even when the key is moved to 'Off'!
What's really puzzling is that everything worked fine for several weeks, and then just appeared one day. The starter (Denso hi-torque mini) was new, as were the battery, cables (including solenoid to starter), solenoid, alternator, regulator and ignition switch. The battery has been kept fully charged. The ignition system is a Pertronix III module in a Ford 289HP distributor, and the recommended Pertronix low-ohm coil. A Pertronix relay routes full 12V power to the coil, just using the factory wiring to activate the relay.
We've tried disconnecting the battery ground cable when this starter run-on happens, and of course the cranking stops immediately. It also stops when the small red/blue wire is removed from the 'S' terminal on the starter solenoid. If we 'jump' the solenoid from the 12V input terminal over to the 'S' terminal...whether with the red/blue wire connected or not...the engine cranks. If the key is in the 'Run' position, the engine will start.
A lot of reading on forums seems to indicate that many people have this same issue, on a multitude of cars and trucks of all years. There does not seem to be any real consensus on solving this problem either. Frequent recommendations are to replace the starter, solenoid, or ignition switch. Yet many posters say the problem has persisted even with these new parts.
With the red/blue wire disconnected from the solenoid 'S' terminal, the engine can't be cranked with the ignition key. With that wire back on, and the brown 'I' terminal wire (ignition) disconnected, the engine won't crank until the key is moved all the way to the 'Crank' position. It stops cranking when the key is moved back to 'Off'. When the red/blue wire and the brown wire are swapped on the solenoid, the engine starts cranking in the run position, and won't stop.
The ignition switch has been replaced with yet another new one, but no difference. All wiring connected to it other than the factory 3-wire pigtail connector were removed, but still the starter run-on persists. I'm fresh out of ideas here, and would appreciate some input! Thanks if you got this far, and can help.
-
Do you have the wires crossed at the solenoid on the two smaller terminals?
-
After just looking at a new Robbmc mini starter I looked through the wiring diagram they list online. Seems that many times a DIODE is needed on the one solenoid wire to keep from back feeding. If that was installed, then it sounds like it is shorted and not doing its job anymore.
https://www.robbmcperformance.com/products/fordat_starter.html
Go to bottom of page and download the instructions and read carefully. Seems this might be the issue that more people have when they complain about these starters failing.
-
My guess would be a sticking solenoid. You removed power to the starter, and the starter quit spinning. I have had same on the Cougar, a hammer to the solenoid disengaged it. I have had a couple of "functionally impaired" solenoid switches lately that seem to last a few weeks then stick. I cut one apart, the contacts were burned, pitted, looked like they had welded together a few times. Hammer caused them to separate, but burned , pitted contacts , the solenoid was done after a couple months of driving. IMO not a quality part.
-
Do you have the wires crossed at the solenoid on the two smaller terminals?
Thanks for the thought, but no, we don't. The red/blue wire is on the 'S' terminal, and the brown wire is on the 'I' terminal. As I mentioned, we did temporarily swap the two to see what would happen, and it did the same thing...the starter would not stop cranking.
-
My guess would be a sticking solenoid. You removed power to the starter, and the starter quit spinning. I have had same on the Cougar, a hammer to the solenoid disengaged it. I have had a couple of "functionally impaired" solenoid switches lately that seem to last a few weeks then stick. I cut one apart, the contacts were burned, pitted, looked like they had welded together a few times. Hammer caused them to separate, but burned , pitted contacts , the solenoid was done after a couple months of driving. IMO not a quality part.
Well, you could be right, and I guess the solenoid is easy and cheap enough to replace and find out. But I had kind of felt that when the engine would quit cranking if the 'S' terminal wire was removed, then the solenoid was operating properly. Similarly, because the solenoid would engage and crank the engine when a jumper was used between the battery input and the 'S' terminal, but then immediately stop cranking when the jumper connection was broken, that also suggested the solenoid was working as intended...??
-
After just looking at a new Robbmc mini starter I looked through the wiring diagram they list online. Seems that many times a DIODE is needed on the one solenoid wire to keep from back feeding. If that was installed, then it sounds like it is shorted and not doing its job anymore.
https://www.robbmcperformance.com/products/fordat_starter.html
Go to bottom of page and download the instructions and read carefully. Seems this might be the issue that more people have when they complain about these starters failing.
Thanks for that suggestion. Robb's info is very similar to what Powermaster says...NOT to use a jumper on the lower (starter) solenoid. When I looked at the Denso starter though, the jumper was a 'strap', rather than just a wire, and appeared to be OEM?
I see that Robb suggests moving the large starter cable over to the 12V input side of the fender-mounted solenoid, and using a jumper between the old starter cable terminal of that solenoid, and the starter-mounted solenoid's 'S' (start) terminal...rather than putting the diode into the 'I' terminal (brown) wire, and running a jumper from there. Since we're not relying on power coming out of that 'I' terminal to provide a full 12 volts to the coil anymore (Pertronix relay in use), I'm not even sure that the brown 'I' terminal wire is still needed?
I'll look at trying both of Robb's suggestions, in hopes that one might work.
-
The S wire is the relay trigger, the I contact is to supply ignition current during cranking. Use of the I contact is dependent on vehicle wiring. As for starters, I use both kinds without issue. The old Summit and the current Powermaster on the door car only need the large starter current wire. The Summit PMGR on the dragster requires the separate wire from crank to the solenoid. I do not and have never wired any starter other than battery on one side and starter on the other. If you engage the relay then the battery is connected to the starter. If the PMGR starter needs a trigger at it's solenoid to initiate cranking, then that can come from key crank or possibly even shorted at the starter. On the dragster, crank sends current to close the solenoid and connect the battery to the starter and sends current to the starter solenoid to engage the starter action.
Conventional - how my door car with the Powermaster is wired, battery in trunk.
(http://raceabilene.com/misc/StartboxWiringDiagram.jpg)
I see where some people move starter power to the battery and use the relay to trigger the remote
https://www.fullsizebronco.com/threads/how-to-properly-wire-your-pmgr-mini-starter.218409/
I prefer - on the race cars - to have both paths dead unless it's cranking. ESPECIALLY if the battery is in the trunk.
-
With the red/blue wire disconnected from the solenoid 'S' terminal, the engine can't be cranked with the ignition key. With that wire back on, and the brown 'I' terminal wire (ignition) disconnected, the engine won't crank until the key is moved all the way to the 'Crank' position. It stops cranking when the key is moved back to 'Off'.[/i]
Thanks again to all of you for your input. Unfortunately, after looking at or trying each of your suggestions, the problem persists.
Sorry if what I wrote earlier caused any confusion, but apparently I was only half right in the quote above.
When the (brown) wire is removed from the 'I' terminal on the (fender) solenoid, the engine will still start cranking as soon as the key is turned even slightly towards 'Run'. The key does not need to be turned right over to 'Crank'. When the key is moved back to the 'Off' position, the cranking will stop (if that brown wire is left off the 'I' terminal). As you'd expect, there is no starter cranking if the key is moved to the 'Accessory' position either.
This is the pretty much the same as happens when the 'I' terminal wire is attached, except if it is, the engine will not stop cranking when the key is moved back to the 'Off' position...or even if it's removed!
As puzzling as it is to have the starter cranking when you're nowhere near the key's 'Crank' position, there's another issue. Full 12V power is coming through both the red/blue 'S' terminal wire, and the brown 'I' terminal wire when this is going on, even if the brown 'I' terminal wire is not connected to the solenoid. So it is clearly bringing power up to the solenoid, not getting power from the solenoid, as it's supposed to...??
So it would seem that wherever this 12V power is coming from, it's getting into both the 'S' terminal wire, and the 'I' terminal wire, from somewhere near the ignition switch itself. Where from...and how it gets there...is still a mystery!
-
Did you try another/different solenoid? Sometimes it's the easiest things that we overlook.
-
I would remove the existing wires from the key harness("I" and "S") to the solenoid. Using a remote start button, try to operate the solenoid and see if it functions correctly. That would prove the wiring is at fault.
If it stills sticks on crank, then the solenoid is at fault.
-
I would remove the existing wires from the key harness("I" and "S") to the solenoid. Using a remote start button, try to operate the solenoid and see if it functions correctly. That would prove the wiring is at fault.
If it stills sticks on crank, then the solenoid is at fault.
Okay, we've now tried both of these last two suggestions. Disconnecting both the 'S' and 'I' terminal wires, and jumping the solenoid from the battery input to the 'S' terminal, cranks the engine. It stops cranking immediately when the jumper is open. So it looks like the solenoid is doing its job. But just to make sure, the solenoid was replaced. With all wires ('S' & 'I') connected, the engine continues to crank even when the key is returned to the 'Off' position...or removed. So it looks like it has to be a wiring issue...something has gone wrong back by the (new) ignition switch! Now we just have to figure out what!
-
Sure sounds like a funky switch. I know you said it's new, but I've seen plenty of "new" parts be bad out of the box. Do you have the original switch, by chance? You've eliminated the solenoid a couple times and starter is ruled out, so all that remains is wiring from the switch and the switch itself. I have a feeling it's the replacement switch.
-
Why were the parts replaced, solving an issue or just old parts? If they were still working and you still have them i would start putting them back on one at a time starting with the easiest to change first to try to pinpoint the problem.
On another note, just curious what guage the starter cable was.
-
I remember a read somwhere that the new ign switches was junk
-
Why were the parts replaced, solving an issue or just old parts? If they were still working and you still have them i would start putting them back on one at a time starting with the easiest to change first to try to pinpoint the problem.
On another note, just curious what guage the starter cable was.
The car had sat for years outside, exposed to the rains here in the Northwest. Everything under the dash was rusted, so the ignition switched was replaced because of that...and because there was no key for it! The first replacement was a Scott Drake, and the second was a Standard brand. The car started and ran properly for a few weeks with the first one, then began the refusing to stop cranking issue. The second one refused to stop cranking from the get go.
The starter cable is an Accel, and is #2 gauge.
-
Re-reading - I'm with the "bad key switch" crowd. The I terminal is only there to provide power to the ignition (I) during cranking for cars wired that way. Some aren't - my Falcon never used the I terminal as built by Ford. So if a slight turn of the key engages the starter, the trouble IMHO is right there and not elsewhere. My 1993 F-350 has a replacement key switch and while it cranks properly, getting the key in the exact right position to remove the key and not have the chime sounding is tricky. It's a regular thing to open the door and have the chime start sounding. Proper wiggling of the switch housing shuts it up.
-
Re-reading - I'm with the "bad key switch" crowd. The I terminal is only there to provide power to the ignition (I) during cranking for cars wired that way. Some aren't - my Falcon never used the I terminal as built by Ford. So if a slight turn of the key engages the starter, the trouble IMHO is right there and not elsewhere.
Hhhmm? I don't know...yesterday evening we removed the ignition switch. The 3-wire pigtail that presses on over the spade terminals had been replaced too, because at some point it seemed that the 2-wire green/black connector that is fitted over the 'Accessory' post on the switch, had overheated and melted into the original pigtail block some. We removed the butt connectors that spliced the pigtail's 3-wires to the factory wiring, and took it all over to the workbench.
Connecting 12V power to the (battery input) yellow wire, we had power at the red/green 'I' (ignition) wire only with the key over in the 'Run' position, and also in the 'Crank' position. The red/blue 'S' (solenoid) wire had power only while in the 'Crank' position. In my mind, that clears the ignition switch as the cause of the problem.
That was interesting to note, because before removing the ignition switch from the car, we had used a 12V probe light on the 'Accessory' post and some of the wires. When you started to turn the key towards 'Run', there was power immediately in the 'S' and 'I' wires...but no power at the accessory post until the key reached the 'Run' position.
What was also interesting, was that this probe light has a 'red' light for 12V '+' connections, and a 'green' light for use when checking for ground '-' connections. Normally, in order to test for ground, you have to connect the alligator clip on the probe's cable to a 12V source, and touch the point to whatever ground spot you were testing. But in our case, the alligator clip was connected to a chassis ground, and the probe's point was being touched to the 12V source we were investigating. When testing for power on the green/red 'I' wire, as we switched the key back to the 'Off' position, this green 'Ground' light would flash for an instant when the red light shut off. It did not do this when we checked the blue/red 'S' wire, or the accessory post...the red probe light just shut off.
What this momentary green flash means...and what would cause it...I don't know. ???
-
Check your grounds from block to chassis to body. Just a guess but sometimes things will back feed power if the ground isn't sufficient.
-
Re-reading - I'm with the "bad key switch" crowd..if a slight turn of the key engages the starter, the trouble IMHO is right there and not elsewhere.
RESOLVED...finally!
I'd misinterpreted what my nephew told me when he took the ignition switch over to the bench. I thought he'd said he was getting power only to the red/green 'I' terminal wire when the key was in the 'Run' position, and power to both it and the red/blue 'S' terminal wire when in the 'Crank' position.
That was the case when he tested only the ignition switch terminals, without the ignition pigtail connected. Turns out that when the pigtail was in place, both red/green and red/blue wires were powered, indicating there is a short somewhere inside that molded plug in the 'new' pigtail.
So those of you who said "Just 'cause it's new don't mean it works properly!" were right! Yet another new one is on order. Thanks again to all who gave input, and I will remember this lesson!
-
Unfortunately in today's world...................Assume NOTHING!!!