The biggest killer I've seen of Ford starter solenoids is excessive current across the poles. In your case, it seems like you're using a PMGR starter so the current load would be very low so the cause would seem to be either a very poor ground between the solenoid and the chassis or poor quality solenoid(s).

Are you sure the current issue isn't a flaky ignition switch or NSS?

 

Are you sure the current issue isn't a flaky ignition switch or NSS?

I had put in a new ignition switch (ACp?) and a PMGR (Ford M-11000-B51) after I experienced the solenoid fail with the starter stuck-on. That was about February this year, I have put about 1500 miles since, probably a couple dozen of starts until this failure. I feel confident about the grounds.

I had not considered but I'll replace the NSS next, it seems fine and getting pretty wary of any newly made components.

 

Replace your starter with a starter with an integral starter solenoid and fix the problem for good(though replacing the starter becomes more expensive). If you use a starter with an integral solenoid(though you do have to be sure tooth count is the same) then you just use a relay to trigger it and voila! No more horrible factory ford solenoid. I did this myself and for a time I even had the relay mounted using the old solenoid holes before I moved it to be with all my other relays.

 

Got any more reference, would like to consider

 

I take it that "mini starter" means you've already gone to a PMGR starter.

Lot of of wires on that solenoid. But anyway, some years ago I started going to the newer style starter solenoids. Not sure if all those wires would quite go on one of those. You have to watch buying one as the counter folks will try to give you a three terminal version every time. You want a four terminal version. Like this rather pricy one for example. Part No. DY-861 at O'Reilly's if the link doesn't work.

Advance Auto Parts - Down for Maintenance

 

They call it a Glow Plug Module, but it looks like a starter relay. The DY-860 has 4 terminals. Is this it?

DY-860

 

Would buying a solenoid from a Ford dealer parts dept guarantee a genuine oem quality unit?

 

I've experienced 3 starter solenoid failures over my life. First was about 15 years ago, and the last 2 within the last year. The two recent failures have been the Chinese-made Motorcraft solenoids (B6AZ11450B), from Summit.

The first one failed stuck on, keeping my starter engaged. On Sunday the other failed opposite, would not engage the starter, and I eventually had to hotwire it with a pocketknife. I beat the crap out of it, just won't engage, won't make a sound. Nothing obvious. I was in a parade, the car got a bit warm at the end, around 220, so I shut it down and let if fully cool. Went to turn the key and go home.. nothing, knew exactly what it was.

I've got a fair amount of custom wiring going on I guess, pretty standard stuff, a mini-starter, relays for 12v switched power, and 12v constant, and relays for my headlights. 2ga soldered cables, XS Power battery, new 75 amp alt. I feel good about my wiring, though I am pretty inexperienced.

View attachment 849385

What are folks doing these days, is there any quality parts out there, is eliminating the solenoid a worthy endeavor?

I felt guilty after putting one extra wire on the solenoid (headlight relays). Otherwise everything comes off an auxiliary fuse panel.

 

if it's an option, hit the junkyards. i have a stash of old USA made ones. in fact, the one on my car now has a 72 date code, and it's on there because a new one failed in, iirc, three starts.

 

Same here, I have a nice collection of vintage Ford solenoids scavenged from parts cars and the junkyards.

And the garbage solenoids are why I suggest going to a starter mounted solenoid.

He stated he has a Ford Motorsport PMGR starter. The fender solenoid is now a terminal block and a relay to trigger the starter solenoid, mine is wired the same way.

 

I would second @fordguy 's advice. I put a "new" solenoid on my 65 and it worked just fine. Then one day, while cleaning my engine compartment, I went to remove it and while loosening the nut on one of the big lugs to remove the wiring, the plastic housing just crumbled to pieces. Some real quality there.

 

And the garbage solenoids are why I suggest going to a starter mounted solenoid. Its true that even starter mounted units do fail from time to time, but nothing even close the failure rate of the firewall mounted ones. You can even retain a firewall mounted unit if you don't want to use a more modern relay to trigger the starter mounted unit...if you use a firewall mounted solenoid as a relay, it will at the very least have a lot less amperage flowing through it(but to be clear, even used as a relay the firewall mounted unit is still garbage...which is why I always suggest replacing it with a relay when going to a starter mounted unit)

 

View attachment 849385

Seeing this wire "extension" at the left I think it's wise to put some kind of isolation between this and the firewall!!

 

Having that hot post sitting next to the firewall is giving the creeps. That's all unfused mayhem waiting to happen.

 

Curious... what is the green wire you have added to the solenoid "I" terminal?

 

Pretty sure that goes to my 12v switched relay. You can barely see the two relays behind all that wiring.

I felt guilty after putting one extra wire on the solenoid (headlight relays). Otherwise everything comes off an auxiliary fuse panel.

Yeah, I have fused 4 relays on mine, 2 x lead to fuse panels for 12v switched or constant 12v in the cab, and 1 for each headlight. Don't like the extra wiring for sure, but I thought it was reliable and could make it more efficient later.

Seeing this wire "extension" at the left I think it's wise to put some kind of isolation between this and the firewall!!

Agreed, but there's fuses in there, for each relay. I will change that post to a bus bar with a cover eventually, but I just had that post on hand.

CJs(and I am sure many more vendors) sell 157 tooth flywheel starters with solenoids:

https://www.cjponyparts.com/powermaster-starter-powermax-for-157-tooth-flywheel-3-speed-4-speed-5-speed-automatic-289-302-351w/p/STR9162/?year=1967&gclid=CjwKCAjwwo-WBhAMEiwAV4dybfQ6U4tRL1-lU8NOkoeP25xaP13EzEMfOFl6b7gOxLiXM0tFiuTtGBoCXkIQAvD_BwE

Essentially the firewall mounted solenoid is no longer needed, you use a relay triggered off the ignition switch to feed a 14 gauge wire to the small terminal on the starter and your heavy batter cable to the large terminal. Wiring that would normally be fed off the firewall solenoid is instead fed off the relay(though generally you would need to use a bus bar of some type)

I would show you my wiring...but its a lot more involved than the typical vintage mustang wiring using relays and fuse boxes and bus bars....the type of thing you would only be interested in if re-wiring the car from scratch.

I think I am pretty much there already then..? Here's a snap:

 

Perhaps it finally get through that you already HAVE a solenoid ON the starter.

I have no problem with a the old school solenoid on the fender and a PMGR starter installed. I have two trucks in the driveway that Ford saw fit to equip exactly that way at the factory. It surely works.

Much as I like PMGR starters I have to admit their weak point is their solenoids. Local parts stores want as much for one as you can buy the whole starter for online so I buy solenoids online. I keep one for a spare (too many Fords). The failure with them I have experience is when you go to crank up. Nothing. Not a click or anything. Nothing. Nothing. Click. Click. Crank up like nothing was ever wrong. Or something along those lines.

But I too suspect a ground in your case. I no longer trust any ground anywhere unless I have "voltage drop tested" it. Period. I've been bitten too many times. Fine looking cable. Good ends and all. Rotten and corroded green on the inside when cut open. Brand new cable. Someone crimped the hack out of the end. Looked great. Would have worked better if they had stripped the insulation back first though. How can a component like an alternator not be grounded when it is metal. bolted with metal bolts in metal brackets to a cast iron head bolted to a cast iron block with a big fat healthy ground bolted to it? But I've repaired at least three non-charging alternators by adding a discreet ground wire to their case. Trust no ground, no matter how good it might "look".

 

Perhaps it finally get through that you already HAVE a solenoid ON the starter.

I have no problem with a the old school solenoid on the fender and a PMGR starter installed. I have two trucks in the driveway that Ford saw fit to equip exactly that way at the factory. It surely works.

Much as I like PMGR starters I have to admit their weak point is their solenoids. Local parts stores want as much for one as you can buy the whole starter for online so I buy solenoids online. I keep one for a spare (too many Fords). The failure with them I have experience is when you go to crank up. Nothing. Not a click or anything. Nothing. Nothing. Click. Click. Crank up like nothing was ever wrong. Or something along those lines.

But I too suspect a ground in your case. I no longer trust any ground anywhere unless I have "voltage drop tested" it. Period. I've been bitten too many times. Fine looking cable. Good ends and all. Rotten and corroded green on the inside when cut open. Brand new cable. Someone crimped the hack out of the end. Looked great. Would have worked better if they had stripped the insulation back first though. How can a component like an alternator not be grounded when it is metal. bolted with metal bolts in metal brackets to a cast iron head bolted to a cast iron block with a big fat healthy ground bolted to it? But I've repaired at least three non-charging alternators by adding a discreet ground wire to their case. Trust no ground, no matter how good it might "look".

Alright, y'all have shaken my confidence in my grounds and cabling. I will try some voltage drop testing for battery, body, alt, and engine grounds.

 

I have had similar problems with "NEW" solenoids and re-manned stock starters. Mine finally settled down and quit failing when I quit getting replacements at Napa auto parts for new ones that failed, both starters and solenoids.

I had the same problem with re-manned stock starters on my Truck so when the 4th one failed I stole the mini starter out of my mustang and put it on the truck and then had to order an identical one to replace on the mustang. I can't remember who my last supplier of solenoids was/is. I probably should have written that down somewhere but I haven't lost a solenoid since I quit Napa. I think they are Motorcraft but I woluldn't consider any below 25 bucks or so.

 

As you already have the PMGR starter, a relay to replace the fender relay (solenoid) would be wired the same. I would move your high-amp connections to a studded rubber Lord mount, and send a small feed wire to the new relay terminal 30, the starter wire and coil wire out on 87, signal ground wire on 85, and NSS wire on 86. As some relays have internal diodes, the rule-of-thumb is power IN on even-numbered terminals, and OUT on odd ones. This triggers the relay only when the key is in START, NSS is closed, and feeds power to the PMGR starter solenoid and coil for starting.

If your GRN wire is for switched-power relays, it is being fed by the resisted coil power. Typically the GRN switched relay signal would come directly from the ignition switch (before the PINK resistor wire or other ballast), as it's a very small load. The GRN wire is not a deal-breaker as most Bosch-style relays will hold down to very low and pick-up at ±9V, but any momentary power glitch may not re-energize the relays with resisted coil power voltage down around 6V. Food for thought.

 

FWIW, people that install parts that DO work tend not to bother leaving reviews. I've purchased and installed a LOT of parts in my time and I don't recall every going back to leave a single positive review ever. Not once.
FWIW I have seen folks overtorque the nuts on the big solenoid posts and break them right out of the solenoid. Not a problem I would blame the part for.

 

LOL. Few people post a positive review when they DON'T get food poisoning at Chipotle, either, but.......

 

So far I was lucky... until yesterday the "I" terminal got stuck on my other classic. Engine kept running even with the key removed. Had to pull the "I" wire to shot her down. Well, at least better than having the starter engaged all the time. I heard good things about the Stancor 586 type. Needs a bit of adaption and is far from concours, but not a big deal for me at the other classic.
Anybody tried this type?

 

I heard good things about the Stancor 586 type.

The Stancor 586 family are units are also commonly known as "contactors" when they get that large. If you search with that term, you will find additional usable and unusable options. If you can obtain an original one (not imported fake), then it should do well to replace the fender relay (solenoid) for the starter only. Most of our starters range from 1100 to 1500 watts.

There are several versions in the 586 family, but none of them contain a second set of smaller contacts for the ignition coil (equivalent "I" terminal to boost coil voltage during cranking). If your ignition is not stock and does not use the original fat pink resistor wire or other ballast resistor, you're good. But if it does, low-battery starts could be problematic without other workarounds. FWIW

 

Alright, I dunno anymore.. I put in a new Motorcraft solenoid on the fender, it started just fine, but I only started it once and left it at that.

I went to start today.. doesn't start, seems to be in the same exact condition as when I started this thread...

When I turn the key, I get nothing, no sounds/clicks, etc. My dash lights, headlights, tach, clock, turn signals, etc all DO work. Battery seems fine at 12.8v.

Now, if I take a cable and touch the positive side post of the solenoid, to the starter side, it WILL turn over. And if the key is ON, it will start normally and run fine. I have the PMGR starter, so starter cable is already on the positive side.

Essentially:

 

Your ignition switch is the same in all these cases.... I would suspect the ignition switch start position is not working reliably.

 

Look for power at the S terminal plug while trying to crank it, if none, then go with @Rufus68 idea.
Just curious, what is the green wire from the I terminal powering?

 

So, my wire colors aren't indicative of anything really in this sense. The green wire feeds a fused relay hidden just under the solenoid if you look very close, I use that for 12v switched power.

The thinner blue wire you see is the ground for the relay, grounded at the same spot as the solenoid to fender. And the thinner red wire is the lead that runs back through my firewall, to a fuse block, which I have my tach, clock, etc on.

I did disconnect all that for troubleshooting, leaving just starter cables, coil and ignition wires.

Guess I am looking at my ignition switch next! That's a new ignition switch I've had for months. Thanks guys

 

Where did you get the switch from?

 

Oh, duh.. it's a Scott Drake unit

 

IGNITION SWITCH - #11572-2B - National Parts Depot

Buy part #11572-2B IGNITION SWITCH for your classic vehicle from National Parts Depot. Free shipping on orders over $300, fast delivery & everyday low pricing! Order now!

www.npdlink.com

 

For those wanting something a bit more "heavy duty" (and not needing an ignition coil bypass circuit), THIS SOLENOID should do the trick. Note that the additional "small" terminal is a ground. This makes for a nice "safety device" when wired to a hidden reed switch, kill switch, clutch interlock switch, etc., to require completion of the circuit in order to crank the engine.