Starter wont stop starting 87 Bronco II

[whocares]

Could it just be that the bendix is hanging in the flywheel? Are the starter bolts tight?

 

[TexCaliBII]

87Bronco2problems,
They are not too hard at all. After getting the plastic covers off you'll see the hole you have to put a paperclip or thin wire into. You turn the ignition switch to run and push the wire into the little hole you'll see and then pull the switch out. Done it a couple times on these rigs. Getting Explorer switches out is another matter entirely........

 

[Txhuntr2]

I’m bringing this back up bc I am having the same issue with my 84 bronco 2.

The first cold start the motor turns, starts and runs fine. The second and subsequent starts, the starter keeps running until I disconnect battery power then it shuts off.

I’ve replaced the starter 3 times and the fender mounted solenoid multiple times. I replaced the ignition switch today. The problem persists. I had a mechanic look at it briefly a while back and he said the starter is pulling way to many amps. I don’t remember how many. His suggestion was to replace the starter but that hasn’t helped. Does anyone have any ideas?

 

[RonD]

Welcome to TRS

Does your starter motor look like this: https://i.ebayimg.com/thumbs/images/g/CmwAAOSw1pZdXV9s/s-l300.jpg
No relay, just 1 larger cable connected
OR

This: https://www.partsgeek.com/assets/dimage/fulln/07605847-1539359.jpg
Has relay, 1 larger cable and 1 smaller wire connected

Should be the first one, no relay on starter
So only the starter relay on the inner fender can send Battery Volts to the starter motor
On the starter relay there are 2 larger posts
One post will have battery positive cable and several other smaller wires connected, this is the Power Distribution post for the whole vehicle
The other larger post can ONLY have 1 cable connected, the one that runs to the starter motor, NO OTHER wires can be on this post

There will be 1 or 2 smaller posts on starter relay, marked "S" and "I"
The "S" post should have the wire from ignition switch connected
When is wire has 12volt the starter relay will activate, so next time starter seems to stay activated pull off this wire, before pulling battery cable, so see if that stops the starter motor
If it does then that wire is shorted to a 12volt wire some where
If it doesn't stop starter then problem is that the starter relay is locking up in the ON position, not releasing when the 12v is removed from "S" post

I am basing this off what you said in your post, about disconnecting battery post stops the starter motor BUT DOES NOT CAUSE ENGINE TO STALL
So after start up, starter stays on, and you pull battery cable off battery, engine stays running but starter stops running
If engine also stalls then there are other possibilities

If engine stalls then alternator is not working, and starter motor was probably off but its GEAR was jammed in ring gear and it couldn't be retracted, which "sounds like" starter is on, but its not, its just being spun by the engine which is not good either, lol, but different type of issue

You can test starter amp draw yourself
Disconnect Coil wire to distributor, so No Start
Put Volt meter on Battery
12.3volts to 12.8volts is a good battery, 12.2volts and under is a 6+ year old battery and time to change it
When starter is activated you should see a 2 volt drop in battery voltage, so if it was 12.5v then should drop to 10.5volts
If it drops to under 10volts then starter is drawing too many amps, or Battery is bad
But that doesn't always mean its a starter motor issue, it can be battery cables and cable to starter that are corroded inside, they don't pass the high amps well so MORE AMPS need to flow
That includes the larger Negative battery cable, not just the positive cables

When engine is running, re-test battery volts, should be 14-14.9volts just after start up
Then 13.5v-13.8v, under 14v, after 5-10minutes of idling
If so Alternator and voltage regulator are working

 

[Txhuntr2]

Thanks for the reply. I wasn’t clear enough in my original post. The battery has recently tested “good”. The starter has one wire to it from the solenoid, which is mounted on the fender wall.

After the first cold start (when everything works as it should), turning the key engages the starter and the engine starts. The problem is that power keeps going to the starter when the key is turned off and the engine is running. When this happens, I turn the key off and the engine stops firing/running, but the starter keeps the motor spinning until I run around and disconnect power. All the current locks the solenoid until I tap it to disengage the connections.

The solenoid is properly wired. have tried pulling off the ignition wire but that doesn’t stop the starter. It may be possible that the solenoid connection has stayed closed by the time I run around to cut power. I will use a screw driver to connect the powered post to the ignition post to see if that operates the starter properly, which would seem to point to or rule out any issues with the ignition switch.

I may try replacing the cable from the solenoid to the starter after that. It’s taped with electrical tape on both ends and got really hot the first time this occurred so maybe it’s old and fried?

Any other suggestions?

 

[Shran]

I had this issue with my old '85 F250... it would not only not stop "starting", it would attempt to start itself at random with the ignition off and in gear. Quite dangerous and very irritating!

The fix was to simply continue replacing the starter solenoid until I got a good one, and after 3-4 junk ones from O'Reilly of multiple brands, I bought a Motorcraft one and had zero issues after that.

 

[RonD]

+1 ^^^

Its the starter relay(solenoid), replace it until you get a good one

It is possible the amp draw is too high which causes the contacts in the relay to "stick" because of the heat build up, as said that can be caused by old corroded cables causing higher amps than relay is spec'ed for

The initial start works because relay is cold, after first start it retains some heat, so on second start it "sticks"

 

[Txhuntr2]

Update. I had NAPA make a new cable for me. It’s the one that goes from the solenoid to the starter. It fixed the issue immediately. I saw that the old cable was fraying and gunked up once I pulled off the electrical tape. Thanks for the advice everyone.

 

[RonD]

Good work

Thanks for the update and THE FIX