87 4.9 300 won’t start

[Mhfco6]

Hey guys need some help here. After jump starting my truck the starter solenoid started smoking and stuck causing the truck to keep trying to start. I pulled the Negative terminal and got a new solenoid. Now the truck won’t start. I thought it was ignition switch so I pulled the steering wheel and don’t find anything out of place. Rod on the column was still moving and ignition switch is still good. I have power at the small terminal on the solenoid and starter will engage if the 2 big lugs on the solenoid are jumped but still won’t start with the key. Any ideas?

 

[RonD]

So starter motor is spinning the engine?

If so do 50/50 test
Spray fuel into the engine, gasoline, quick starter(ether), carb cleaner, brake cleaner, ect............
Try to start
If it starts and dies, then you have a fuel system issue
If it doesn't start/fire its a spark issue
50/50 no guessing

EDIT:
reread post
Starter relay on inner fender can have 2 smaller terminals, one with the "S" is for activating it to start engine
Other thing needed to activate it is a GROUND, metal base of relay must have a good ground to inner fender to work
It should "click" when 12v is applied to "S" terminal, if not its not grounded or new relay is bad

If you jump 12v to "S" post relay should "click" closed and starter motor should activate
If that happens then problem of no Key Start will be in the red/blue wire hooked to "S" post
Could be Neutral switch preventing the 12v from ignition switch from getting to "S" post

"Starter solenoid" is an older term for starter relay

And just as a heads up
Original issue of jump starting and melted starter relay could be the positive battery cable to relay is corroded or cable from relay to starter motor is, or Starter motor itself
Starter motors require about 60-75amps to turn the engine over, thats why those cables and the main Ground cable are so large
When there are bad connections or corrosion inside cables they have to draw more amps and HEAT UP
Starter motors can do the same at end of life
So melted starter relay could be a sign of another issue

And maybe that's why you needed the jump start in the first place, your battery was fine, just not enough AMPs for the bad connections, double batteries doubled the AMPs and ALSO the HEAT that could be generated with twice the available AMPs
These types of starter relays are usually rated for 80-100amps, above that and their internal contacts can be "welded" together, which is what you described, "starter solenoid stuck on"

 

[Mhfco6]

So starter motor is spinning the engine?

If so do 50/50 test
Spray fuel into the engine, gasoline, quick starter(ether), carb cleaner, brake cleaner, ect............
Try to start
If it starts and dies, then you have a fuel system issue
If it doesn't start/fire its a spark issue
50/50 no guessing

EDIT:
reread post
Starter relay on inner fender can have 2 smaller terminals, one with the "S" is for activating it to start engine
Other thing needed to activate it is a GROUND, metal base of relay must have a good ground to inner fender to work
It should "click" when 12v is applied to "S" terminal, if not its not grounded or new relay is bad

If you jump 12v to "S" post relay should "click" closed and starter motor should activate
If that happens then problem of no Key Start will be in the red/blue wire hooked to "S" post
Could be Neutral switch preventing the 12v from ignition switch from getting to "S" post

"Starter solenoid" is an older term for starter relay

And just as a heads up
Original issue of jump starting and melted starter relay could be the positive battery cable to relay is corroded or cable from relay to starter motor is, or Starter motor itself
Starter motors require about 60-75amps to turn the engine over, thats why those cables and the main Ground cable are so large
When there are bad connections or corrosion inside cables they have to draw more amps and HEAT UP
Starter motors can do the same at end of life
So melted starter relay could be a sign of another issue

And maybe that's why you needed the jump start in the first place, your battery was fine, just not enough AMPs for the bad connections, double batteries doubled the AMPs and ALSO the HEAT that could be generated with twice the available AMPs
These types of starter relays are usually rated for 80-100amps, above that and their internal contacts can be "welded" together, which is what you described, "starter solenoid stuck on"

Thanks Ron, I always appreciate your knowledge. I grounded the solenoid at the “I” post and applied 12v to the “s” post and nothing. Truck has always started without the clutch pushed in so maybe a neutral safety issue?

 

[RonD]

"I" post is NOT USED, its actually 12volts when relay is ON, so TAKE THAT GROUND WIRE OFF!!!!

The metal base of the relay needs to be grounded, yours is, I can see the bolt

AFTER you remove, what looks like a white wire from the "I" post
Remove the red/blue wire from the "S" post
Use a jumper wire from battery positive to the "S" post, just need to touch it not secure it, relay should "click" and starter should activate, if not then new relay is bad

If Relay works with jumper then your problem is the red/blue wire doesn't have full 12volts with key turned to START

 

[Mhfco6]

"I" post is NOT USED, its actually 12volts when relay is ON, so TAKE THAT GROUND WIRE OFF!!!!

The metal base of the relay needs to be grounded, yours is, I can see the bolt

AFTER you remove, what looks like a white wire from the "I" post
Remove the red/blue wire from the "S" post
Use a jumper wire from battery positive to the "S" post, just need to touch it not secure it, relay should "click" and starter should activate, if not then new relay is bad

If Relay works with jumper then your problem is the red/blue wire doesn't have full 12volts with key turned to START

Got it, I’ll remove the white wire attached to “I” post. Solenoid does not do anything when 12v is applied to the “s” post. I’ll get a 3rd new solenoid and let you know what happens. Thanks!

 

[RonD]

"I" post was used in the old days for single coil with distributor engines
These ignition coils would run hot and burn out every few years
So car makers started putting a resistor wire or ballast resistor on the 12volt coil positive(+) connection, to lower the running voltage(14volts) down to 8 or 9volts and coils would last for many years
But....................

12v battery voltage drops down to 9 or 10volts when starter motor is activated, so thru the resistor, the coil only had 4 or 5volts, very very WEAK spark with volts that low, especially trying to start a COLD engine, lol
So the "I"(ignition) post was added, it has battery voltage, 9-10volts, when relay is activated, "I" post wire connected to Coil + terminal
A diode was usually used in the "I" post wire, so the engine running 8-9volts at coil + wouldn't back feed thru to relay

 

[Poppa_R]

Hey guys need some help here. After jump starting my truck the starter solenoid started smoking and stuck causing the truck to keep trying to start. I pulled the Negative terminal and got a new solenoid. Now the truck won’t start. I thought it was ignition switch so I pulled the steering wheel and don’t find anything out of place. Rod on the column was still moving and ignition switch is still good. I have power at the small terminal on the solenoid and starter will engage if the 2 big lugs on the solenoid are jumped but still won’t start with the key. Any ideas?

Sounds like the solenoid magnet is not working at all which could happen if it came with the new starter, or the solenoid is not grounded properly

 

[franklin2]

I am betting he forgot a wire when he replaced the solenoid. There should be a smaller wire bolted to the large terminal on the solenoid that goes to the battery +. If your whole truck seems dead, this is definitely what the problem is. This smaller wire feeds 12v to the whole truck, except the starter.

If your headlights and other various things work when you turn the key, then my idea will not be the problem.

 

[Mhfco6]

I am betting he forgot a wire when he replaced the solenoid. There should be a smaller wire bolted to the large terminal on the solenoid that goes to the battery +. If your whole truck seems dead, this is definitely what the problem is. This smaller wire feeds 12v to the whole truck, except the starter.

If your headlights and other various things work when you turn the key, then my idea will not be the problem.

Headlights, dash lights etc all still work. But no start. Starter was removed along with wire from solenoid to starter and bench tested okay.

 

[rusty ol ranger]

IIRC there is a fusiable link on the little wire that runs to the solenoid. Check that to see if its burned or broke

 

[franklin2]

IIRC there is a fusiable link on the little wire that runs to the solenoid. Check that to see if its burned or broke

But his headlights and various other things would not work if it was burnt in two.

 

[rusty ol ranger]

But his headlights and various other things would not work if it was burnt in two.

You sure?

I know its not exactly the same but ive had issues with that wire on my 77 and everything works but the starter/solenoid

 

[RonD]

Yes, there is a wire with fusible link on the starter relays "battery post", along with all the other wires on that one post, it is the 12v distribution point for the whole vehicle
In any case that one wire feeds 12volt to ignition switch, if it was blown then no dash lights with key on, and no starter relay activation with key turned to START
So could be the issue, but as said there would be other symptoms like no dash lights with key on

 

[rusty ol ranger]

Yes, there is a wire with fusible link on the starter relays "battery post", along with all the other wires on that one post, it is the 12v distribution point for the whole vehicle
In any case that one wire feeds 12volt to ignition switch, if it was blown then no dash lights with key on, and no starter relay activation with key turned to START
So could be the issue, but as said there would be other symptoms like no dash lights with key on

i would still check that wire.

 

[Mhfco6]

Got a new carquest solenoid and truck started right up, crazy! Thanks guys. 2 junk ones were Duralast from AutoZone. Original one that started smoking was Duralast too come to think of it.