• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

87 4.9 300 won’t start


Mhfco6

Active Member
Firefighter
Joined
Aug 23, 2015
Messages
389
Reaction score
87
Points
28
Location
Virginia
Vehicle Year
1988
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
2.9
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
0
Total Drop
0
Tire Size
235/75/15
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

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,096
Reaction score
8,193
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
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"
 
Last edited:

Mhfco6

Active Member
Firefighter
Joined
Aug 23, 2015
Messages
389
Reaction score
87
Points
28
Location
Virginia
Vehicle Year
1988
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
2.9
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
0
Total Drop
0
Tire Size
235/75/15
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?
 

Attachments

RonD

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,096
Reaction score
8,193
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
"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

Active Member
Firefighter
Joined
Aug 23, 2015
Messages
389
Reaction score
87
Points
28
Location
Virginia
Vehicle Year
1988
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
2.9
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
0
Total Drop
0
Tire Size
235/75/15
"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

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,096
Reaction score
8,193
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
"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
 

r-hindl71

Papa R
Ford Technician
TRS Event Participant
GMRS Radio License
Joined
Aug 26, 2021
Messages
10
Reaction score
13
Points
3
Age
73
Location
Omaha, Nebraska
Vehicle Year
1991
Make / Model
Ford Ranger XLT
Engine Type
4.0 V6
Transmission
Automatic
2WD / 4WD
4WD
Tire Size
235/75R15
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

Well-Known Member
Joined
Dec 24, 2019
Messages
3,281
Reaction score
1,635
Points
113
Location
Virginia
Vehicle Year
1984
Make / Model
Bronco II
Transmission
Manual
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

Active Member
Firefighter
Joined
Aug 23, 2015
Messages
389
Reaction score
87
Points
28
Location
Virginia
Vehicle Year
1988
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
2.9
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
0
Total Drop
0
Tire Size
235/75/15
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

Im a Jeep guy now.
Supporting Member
Joined
Sep 22, 2007
Messages
12,092
Reaction score
7,065
Points
113
Location
Michigan
Vehicle Year
1987
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
177 CID
Transmission
Manual
2WD / 4WD
2WD
My credo
A legend to the old man, a hero to the child...
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

Well-Known Member
Joined
Dec 24, 2019
Messages
3,281
Reaction score
1,635
Points
113
Location
Virginia
Vehicle Year
1984
Make / Model
Bronco II
Transmission
Manual
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

Im a Jeep guy now.
Supporting Member
Joined
Sep 22, 2007
Messages
12,092
Reaction score
7,065
Points
113
Location
Michigan
Vehicle Year
1987
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
177 CID
Transmission
Manual
2WD / 4WD
2WD
My credo
A legend to the old man, a hero to the child...
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

Official TRS AI
TRS Technical Advisor
Joined
Jun 2, 2012
Messages
25,096
Reaction score
8,193
Points
113
Location
canada
Vehicle Year
1994
Make / Model
Ford
Transmission
Manual
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

Im a Jeep guy now.
Supporting Member
Joined
Sep 22, 2007
Messages
12,092
Reaction score
7,065
Points
113
Location
Michigan
Vehicle Year
1987
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
177 CID
Transmission
Manual
2WD / 4WD
2WD
My credo
A legend to the old man, a hero to the child...
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

Active Member
Firefighter
Joined
Aug 23, 2015
Messages
389
Reaction score
87
Points
28
Location
Virginia
Vehicle Year
1988
Make / Model
Ford
Engine Type
2.9 V6
Engine Size
2.9
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
0
Total Drop
0
Tire Size
235/75/15
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.
 

Sponsored Ad


Sponsored Ad

Staff online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Yotaismygame
February Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top