87 4.9 300 won’t start

[Mhfco6]

You need to get a Volt Meter

I have one, electrical gremlins aren’t my strong suite. I can wrench all day tho!

 

[Mhfco6]

Took my starter to a local hole in the wall to get rebuilt but the guy wasn’t in the mood, so handed me what looked like the same but bigger starter. Ended up being too big so he tried swapping nose cones but that didn’t work either. He ended up rebuilding my original with the bigger starter parts right in front of my eyes. Truck hasn’t given me any issues for a few weeks. Thanks for everyone’s help.

 

[Mhfco6]

Back to square one.. truck slow cranked and wouldn’t start. Hooked jump box up and it started. Idled for an hour, shut it off and same thing. Any ideas?

Troubleshoot Recap:
Voltage drop no issues
Replaced starter solenoid x3
Had original starter rebuilt
New negative batt terminal
New positive batt terminal lead to solenoid

 

[RobbieD]

I'd be looking again at the battery cables. They can corrode on the inside and not look bad, but not pass enough current.

It sounds like you've replaced the positive (red) cable from the battery positive to the solenoid. If so that would still leave the longer positive cable from the solenoid to the starter as being suspect.

The negative (black) ground cable is just as important. On a lot of older Ford trucks, the ground cable goes from the battery negative to a lug on the frame, then continues on to attach to engine. The frame lug can be corrosion point. Even if you replaced the "negative battery terminal", you still have the current restriction farther down the cable.

If the problem is on the negative cable side, there's a shade-tree test you can do. When the starter is dragging and not starting the engine, take a jumper cable and put one black clamp on the battery negative post, and the other black clamp on the engine block (don't use the red side for anything). If the starter goes back to working normally, you have a bad ground from the starter motor back to battery.

Bad cables can have another symptom tell- moving or wiggling them can temporarily fix the problem, but not permanently.

Good luck!

 

[Mhfco6]

I'd be looking again at the battery cables. They can corrode on the inside and not look bad, but not pass enough current.

It sounds like you've replaced the positive (red) cable from the battery positive to the solenoid. If so that would still leave the longer positive cable from the solenoid to the starter as being suspect.

The negative (black) ground cable is just as important. On a lot of older Ford trucks, the ground cable goes from the battery negative to a lug on the frame, then continues on to attach to engine. The frame lug can be corrosion point. Even if you replaced the "negative battery terminal", you still have the current restriction farther down the cable.

If the problem is on the negative cable side, there's a shade-tree test you can do. When the starter is dragging and not starting the engine, take a jumper cable and put one black clamp on the battery negative post, and the other black clamp on the engine block (don't use the red side for anything). If the starter goes back to working normally, you have a bad ground from the starter motor back to battery.

Bad cables can have another symptom tell- moving or wiggling them can temporarily fix the problem, but not permanently.

Good luck!

Thanks and a Happy Easter! I’ve cleaned the frame lug where the batt negative goes and then it goes from the frame to the intake manifold. Voltage drops from negative battery to frame lug was .4 / Frame lug to manifold was - .8 - Negative batt to starter mounting bolt was 1.04. I was hoping the cables were okay since the voltage drop wasn’t horrible.

 

[franklin2]

You are checking voltage drops, but have you checked what voltage the starter is actually getting while cranking? Also, a 1 volt drop is not very good. If everything else was perfect, that means the best you can get to the starter is 11v. I would put the meter down at the starter lug and the starter housing and get someone to crank it over while you monitor the meter. That is where the rubber meets the road, if the starter is not getting very much voltage, then that would be the reason for the slow crank. You will then have to work your way back, or jump around, checking voltages. I like checking for 12v rather than doing the voltage drop test. But like the voltage drop test, you must check for 12v WHILE CRANKING.

 

[RobbieD]

^^^ Agreed, that your voltage drop readings do not sound good.

A new positive cable for the solenoid-to-starter section isn't that much money, even for a decent one (not just the cheapest one).

On the ground side, you can test that one with a jumper cable, once you're sure that the positive side isn't the problem.

On one hand I hate spending money, but on the other hand I hate it when my truck's not right.

 

[RonD]

Battery should be minimum 12.3volts after sitting overnight, or at least 6 hours
12.8v is new battery, 100% capacity for holding a charge
12.5v is a 3 year old battery, 75%
12.3v is a 5/6 year old battery and time to shop battery sales, close to 50%

12.2v or lower, 50% or less, and its now a failed battery

If you test a battery just after charging it will have a FALSE higher voltage, needs to sit a few hours before you can get an accurate voltage reading


Disable spark, for a No Start
Put volt meter on battery
Crank engine over for 10seconds, you can jump starter relay/solenoid just MAKE SURE trans is in Park or NEUTRAL!!!!
Voltage should not drop lower than 9.75volts, 10.0v to 10.5v is optimal
If it does drop lower than 10v then starter is drawing to many volts/amps from battery because of cables or starter itself
Or battery has failed, see above test

 

[Mhfco6]

I now have changed all the cables. It seems to be better I’ll post up after a while. Thanks guys! As I was bolting up the frame ground it sparked a little each time it hit the metal.

+ battery to solenoid
Solenoid to starter
- battery to frame
Frame to intake manifold.

 

[RonD]

If it sparked that means something in the vehicle was drawing power(assuming positive cable was hooked up)
Things that are on with key off
Computer memory
Radio memory
Keyless entry

Dome light if door was open, lol
Hood light if hood was open(and it had one)
Glove box light

 

[RobbieD]

As I was bolting up the frame ground it sparked a little each time it hit the metal.

Alive! It's ALIVE!

I now have changed all the cables. It seems to be better I’ll post up after a while.

Good! I hope that gets it back right for you.

 

[Mhfco6]

Just want to post an update and let everyone know the truck has been cranking at starting with no issues after the help you all gave. Thank you!

Sometime cranks longer than usual and thinking it may be the HP fuel pump.

Grandpa has a bronco ii I need to go pick up from him now. Am I okay to drive the truck on the highway with the exhaust cut off before the muffler? No back pressure issues?

 

[RonD]

No 4 stroke engine functions well with any back pressure, that's an old MYTH

 

[rusty ol ranger]

Just want to post an update and let everyone know the truck has been cranking at starting with no issues after the help you all gave. Thank you!

Sometime cranks longer than usual and thinking it may be the HP fuel pump.

Grandpa has a bronco ii I need to go pick up from him now. Am I okay to drive the truck on the highway with the exhaust cut off before the muffler? No back pressure issues?

Drive it. Youll be fine. Deaf, but fine.

I drove my 83 300 for months with basically an open header.

 

[Mhfco6]

Drive it. Youll be fine. Deaf, but fine.

I drove my 83 300 for months with basically an open header.

Picked it up yesterday but didn’t take the Ford. I’ve been neglecting this dodge by letting it sit. Washed her up and hit the road. My house is starting to look like a junkyard!