Question about 1985 Ford F150

2 Answers

My 1985 f150 w/351 windsor will start and run for quit a will then shutdown. i think im losing power at the coil. i jumpered it to the battery and it started but shut off after i removed the jumper wire.

Posted by on

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 395 Answers

The ignition systems on vehicles with points in the distributor to switch the coil had a Ballast Resistor either near the coil (in a ceramic block) or incorporated into the wiring harness. The value is about 0.5 ohm cold, and will drop the battery voltage down from 12 V to around 7-8 V and is used to limit the current through the points to prevent premature burn out. The coil in this setup is stamped on the bottom “Use with Resistor”. With this type of system, when the key was turned to start, the Ballast Resistor was bypassed to give maximum voltage to the coil and hence good spark to the plugs when the battery voltage was being pulled down by the high current draw of the starter
Once the key was returned to the run position the resistor was back in circuit. If the Ballast Resistor has a high resistance, the engine will start but not continue to run for long because there is little or no power to the coil. Your test of jumpering the battery direct to the coil tends to indicate this. When the Ballast Resistor goes open circuit the engine will start but not continue to run at all. First make sure the low voltage connections to the coil are clean and tight.
If the Ballast Resistor is easily visible adjacent to the coil, then a replacement from an auto parts retailer should solve the problem. If the Ballast Resistor is incorporated into the wiring harness, you may need the help of an auto electrician to fix the problem

Posted on Sep 13, 2010

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 707 Answers

The altinator sounds to be unservicable...Hope this helps.

Posted on Sep 13, 2010

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Im having problems I think the coil went out im not site it wont start or charge do u think I messed something up or do u think it can bet fixed


Jump start it then while its running remove battery cable if it dies you need a new alternator and or battery

Nov 05, 2014 | Cars & Trucks

1 Answer

Replace coil pack


if you mean it will only spin over and run with a jumper check battery & cables--if it shuts off once jumper disconnected shorted battery or bad alternator---if battery more than 3 years old recommend replacement than have reputable shop check charging system (not school kid working at autozone)--or buy yourself a digital voltmeter--12.5VOLTS fully charged battery engine off 13.5 to 14.8 VOLTS engine running alt. good

Aug 29, 2013 | Mazda B2300 Cars & Trucks

1 Answer

Losing power and dying.


Yes it could be the coil or a number of other electrical components.
You would need to figure out if you have lost spark to the plugs or fuel pressure when the engine quits. It could be a relay, the fuel pump, the coil or igniter, or a long list of other things.

May 04, 2013 | 1985 Nissan Pickup

1 Answer

Truck wont start


If the solenoid is clicking, the usual causes are a faulty solenoid, low battery voltage, bad connections, or a faulty starter.
A dead cell in the battery will do it too.
Can you use jumper cables to power the starter directly ?
It takes at least 10 volts to activate that solenoid.

Jul 05, 2012 | 1985 Ford F150

1 Answer

I tried to start and all power goes out then I Disconnect positive and re connect there is power but it wont even click over and power goes out again


Your description does not rule out a bad battery. Make sure the cable connections are clean and connected correctly. Assuming this is all good check the voltage with a DC volt meter. A fully charged battery should test 12.85 Volts. If it is very near 12 or lower it is a week battery. With jumper cables or other means to get good voltage try and start it again. If is start you have a bad or week battery. If you get it to run check the voltage again while it is running. The meter should now read 13.5 -14.0 volts. If not above 13 volts it is not charging properly causing the battery to run down.....................

Feb 10, 2012 | 1985 Dodge Ramcharger

1 Answer

Cut all the wires in the dash board and cant get it to start again im makeing a demo car out of it so i was trying to wire it to a push botton


Talking about the starter? GM has the solenoid built into the starter, all you have to do is run a wire from the battery to the pushbutton and then to the small terminal on the starter. Also, on the HEI ignition(coil in distributor cap), you can run a wire from the battery to a rocker or toggle switch and then to the end terminal on the coil. Big wire on alternator goes to battery, but the other two I can't remember. One goes to switch and one doesn't matter or can be hooked to the big wire maybe, I think the worst is you cut the switch off but it keeps running. You might need to do something to that choke. Supposed to have power to that wire on the round thing to heat it up and make it open up right, depends on how it runs maybe. Have fun.

Jul 23, 2009 | 1985 Oldsmobile Cutlass Supreme

2 Answers

85 zx wont keep running.


i would look to the ignition coil leave it running and if it gets hot it could be the problem also there is a resistor underneath the coil same thing with that hope this helps regards Jim

Apr 04, 2009 | 1985 Nissan 300ZX

1 Answer

Ford 300 -starts, but quits when you let go of the starter


With the ignition turned on, measure the voltage on the coil + terminal, it should be 8 to 12 volts, if there is nothing or very low ( ie 2 - 3 volts) then I would suspect the ballast resistor, )which may be part of the wiring from the key switch to the ignitionpack or coil.)

Nov 04, 2008 | 1985 Ford F150

1 Answer

1979 cj7 258 ci


Check and make sure your not losing the 12 volts to the coil in the run position off the ignition switch.

Sep 25, 2008 | 1985 Jeep CJ7

Not finding what you are looking for?
Cars & Trucks Logo

493 people viewed this question

Ask a Question

Usually answered in minutes!

Top Ford Experts

yadayada
yadayada

Level 3 Expert

75822 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

fordexpert

Level 3 Expert

5501 Answers

Are you a Ford Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...