Mechanics

FORD F-100 STARTER PROBLEM

1979 Ford F-100 • 150,000 miles

Starter stays engaged after truck starts
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Kermdog714
February 9, 2013.



Bang on the starter relay if it stops replace the relay-continues test the ignition switch


Rasmataz
Feb 9, 2013.
OK

WE GOT A FEW POSSIBILITIES. IF THE STARTER IS "UNDER POWER" WHILE ENGAGED

1) THE SOLENOID IS HUNG UP. INTERNALLY, THE PLATE THAT THE ELECTROMAGNET PULLS ON, IS STICKING (OR HAS SORTA WELDED ITSELF TO THE OTHER PLATE).A POSSIBLE WAY TO SEE IF THIS IS THE CASE, GIVE THE SOLENOID A "WHACK" WHEN IT HANGS UP. THEN GET YOU A NEW ONE!

2) "S" WIREON "S" TERMINAL MAY BE CONSTANTLY POWERED

"S" WIRE CAN BE REMOVED FROM THE SOLENOID AND MAY STOP THE CONSTANT CRANKING

. IF IT DOES STOP IT

WHILE YOU HAVE "S" WIRE OFF---TEST IT WITH A VOLTMETER OR TEST LIGHT----IT SHOULD ONLY HAVE 12 VOLTS WHEN YOU TURN THE KEY TO "START"

IT SHOULD DIE--WHEN YOU RELEASE THE KEY

SOMETIMES PEOPLE TIE INTO THE WIRE (I DON'T KNOW WHY!) TO HOOK UP ACCESSORIES AND SUCH

SOMETIMES THE WIRE MIGHT "RUB" OR TOUCH ANOTHER WIRE THAT IS "HOT" ALL OF THE TIME

SOMETIMES PEOPLE GET "S" AND "I" WIRES "SWAPPED" ON THE SOLENOID

"I" IS FOR THE COIL----AS SOON AS YOU TURN THE KEY TO "ON"----"I" GETS POWER CONSTANTLYSO. IF IT'S ON THE WRONG POST THE SOLENOID WILL ENGAGE----THUS ENGAGING THE STARTER

YOU CAN TEST (AS ABOVE) TO FIGURE OUT WHICH IS "S". OR JUST SWAP 'EM AND SEE WHAT HAPPENS

THE 1ST DIAGRAM I'M SENDING YOU A DIAGRAM FOR MY 1979 JEEP CJ 5WHICH USES A FORD SOLENOID TOO YOUR WIRE COLORS MAY NOT BE THE SAME

THE SECOND DIAGRAM IS JUST FOR GIGGLES. YOURS MAY NOT BE LIKE IT. BUT SIMILAR

LET ME KNOW WHAT FIXED IT!

THE MEDIC

.


Tiny
CJ MEDEVAC
Feb 9, 2013.
ONE OF THESE IS NICE TO HAVE WHILE TESTING. AND FOR A FUTURE EPISODE, WHEN YOU ARE FREAKING OUT AND HAVE NO TOOLS TO TAKE THE BATTERY LOOSE

THE MEDIC


Tiny
CJ MEDEVAC
Aug 18, 2013.