engine dont stop when key is off

[bert0427]

I just put a used engine in my 86 ranger it is a 2.9l.. when I turn the key to start it up the engine turns over but once I turn the key in the off position the engine keeps turning until I pull off the ground on the battery. I have replaced the starter relay and it seems to do fine for a couple of times but after that it dose it agin... to me it acts like the relay is stuck and engine will not stop turning over??? any help would be great thanks

 

[RonD]

I assume you mean starter motor doesn't stop turning when key is off

On the starter relay is a smaller wire hooked to the "S" post, this wire Closes/activates the relay.
This wire is connected to the ignition switch and should only have 12volts when key is in the START position, so no 12v in RUN or OFF.

Remove this wire and check its voltage with key in those positions.

If you have 12v on this wire in RUN and STOP then could be ignition switch problem or it is the wrong wire.

If you have upgraded the starter motor to one that has a built-in relay then you have it wired wrong

 

[bert0427]

Wow that is awesome information Thank you so much I will check that in the morning. could this still be the problem even if it dose it randomly or could it be a short ? agin thanks for your input

 

[RonD]

The ignition switch, under the steering column, is a "slide" switch, when you turn the key a metal bar pushes or pulls the "slide" on the ignition switch, this makes and breaks electrical contacts in the switch.
Yes, these can become intermittent.

I would put a test light on the "S" wire so you can see it light up when 12v is on that wire and then move key around and see if it goes off and on when it should

 

[bert0427]

10-4 will do.. I will post tomorrow the results ....... thanks agin

 

[bert0427]

so I used a test light to do the test and here is what happened when the switch was in the run position the light was on... in the off position the the light was off .... so I pulled the starter off, I am going to have it tested and I am going to go ahead and replace the ignition switch. any advice or anything would be awesome thanks for your time .

 

[RonD]

Light should only be on in START position(if hooked to "S" wire) so could have been the switch.
No light in RUN or OFF....or ACC