Won't stop running
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Elder User
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From: Indiana
Won't stop running
Went to the parts store and got some gaskets for my carb and a new starter wire from the starter selonoid ans starter. Put the gaskets on and it started right up. Changed out the starter wire and started it up and when I turned the key to the off postion it keeps running. I don't think that I did anything to the wiring when replaceing the starter wire. Only way to turn it off is pull the connector off the coil. Is the igniton key switch the only thing that will cause this or do I need to check other things out also. I'm not going to mess with it until Tues. evening after work. i have another ignition switch to try and see if it fixes it. If it doesn't what else is there to look at?
I know they say old 300 six's run for ever but I wasn't aware that they meant it in that way. LOL!
I know they say old 300 six's run for ever but I wasn't aware that they meant it in that way. LOL!
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From: Virginia
Is this the 77 f100? Do you have two large terminals on the starter relay(solenoid) and two small terminals?
If you have two small terminals, they should be labeled "s" and "i". The "s" shoudl have the red/blue wire on it. It probably does since it does start. Make sure the large starter wire goes to the large terminal near the small "i" terminal, and the battery + wire goes to the large terminal next to the "s" terminal.
If you have two small terminals, they should be labeled "s" and "i". The "s" shoudl have the red/blue wire on it. It probably does since it does start. Make sure the large starter wire goes to the large terminal near the small "i" terminal, and the battery + wire goes to the large terminal next to the "s" terminal.
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From: Indiana
Yes it is the 77 f100. Sorry I didn't add that. I only changed one wire and didn't do anything to any of the other wires. Yes I do have 2 large and 2 small connections. Am going out to work on it now and will reply back if I find out what is wrong with it.
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From: Indiana
Well I figured it out. It wasn't the ignition switch after all. I poped the hood and started working on replaceing the intake / exhaust gasket. I had discounted the negative cable over night to keep my battery from draining. I thought what the heck, I stopped what I was doing and see if it was still doing the same thing as yesterday. As soon as I touched the negative cable to the negative post I heard a pop or electrical snap sound inside the engine compartment. I tracked it down to the inside of the distributor cap. If I unhooked the coil connection it wouldn't do it. I tried disconnecting the brown wire on the starter side of the starter solenoid and it wouldn't do it. I took a small wrench and tapped the starter solenoid and connected the negative wire back up and it has been fine since. What does the brown wire connect to that would cause the engine to continue to run even after the key was shut off? Does the brown wire get it's voltage from the inside of the solenoid?
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From: Virginia
Yes, the brown wire gets it's 12 volts from inside the solenoid. This is the "i" terminal, which stands for ignition.
When the engine is running, there is a resistance wire in the coil + wire that runs to the ignition switch. If you look at the coil + connection, you should also find the brown wire that runs to the solenoid. What this does is put a full 12 volts on the coil + during cranking, to bypass the resistance wire and give a hotter spark for easier starting.
Your contact in the solenoid got stuck, so it was supplying 12 volts to the coil + at all times, which is the reason it would not cut off. That is why I was asking about the wiring over there, but I never would have thought it would stick like that. Good catch.
When the engine is running, there is a resistance wire in the coil + wire that runs to the ignition switch. If you look at the coil + connection, you should also find the brown wire that runs to the solenoid. What this does is put a full 12 volts on the coil + during cranking, to bypass the resistance wire and give a hotter spark for easier starting.
Your contact in the solenoid got stuck, so it was supplying 12 volts to the coil + at all times, which is the reason it would not cut off. That is why I was asking about the wiring over there, but I never would have thought it would stick like that. Good catch.
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From: Indiana
Put my gaskets on, did a few checks and realized the vaccum advance wasn't working. Got it to work and it runs much better. Took a drive to the gas station and on the way back the engine stops running for about 5 seconds or so and then starts running again. An extremely loud backfire happens and blows my muffler apart. I got the truck home and shut it off. I know that when the motor died it had to be something electrical. Could it be the starter solenoid causeing it to do this or when it got stuck it may have damaged something due to the full voltage going thru it constantly. I have an extra starter solenoid to put on and try. Loaned out my extra ignition module to try changing it see if that helps also.
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From: Easton,Ks
Originally Posted by Ranger GT2
Took a drive to the gas station and on the way back the engine stops running for about 5 seconds or so and then starts running again. An extremely loud backfire happens and blows my muffler apart. I got the truck home and shut it off. I know that when the motor died it had to be something electrical. Could it be the starter solenoid causeing it to do this or when it got stuck it may have damaged something due to the full voltage going thru it constantly.
If the one of the smaller wires on the battery side of the starter solenoid is loose or burnt it may cause this or the ignition switch also cause this.
Of course any loose wires in the ignition system and if the ignition coil over heated it may have a poor connection inside.
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From: Indiana
One thing I thought of today at while at work was the vaccum advance was not working. It had one of the plastic things(can't think of the name) in the line and it wasn't letting any vaccum get to the distributor. I took this out and just hook up the vaccum line directly from the carb to the distributor. The advance works now but could it allow to much vaccum and over advance the timing? Would the ignition module shut down the motor if that occured? Just a thought not sure if that is possible or not.
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From: Easton,Ks
Originally Posted by Ranger GT2
One thing I thought of today at while at work was the vaccum advance was not working. It had one of the plastic things(can't think of the name) in the line and it wasn't letting any vaccum get to the distributor. I took this out and just hook up the vaccum line directly from the carb to the distributor. The advance works now but could it allow to much vaccum and over advance the timing? Would the ignition module shut down the motor if that occured? Just a thought not sure if that is possible or not.
A bad ignition module can shut down the engine but the ignition module does not know what the engines advance is.
The ignition module does change the advance while cranking but after it starts the timing is done by the distributor.
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From: Indiana
Thanks for the clarifaction. I'm working on getting the exhaust fixed now and changing out the starter solenoid. If it does it again I'll start checking connections and wires. Thanks for all your help. You guys are electrical wizards. Do you do this for a living or just for fun? I just love working on the old stuff. Everything is so basic and easier to troubleshoot.
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I got the exhaust fixed and so far it hasn't died any more on me but I haven't drove it very far. I'm just keeping my fingers crossed and hopeing for the best. If not you'll see another post on here. Thanks again for all the help.
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