Engine won't stop running

[fasteddie]

I have an ignition switch that won't kill the engine in the off position. I think the alternator is backfeeding the switch keeping the off position hot when I turn it off. What could I do to clear this up?

 

[dustybumpers]

In the green red tracer wire, coming from the alternator, put a small light bulb. The one for a set of gauges will work. It just sets a load between the alternator and the key. Pulling on the headlight switch and shutting off the key will do the same thing, but you have to remember to shut the lights back off.

 

[BuzzGun79]

Are you sure the ignition switch is good,i would check all ignition circuts with a volt meter or test lite.along with the switch.the switches do wear from use & if you have alot of keys on your ring as well.

 

[fasteddie]

the switch is new. Turns out it was a backfeed from the alternator. I put a diode at the ignition terminalto one of the wires on that terminal and that fixed it.

 

[fasteddie]

Now we have a new AOD transmission with 3rd and 4th gear burned up. It's a B&W the owner bought 6 years ago. All new. Something stuck in the valve body is what the trans. shop tells us. I guess it's back to the drawing board. When he gets some more money. Anybody have this happen to them. We are shocked this new transmission did this. This makes no sense. Maybe some of you could shed some light on this.

 

[mtflat]

All mine use 3 pedals - sorry i can't be of help - just don't know auto trans at all. Is this behind a flathead? That would make a difference on who I could recommend for help.

 

[fasteddie]

No, it's all custom. It has a 351W tricked out. A rebuild cost as much as a new trans. Any advise. Money is tight at this point.

 

[mtflat]

Since this isn't specific to 48-52's I'd suggest scrolling thru the forums and asking down in general automotive q's or ask one of the guys in the certified ford mech forum. Even in the 80-96 forum when this combination was stock will get you the help you need.
Good luck with it!

 

[5.0Flareside]

Now we have a new AOD transmission with 3rd and 4th gear burned up. It's a B&W the owner bought 6 years ago. All new. Something stuck in the valve body is what the trans. shop tells us. I guess it's back to the drawing board. When he gets some more money. Anybody have this happen to them. We are shocked this new transmission did this. This makes no sense. Maybe some of you could shed some light on this.

when i bought my flareside (in sig is build thread) had a burnt up aod also... no 3rd and 4th gear.. half the internals has burnt up. it needed a rebuild.. rebuild with upgraded parts cost me 1500 after everything. to have someone do it. and now its upgraded over stock.

if stuff is stuck in the valve body... thats the same issue mine had cause the internals came apart... it's probably time for a rebuild....


RECEIPT!

 

[Fellro]

What style ignition are you using? It is apparent that it is getting powered when it shouldn't.

 

[fasteddie]

We're using MSD ignition. An aftermarket ignition sw. It's working fine now that I have the diode on one of the "run" wires.

 

[Fellro]

Makes sense of a sort. I would be checking to be sure the feed line to the alternator is powered down when not running as well. Won't hurt anything but the battery, as it will draw down over time if not run regularly. The activation wire to the alternator is supposed to be key live only, fed from the ignition switch.

 

[fasteddie]

I have a two wheel drive 1978 F150. It has a 351/400 modified with a C6. I'm the original owner. It's been a great truck. I want to do something to it to get better milege. I don't drive it a lot but it can use up some gas. I've thought about an AOD. The trouble my friend has had with his '52 makes me think twice.