My 315 poly keeps running after everything turned off..

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twodog45

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My 1958 dodge d100 315 poly keeps running after I turn key off( brand new ignition), and disconnecting battery! Luckily I run a electric fuel pump so I'd finally dies when it runs out of fuel.
Any suggestions??
 
It can only keep running if it’s still getting power to the ignition circuit. Disconnecting the battery doesn’t stop the alternator from putting out power.

Put a meter on the circuit and see where it’s still getting power from after the key is turned off. It could be a failed ignition switch (key) or perhaps it it connected to an “always on” circuit that keeps the ignition circuit energized.

If the ignition circuit is always hot, all you need to do is crank the engine and it will start and run until either the ignition circuit is interrupted or you remove the fuel.
 
They used to have an electric solenoid to set the idle with while the engine is running.

Turn the key off and the solenoid retracts, then it closes off the fuel/air of the idle curcuit and the engine stops.

________

Note: If your idle is set at 900 rpm it is set too high. The engine will want to run on when you turn off the key.
 
Put the electric fan ( or WHATEVER ELSE is on the ignition circuit) on a separate circuit using a relay.
 
What modifications have you made? Electric component additions? cooling fans? Changes to charging system?

I don't know how the coil resistor bypass works on those, MAY come from the starter solenoid. Check that maybe the contacts are sticking.
 
Sticking starter sol would keep starter engaged...
My bet is something to do with how you wired up the elec fuel pump &/OR the new ign switch is wired up wrongly or is faulty.
 
It is possible that it could be dieseling. Basically if there is a bunch of carbon buildup it can glow red and act as an ignition source even when the key is off.
When I was a kid we had a 73 Maverick that would run for a full minute after the key was turned off.
 
I have redone all ground cables. Carb rebuilt by professionals. Pertronix electronic ignition in distributor, wired correctly. No more resistor on top of coil, need 12 volts for electronic ignition. New solenoid on fender for starter. New ignition on dash. New electronic fuel pump wired to acc on ignition. Fuel regulator before carb. I did see some light or spark coming from generator while running. All wiring done according to wiring diagram in shop manual. The idle on carb (stromberg ww) is done with adjusting screw.
Manual choke also.
 
Disconnect the wires on the generator and run it on the battery. Try it again.

The ignition will shut off when you turn off the key.
 
I was thinking; that the 58 has an old-style mechanical regulator with point-type switches. I forget how exactly they work, but it sounds to me like yours is sticking in the run position, or is not being properly controlled by the ignition switch, or is just wired wrong.
If you have a working ammeter, it should indicate which way the power is flowing, and it should show straight up when you shut the key off, indicating no current flow.
I think.....
 
Run a kill switch to the coil wire...untill you figure it out. The kill switches were used as theft deterrents in the 70s.
 
It is possible that it could be dieseling. Basically if there is a bunch of carbon buildup it can glow red and act as an ignition source even when the key is off.
When I was a kid we had a 73 Maverick that would run for a full minute after the key was turned off.
It will make a diesel sound though if that's the case kind of like a horse snorting LOL!
 
Where are these regulator point type switches?
When the electronic ignition was installed, the only thing left in distributor was the mechanical advance.
 
if it is indeed still running on the ignition something is l keeping the hot side of the coil juiced up.
 
I have redone all ground cables. Carb rebuilt by professionals. Pertronix electronic ignition in distributor, wired correctly. No more resistor on top of coil, need 12 volts for electronic ignition. New solenoid on fender for starter. New ignition on dash. New electronic fuel pump wired to acc on ignition. Fuel regulator before carb. I did see some light or spark coming from generator while running. All wiring done according to wiring diagram in shop manual. The idle on carb (stromberg ww) is done with adjusting screw.
Manual choke also.
"New electronic fuel pump wired to acc on ignition." THERE is your problem. You need to isolate the fuel pump power from the ignition.
 
Thats not causing it to keep running. When key is turned off it kills power to fuel pump, it's an electronic issue
 
Thats not causing it to keep running. When key is turned off it kills power to fuel pump, it's an electronic issue
I'm not talking about the fuel pump keeping the fuel going. What I'm talking about IS an electronic issue. The fuel pump is feeding power into the ignition once the key is cut off. An electric fan, or most any other electric motor will do the same, unless you isolate the power source from the ignition.
 
Where are these regulator point type switches?
When the electronic ignition was installed, the only thing left in distributor was the mechanical advance.
In the voltage regulator.
 
I'm not talking about the fuel pump keeping the fuel going. What I'm talking about IS an electronic issue. The fuel pump is feeding power into the ignition once the key is cut off. An electric fan, or most any other electric motor will do the same, unless you isolate the power source from the ignition.
I'll look into that too then
 
A mechanical regulator has contacts in them that look just like breaker points for ignition. I suppose if those are stuck closed it may keep feeding the ignition. Pop the cover off and take a look.
 
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