Thread: 350 Ignition Problems

Tweet

Hey guys,

I have a 350 with an edelbrock 1406 carb on it. The motor will not start unless I turn the key all the way forward then let go of it, If I hold the key in the start position it will just keep on cranking. I've changed the plugs, wires, distributor cap, and ignition switch and nothing seems to help at all. Any ideas? I'm going crazy and could really use some help. Thanks.

Sounds like you don't have any power to the ignition system when the key is in the start position.

What do you think I should do?

If your ignition switch doesn't send 12V to the distributor or coil when it is in the start position, you have to add a wire from the starter solenoid to the + terminal on the coil or distributor. It will connect to the "R" terminal on a GM starter or the "i" terminal if you are using a Ford solenoid.

Whats the history of the car? Has it ever started right? Is it a new build? Did this just start happening?

if it all worked before you could have a bad switch or switch may be out of adjustment if mounted on the column. power out put can be verified by ohm gauge or test lite .ign #1 should ways feed 12 volts off switch when cranking

Originally Posted by sfort

Whats the history of the car? Has it ever started right? Is it a new build? Did this just start happening?

Originally Posted by pat mccarthy

if it all worked before you could have a bad switch or switch may be out of adjustment if mounted on the column. power out put can be verified by ohm gauge or test lite .ign #1 should ways feed 12 volts off switch when cranking

I agree, I wouldn't "hot wire" the car with another switched ignition wire to the coil. While it will work, it's a band aid repair. After you address the history question I'd bet that Pat's on the right track with a faulty ignition switch failing to make contact to the "ignition during crank" contact. Have someone crank the engine while you put a test light or volt meter on the + coil post. With a clip on test light you can even do it alone

could be resistor wire off?

Originally Posted by cffisher

could be resistor wire off?

Pretty sure the resistor wire only came into play in the "Run" position, dropping the voltage to the ignition once the engine was started. The coil gets the full battery voltage in "Start", as I recall? I'd have to go back to a schematic to be sure....

I'm not talking about hot wiring....it is common for a lot of vehicles to lose power from the ignition swith to the coil in the start position. The in turn have a wire from the starter solenoid to the ignition coil from the factory. It bypasses the resistor, or resistor wire, and sends full 12V to the ignition system when the key is in the start position. Here's a diagram...I'm talking about the wire from the "I" terminal on the starter to the + on the coil. If your vehicle wasn't originally equipped with this wire, then there's likely a problem with the switch. If your car is something you put together, then add this wire and your problem will be solved.

Originally Posted by 35chevy

I'm not talking about hot wiring....it is common for a lot of vehicles to lose power from the ignition swith to the coil in the start position. The in turn have a wire from the starter solenoid to the ignition coil from the factory. It bypasses the resistor, or resistor wire, and sends full 12V to the ignition system when the key is in the start position. Here's a diagram...I'm talking about the wire from the "I" terminal on the starter to the + on the coil. If your vehicle wasn't originally equipped with this wire, then there's likely a problem with the switch. If your car is something you put together, then add this wire and your problem will be solved.

OK, I understand what you mean, but to me the key is still "Did it work right, and has just started giving you this problem?, or "Is this a new installation, giving you this problem on initial start?" I think we need the answer to that to help get to a solution.

This discussion has made me think back on this system. The resistor wire, or ignition resistor was there to keep from burning up points once the engine was running, right? At what point in time (or design) did the resistor wire disappear? Another question here might be the type of ignition system? Just pondering.

in 71 gm started to use HEI distributors at that time the resistor wire was eliminated

There are also coils available that have the resistor built in, eliminating the need for the external resistor or a resistor wire. I installed one on an old Dodge last week and removed the external resistor.....It's much simpler and less cluttered doing it that way. I agree with you Roger, the OP's problem cannot be resolved without more information.

Oh, and one more thing...Let's say you put together a points system on a hot rod and you have voltage going to the coil at all times from the ignition, I'm saying in the run and the start position. The vehicle will both run and start off of approximately 6v. Adding the wire from the solenoid to the coil will increase voltage to a full 12v at the coil in the start position, in turn producing a hotter spark at startup. I can see where this would be of benefit and could reduce cranking time. Just throwing that out there for those who may have that type of setup.

Its a 350 crate motor with 36,000 miles on it. No ignition problems what so ever until recently it just happened out of the blue. Thank you all so much for helping right now I really appreciate it.