68 Coronet 500 Issues

[uecker22]

Recently bought stock 68 Coronet 500 that had been in storage for 15 years. We did basic maintenance and got the car road worthy and drove around for several weeks. The car suddenly stopped running during a Sunday stroll we can't keep the engine running.

We thought initially it was a fuel issue and replaced the fuel pump, fuel filter, installed new gas tank, sending unit, cleaned the gas lines, carb rebuild kit, new distributor cap, plug wires, spark plugs. The car should now be getting clean fuel but won't start and will barely sputter even with coaxing of throttle.

Any ideas or pointers on what to try next? Our mechanical knowledge is somewhat limited but will keep plugging away. Any assistance is greatly appreciated.

 

[Bigal75]

Is the ignition firing?

 

[uecker22]

I'm embarrassed to admit but I am unsure. Is there an easy way to determine if ignition is functioning? Thanks.

 

[Propwash]

real easy way is to pull a spark plug, reconnect the spark plug to the spark plug wire, have someone crank over the car and look for a spark crossing the gap in the plug

 

[khryslerkid]

real easy way is to pull a spark plug, reconnect the spark plug to the spark plug wire, have someone crank over the car and look for a spark crossing the gap in the plug

And make sure the body of the plug is grounded.

 

[uecker22]

The engine will briefly fire & sputter for several seconds about 1/4 of the time when attempting to start while pumping throttle. Would this indicate the coil is functioning? Can coils become weak in which spark is still being sent to plugs but not enable engine to function properly?

 

[khryslerkid]

Sounds like a fuel issue if you're pumping on the gas to keep it running. You could try useing a oil can or squirt bottle with gas in it. While it's cranking squirt a small amount down the carb while cranking. Do this outside and be smart about it in case if a back fire! It will tell you if you're not getting enough fuel to keep it running.
Make sure you don't have a vacuum hose off. A vacuum leak will make it hard to start too.

Good luck.

 

[SlinktRR]

Assuming you have a ballast resistor and electronic ignition, take a multimeter and check voltage at the battery side of the resistor with key on, should be battery voltage. Then check at the coil side or at coil positive, should be less than that, say 10v. If you turn the key to "start" like you are cranking, the meter should show battery voltage. If it goes to zero, you may have a problem with the ignition switch, wiring, or the infamous orange box.