I drove (it was running fine) my car into storage, and it was in storage for a year. I just got it back and can't get it started. When I try, I get a backfire out the carb with an actual flame, and no start. Engine is a Mopar 383 running off a GM 4-pin ignition module. Dizzy is a "Firecore" magnetic pickup type (uses Mopar reluctor & pickup). Plugs, wires and dizzy, & cap are all nearly new and are the ones I drove in on. There is fuel and battery is charged. About 6 months ago I went to the storage to start the engine. It wouldn't start and I determined that the module was bad. I replaced it and started the car, and ran it for a few minutes. That was the last time I ran it. What I've done so far: Put timing to TDC by the "Finger on the sparkplug hole" method. Checked all wiring to the module & dizzy. Swapped the module for a new one. Verified that all plugs wires are where they are supposed to be and firing order is right. Did a compression test: All cylinders are between 165-180. I'm looking for suggestions what to try next. Just to give you something to look at, here's the victim:
When parked what fuel was in it? This new fuel is crap and if you didn't store it with stable or some kinda additive it's probably bad. Just a idea.
Ignition switch is working properly? The pickup coil air gap is correct? Did you try fresh gas? he's not joking about it going bad....
Ign switch is fine, and overall the car acts like it wants to start. I'll check the gap tomorrow- that's a good idea. Can old gas really cause a symptom like my backfire fireball? I did put some Sta Bil in it when I put it away, and I never thought of this symptom going with old gas, but I'll drain it or run it off a gas can tomorrow to test.
Sounds like a lot of things have changed since you drove it. I would back track and see what changed.
Sounds like carb problems from sitting, or gas gone bad, - dried up internals, blown power valve, etc I would drain all the gas and replace with new.
"out the ass it's in the gas, out the carb it's electrical......Backfire ,that is. was told that 40 years ago and it has saved me a lot of time.
If it ran 6 months ago and now it pops out of the intake, sounds like the spark isn't getting there at the right time. What could change that? Look for moisture inside the cap. Think about things that have changed. Also look for arcing marks in the cap and on the rotor.
Timing chain jumped.? I had a 383 magnum in a 54 Ford PU, timing chain jumped while tryin to start, bent 16 out of 18 push rods. Went to pick an pull in So Cal, stuck 16 push rods in my socks, and walked out.
when you changed the module is there any chance you flip flopped the two wires that go from the dist. to the module?
Lifters have bled off and throwing valve timing out. I can't guess the Lotto numbers either so everything's a lottery.
I always like it when people post with the solution to their problem, so here's mine: It turned out the magnetic pickup in the dizzy was moving a little because the connection between it and the plate it sits on (similar to a breaker plate) was a bit floppy. As a result the gap, which is supposed to be .008, was all over the place to the point where spark was arriving at the wrong time or not at all. We got things tightened back down and it seems to be running fine. Thanks to all for the suggestions. I tried many of them before figuring it out. Props to Squirrel for having the best guess...
Something else you could check that happened to me one time, The distributor drive gear slipped on it's shaft because the oil pump did not want to turn. Maybe caked up oil after setting for a long time. But the gear slipped and changed the timing. If they slip once they will do it again. It is not uncommon to pin the gear to the shaft on race motors to keep them from slipping. If you have that problem , you can fix the timing and it will unfix itself at random. Just a thought. Dan
One reason for the oil pump to lock up is the relief valve sticking. Pressure can go high enough to blow the oil filter off of it's base. Seen that happen . Usually happens on a cold start when the oil is thick.