Answer: Although there are many possibilities that can cause this condition, based on the information that you’ve given me, I would look at two possibilities.
The first is fuel related and is called vapor lock. This occurs when fuel in the fuel lines or carburetor begins to boil and goes from a liquid to a gas. This gas, which is now under high pressure, blocks the flow of fuel, resulting in the symptoms you're describing. The 427 engine produces a lot of heat, so this is a real possibility. To determine if this is the problem you can try putting insulation on the fuel lines that are directly above the engine, or you can try spraying cold water on the fuel lines the next time it happens. If either one of these helps, you know what your problem is. Remedies include permanently affixing insulation to the fuel line, rerouting of the fuel lines away from heat sources, and metal plates that go in between the engine and the fuel line. These plates usually bolt underneath the carburetor.
The second thought that comes to mind, and is often overlooked, is a failing ignition coil which will produce these symptoms as it gets hot. If this is the case, the only solution is replacement of the ignition coil.
Question: How do I get a 1954 Dodge Coronet to run after sitting in a garage for more than 30 years? It has a 6-cylinder engine and a power flight transmission with only 31,000 original miles.
Answer: You don’t. You make either a lamp or a planter out of it because this column is too short to address all of the potential problems you might encounter. If you still insist on getting it running I’ll give you the basics since I’m asked this question all the time. This information would apply to any engine that’s been sitting for more than five years.
I’ll have to make the assumption that it was running well when it was parked 30 years ago. If you’re not sure about this, then make room for a large lamp or planter.
First, make sure the engine is not "frozen." Remove the spark plugs and put a few teaspoons of Marvel Mystery Oil® in each cylinder. Leave the spark plugs out and try to rotate the crankshaft with a socket and breaker bar on the large bolt in the center of the crankshaft pulley. Make sure to rotate it clockwise (as you’re facing the front of the engine) or you might loosen the bolt. If it moves, the engine is not frozen and it stands a fair chance of running.
Now you're going to have to get the fuel system, ignition system and lubrication system in working order.You'll need to clean or replace the gas tank, flush the fuel lines, replace the fuel filter and rebuild the carburetor. The ignition system may be OK but I would do a routine tune-up including points, spark plugs, condenser, rotor, ignition wires and distributor cap. You’ll need a new battery as well.
The lubrication system is very important. I always try to get oil circulating through the engine before I try to start it. The easiest way to do this is to disconnect the wire that goes from the center of the distributor cap to the coil, thus preventing the engine from starting. Crank the engine until you can see oil in the upper half of the engine (usually through the oil fill cap, or remove the valve cover).
Reconnect the wire from the coil to the distributor, and try to start the engine. As long as it has fuel and a spark it should run. Often, this is all it takes, but after 30 years, there are many things that could complicate matters. If you’re lucky, and you get the engine started, make sure that the rest of the car is safe to drive. Especially the brakes.
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