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Message: <blockquote data-quote="71ProjectJunk" data-source="post: 402390" data-attributes="member: 7655">There is something wrong with either the carb or the electrical system/distributor, and I would bet that if it sometimes runs great that the distributor or the electrical system is the issue. Usually a carburetor issue is always there. Check the grounds to the engine, make sure that you have good ground, you could make a supplemental engine ground just to make sure. Check the coil, it could be going bad. Check the wire going from the points to the negative side of the coil, make sure that it is not grounding itself or that there is an internal short on it. When you have issues with the engine not starting check the + side of the coil and see what voltage you have there,  with points there is a resistance somewhere and you should have about 9V, if it is less than 9V or more you have an issue. Check the advance plate on the distributor, make sure that it is moving smoothly and that it is not getting stuck. As for the carb, a lot of carburetor issues can be diagnosed with the air cleaner off and the engine running. You could have a float that occasionally sticks, when it does the fuel just drips down the carb boosters and just floods the engine. A piece of debris may be stuck on the needle and seat on the carb, usually happens when you work with rubber lines, and a small piece of the rubber line just breaks off of shears off and gets itself stuck on the needle and seat. When the engine is not running well, take the air cleaner off and look down the carburetor. See if you can see fuel dripping out of the boosters, you should see no fuel dripping into the engine at idle, all the fuel is coming in under the throttle blades through the idle circuit and you cannot see it. A piece of debris, usually rubber hose, can go into the carb and float around inside the bowl and give you headaches. It can go onto a main jet and block it or partially block it. when I have seen this the car usually idles well, but when you get off the idle circuit, it runs horribly as one side of the carb is running way lean. If you have a blocked jet you will see it when you accelerate the car in neutral and look down the carb, one of the booster will be flowing a lot more fuel than the other, it will be quite noticeable.  Please be careful when looking down the carb with the engine running, especially an engine that is not running well. It can backfire and burn off you eyelashes, ask me how I know...The only other thing that I can think off would be the timing chain. Stock timing chains have nylon teeth and they wear out. I have never had this issue personally, but I do know that they can wreak havock when they are about to let loose and the chain is all stretched out.</blockquote>

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