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Discussion Starter #1
Got the `66 running again - has a hesitation on acceleration.Idles fine,revs fine in the driveway,but under load wants to hesitate.The car has a 289 with a Holley 4 barrel w/manual choke.If I close the choke while running the car seems to run fine.(If you take the air cleaner off and look at the choke the position where it runs best is about 3/4 choked.Thinking I may have something clogged.Any Ideas?Thanks,Lee Fuel filter is clean.
 
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Checked both float levels they are fine.Haven`t really driven the car since I bought it in `99.Just recently rebuilt the carb.
 

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Assuming the float is set correct, I would look at the filter (possibly clogged), fuel linefor obstructions and the possibility (very strong) of a pin hole that developed in the fuel pump diaphram while the car was sitting, under load, this will cause a fuel starvation problem.
 

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Have you checked for vacuum leaks? Are the throttles closing all the way, front and rear?Recheck the floats and air idle mixture screws. Make sure that your timing is on, I know that sounds crazy. If it were air bleeds I'd think the car would run rich. It may be more than one problem.Make sure that the accelerator pump has no slop and doesn't bottom out. Don't get caught up on putting the lightest secondary spring in as I was told once. Somewhere around the middle of the pack seems to work good.Did you make sure that the new gaskets were the same as what you took out?
 
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Did you check the levels while it was running? If the car doesn't need the choke with the breather off but still stumbles, check the accelerator pump. Is the arm loose? Does it operate freely? Does the discharge nozzles squirt? If it runs ok & idles ok but stumbles on acceleration, it going to be in the accelerator pump system. Also is the idle stop screwed in a lot? Enough to uncover the small transition slots? This will make it run horribly as well. It causes the carb to go into the main circuit instead of using the idle circuit. Try the pump system first. Note... you might need a bigger squirter, you didn't say what carb # or what has been done to the engine. PM me if you need more info...
 
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