340 not running anymore...Help Please?

On the bowls at the front and rear of the carb there should be screw in brass plugs about 1/2 way up. You remove these when the end is running to set the float level. The gas should just barely dribble out the hole. Holley now sells (and many of the new carbs have them) see though plastic plugs so you can just take a peak to tell the level.

Chances are good that they removed the spring from the secondary diaphragm on the other side of the carb. Unless the diaphragm assembly has a black two piece cover you will need to remove the assemble from the carb to get the cover off and check. Also, make sure the diaphragm it self has no tears around the edge. In one corner there is a hole that should have a check ball in it, that's another thing people remove that think they know more than Holley.

The Holley instructions you down load don't help much once you get into the carb. The instructions that come with the rebuild kits are better, but the best thing is to get a book. This is the one I have and it is very good. I got mine at Borders but Amazon has it too for less.

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