OK, you rebuilt a card but have no experience with one. That leaves me with a couple of questions,
1. Have you just tried disconnecting the gas line at the carb and turned the engine over to see if in fact the pump is or is not pumping fuel?
2. Did you do the preliminary float setting properly?
3. How about the throttle plate vs idle jet setting?
4. Did you soak the carb in a carb cleaning solution to get the gunk out of where you can't see? Like the idle jets and transition slots and inside the metering plate.
Here are some things to check,
1. If all that was done, then turn to the carb. Remove the fuel bowl/s and make sure you did the float adjustment correctly. Once you are sure it was set properly to the preliminary setting, reassemble it and connect the fuel line, (for this procedure, you may eliminate the filter from the system).
2. Another adjustment is the idle jets, the throttle plates need to be adjusted so the idle jets just show below it, (when looking at the carb from the bottom).
3. Also, you need to make sure the idle mixture adjustment is set properly. If you followed the instructions, you gently ran them in to stop while counting the number of turns so that when you put the new ones in you could carefully and gently run them in to stop and then back them out the number of turns you previously counted. That will give you a rough adjustment that can be refined once the engine is up and running. If you didn't do that then the instructions should have a suggestion for how many turns to back it out so you will be in the ball park.
4. If it has a sight plug, remove it and disconnect the ignition, turn over the engine and see if the fuel bowl fills to the bottom of the hole. If no, adjust the fill valve until it just meets the bottom of the hole.
Once the adjustments are set, hookup the ignition, make sure there is no gasoline pooled on the manifold from previous messing around and Oh yes, have a fire extinguisher on hand just in case though with a cold engine the possibility of a fire is low. OH, NO SMOKING!!!! You may want to have a can or something to catch any fuel that squirts out or leaks out while doing the above adjustment.
Once you have established that you have fuel from the pump and the float is adjusted properly, ignition is good, the engine should start. If not, come back and explain how far you got.
Good luck,
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