starting problem???

Please help! I have an 87 Chrysler 5th ave. In October I put a new engine into the car; a rebuild carb. When I go to start the car, it turns over and almost starts. Eventually does start on 3rd try. (Of course when I took it to the mechanics, it started fine everytime).

I think it is fuel related, but I keep my tank over half full all the time; The mechanic did say my fuel pump is fine (and he showed me the fuel being squirted into the carb.) The fuel filter was changed by the guys who did my engine. I have had the battery checked; it is fine.

Help! I am taking it to seeburg in the morning to see if the catalytic converter is clogged. Would that affect starting? Thanks in advance.

the only thing that will effect starting is spark, fuel, and compression.
since it's a new engine, it probably isn't compression.
becasue it is carbureted, you might want to check the level of your float bowls, and possibly the choke.
the next step, after you figure out that it is gettting enough fuel, is to check the spark.