My timing light didn't work on my Eagle either. Later it worked on my friend's truck. Turns out the battery was too weak and the spark on #1 cyl was weak, too. Anyway, replacing my battery and adjusting the timing fixed my starting problem (I had a similar sound as you). I'd have an auto store test your battery. If that's not it, inspect your distributer cap/rotor and check your spark plugs. If you still have trouble and you can get it out, have the starter tested. I installed HEI and for around $100 it was a worthwhile upgrade. I never really mess with the carb, except the idle, so I can't help there.