QuestionI have a 73 bug that cranks but does not start, any ideas?
Answer
Burned_bug
Very general question, very general answer: It's either fuel, spark or air(compression included).
Seriously, a quick check for spark is with a timing light or removing a plug wire at the distributor, holding it close to the connection while cranking the engine, looking for spark to jump. Be careful, you could get a shock unless you use rubber gloves.
The easy check for fuel is by taking off the air cleaner and shooting a small squirt of gas in the carb, then trying to start again. If it starts and runs for a few seconds, you've got fuel delivery/carb problem. DO NOT pour too much gas in the carb, you'll either flood the engine or get a nice explosion.
Another issue, even if you have spark, is the distributor timing may be too far off. Once again, you need a timing light to do this properly.
Finally, your engine may have mechanical problems, specifically bad compression on one or more cylinders. Obviously, you'll need a compression gauge to test each cylinder at corresponding removed spark plug.
