QUOTE(gemini sharti @ Oct 23 2013, 04:10 AM)
Yes, there was symptom of engine lacking power but after the carburetor has been serviced, the car runs well. There is no problem when I drive the car, the only thing is sometimes it won't start.
The problem of "engine can crank, but does not fire" has many causes mainly classified under fuel problem, electrical problem and compression problem, and need to check to eliminate each one.
1) Take out the spark plugs and look at the condition for clues. You can google "spark plug condition" under images and you can see lots of pictures & guides.
2) See if your carburettor auto-choke is at the right position for cold engine.
3) To see you have a 'flooded engine', press fully the petrol pedal & maintain at that position (do not pump) and crank the engine. This will help clear excess fuel in flooded engine.
4) To see if you have 'no fuel supply' problem, open the air filter, push back the carburettor piston and spray some carb cleaner down inside (to be used as fuel), then crank the engine. If it fires for a short while, it's confirmed.
5) Electrical :
To test whether ignition system is the problem, remove one of the cables to the plug, fit in a spare spark plug, place this on the engine body with the plug screw thread touching the engine body (use a tape to hold in place), then ask a helper to crank the engine. Observe whether got spark. Caution: high voltage, do not touch the set-up when cranking - can give you electric shock. Also, if there is petrol leaks nearby, it may ignited by this.
You can google "testing ignition coil on plug" e.g.
http://autorepair.about.com/od/troubleshoo...st-manual_2.htmhttp://www.doityourself.com/stry/how-to-te...-in-a-vehicle#bhttp://www.youtube.com/watch?v=mUOmsGiirTUThis post has been edited by Albert B: Oct 23 2013, 05:20 PM