For backfiring, it could be due to the rich condition, ignition timing too advanced, a poor cylinder, spark plug and/or related components. That would require tests to confirm.
June, 12, 2012 AT 4:15 AM
Spark plugs are new.
What does ignition timing mean?
After letting the choke butterfly open. The backfiring reduced. But is still there.
Here are the pictures
June, 12, 2012 AT 4:22 AM
Sorry there's nothing much to see.
It was night time when I took these
June, 12, 2012 AT 6:17 PM
Ignition timing means the time the spark plugs fires. It is adjusted by turning the distributor clockwise or counterclockwise and you use a timing light to check. If contact breaker points are used, the gap clearance would affect the timing. The wider the gap, the more advanced it is.
I don't see any choke plate in the pictures.
The rubber capped plunger at bottom of last picture is the accelerating pmp. Ensure you have a fine spray into the carb at top inner part of carb barrel. If there are none or is too little, you would have hesitation and possibly backfiring as well.
June, 14, 2012 AT 1:53 AM
When I press the pump it sprays fine. But the secondary doesn't spray any.
Sorry its the picture, you cant see the plate because it's too dark. Notice the second barrel is dark while the first one, you can see the butterfly(gold). The secondary is closed.
Should both of them spray gas at the same time? Or is it supposed to spray on the secondary only when the second barrel opens?
Ill take new pictures. Those you can see : D
June, 14, 2012 AT 1:37 PM
The secondary does not have any accelerating pump functions. Only the primary has it.
I can't seem to be able to see the pictures now as they are not loading correctly. Maybe I will try again later.
June, 14, 2012 AT 2:13 PM
Ohh... i thought it's supposed to be pumping as well :D
haha. sorry about that. new knowledge for me.
i forgot to take pictures earlier this day. haven't been able to go to my grandparents house. that's where the car is.
thanks for taking the time to help me with this problem.
why does it have an exit when there's no pump action for that barrel?
June, 14, 2012 AT 5:40 PM
The accelerating spray is from the side of the barrel. The central venturi for the primary and secondary are for fuel to flow when suction is created by air flowing through it. They do not spray.
I was expecting a big butterfly covering the barrel. Seems it is only for the primary venturi.
June, 15, 2012 AT 2:05 PM
I took a video of my carburetor.
I'm gonna upload it later.
I let the choke stay open. I tested and it still backfires every once in a while. The secondary butterfly opens well at 70-80% throttle but I'm still having the backfiring problem.
Also, the engine power is very low. I'm having a hard time with this.