O.K. This is not about my Vespa but you guys are the friendliest. I have a 50cc SYM that the dealer didn't know what to do with so the distributor stepped in and sent me a new carb so that I would not have "check out the whole problem" delay. I installed the new carb with the new recommended mainjet and I can not get her started. I am assuming that it is something simple. The distributor is now closed for the day and I am excited to get her going. Any thoughts?[/b]
Could be any number of things. A new carb is not "plug and play".
Did you verify that the idle mixture screw was set at the recommended number of turns for the initial setting?
Did you verify that the float height is correct?
Did you make sure to seat the auto-choke properly and reconnect it to the power source?
Did you verify that fuel is flowing to the carb when you apply vacuum to the fuel tap vacuum line?
Do you have spark? (while the plug is out, you may want to look at it to see if it is wet... if dry after a lot of starting attempts, you probably are not getting gas flow)
Have you flooded it from too many unsuccessive starting attempts?
You might want to try starting it with starting fluid (ether) initially.
I've done a few of the items mentioned. I did not check the plug to see if it is wet. This will be my next step. It doesn't smell like it is flooded at all. If it is dry, I will try to acquire some ether.
So, there wasn't any gas getting to the carb. The carb function is dependent on vacuum and there was air trapped in the float bowl. I first loosened the air intake clamps so that I could twist the carb and access the bottom. There is a drain screw at the bottom side of the bowl. I loosened the screw, then opened up the throttle for a few seconds with the electric start going, then let go of the throttle and it started. I then tightened the drain screw and clamps with the engine going. It continues to start with no effort. Yeah! Thanks for the help and thanks to the guys at Cater Bros. for their guidance!
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