Need help! Carburetor question

[Jaytee]

Need help. My 73 datsun 620, has a fresh rebuilt Hitachi carb, we can get it too start, and run using gas directly into the top of carb, it will idle, Rev up using accelerator from inside, everything is fine! But.. ... when we turn it off, and try to restart without direct gas into the top of carb, it will just turnover! Add a little fuel into the top, starts right up. Accelerator pump is new, gaskets, everything, complete rebuild. Any help ????

[datzenmike]

Is this with the engine warmed up?

 

Does the choke work? It should be closed on a cold engine. This is needed to richen the mixture needed to start a cold one.

[LenRobertson]

Jaytee - Do you think this is the original size engine and carb for your 620? Was this carb working okay before the rebuild or is this a different carb that was rebuilt?

 

Len

[datzenmike]

Look in the top of the carb and pump the gas several times. What you should see is a squirt of fuel from the accelerator pump. This would do the same job as pouring gas in by hand. Pump twice and try starting it.

[Stoffregen Motorsports]

Try tipping in to the throttle when you crank. If it fires as you're slowly cracking the throttle, then you simply have some tuning issues.