PM replied.

Pm sent to datsun repair squad

Might be worth having a look at the vacuum advance for leaks. You might be able to use a syringe, (or just suck on it), to check the vacuum advance is working on the distributor with the cap and rotor off.

Going to the work shop tomorow have give it another go

I would ask my mechanic about it.

But you can look through the site glass to see if the fuel level is exactly centered. If not, start with that.

It is unlikely to be the fuel pump, because a bad pump would have worse symptoms as it runs faster. But you can do the two simple Fuel Pump Tests.

Yep that.s right same thing happing agine with new carbie

So to be clear... the same symptoms occured with the previous carburetor and with this new carburetor? If so, it suggests (but does not prove) that the problem is not with the carburetor.

Me and my mechanic

who tuned it? take it back to them?

Recently I have fitted a new carby - cheap factory brand. The car has had a flat spot for some time and I was hoping the new carby would solve the problem. The last time I tuned it by adjusting the float level and idle screw. Car runs well in fourth a bit after 60. Car is not running well in these situations - starting off at traffic lights and will almost stall and starve unless I rev it up a bit first before letting the clutch out. Other times changing from second to third and getting back on accelerator in fourth under 60 and also mainly left cornering. Maybe it is the fuel pump?