I replaced the standard Datto carb on my A15 Nissan engine with a 32/36 Weber.
I got the carby reconditioned and re jetted to suit.
The guy said the shafts where a little worn but should be OK.

I spent many hours making a adaptor plate to fit.

When it all went together, it goes like a rocket, but, the engine hesitates when moving off from slow or stopped.
I thought it may have been my Home made adaptor, so I lashed out for a shop bought one, no different.

Took it to a mechanic to have a look, he charged me $160.00 and did nothing and said the shafts were stuffed. I can take it to another carby place to have the shafts drilled and rebushed, but then they want to tune it on the car, so I'm looking at about $85 for the reshafting and possibly up to another $150 for the dyno tune, but I don't want to spend all that money on a carby that is stuffed any way. I was also told I should buy a new Webber at about $500, but then told the new ones are made in Spain and are Crap anyway, the metal carrodes quickly!

I forgot to mention, it runs on a bit after ignition off (possibly timing), takes a bit to settle back to idle, and the fuel economy is BAD about 20mpg for a 1500cc.

So Gents I am perplexed, does anybody have any ideas?

Oli

I faced this problem twice...i solved it by doing this:-

1.) Adjust distributor timing ( advance / retard )

2.) Adjust tappet adjustment slightly..

It worked for me. Perhaps you are facing some other problem. Sorry if these tips didnt help.