i changed my engine because of my old A12 is literally drinking mineral oil! about 3 litre in 5 days!

my mechanic advice to do conversion as it'll costs the same, but with a better engine (A15)

as you know what B310 in malaysia comes with manual choke carb. but in my car, my choke assembly have been removed (by me) as we don't really need it here.

the rough idle is due to carb icing in cold mornings. you can test this by touching the carb after just 1 minute of starting the engine. the carb will be freezing cold due to petrol evaporation. but as the engine warms up, so does the underhood temp. this will keep the carb cozy and prevent icing.

I've been using my A15 for 5 years. and i learned a lot of tuning from this site. you can do a read up from the tech section on the maintenance of the engine, distributor and carb. all the specs are given also.

ps. when you re-gap or clean the contact point, make sure your feeler is clean, and wife the contact point with paper towel after sand paper and adjusting the gap with feeler to remove any oil residue