Help "Tuning" Carbie

[phil86]

Hi I have big stock 3kc and I've been told that the Carbie needs a "tune" which is why it is idling a bit rough and some times stalls when idling or taking off when cold. How do I tune the Carbie? Could this really be the reason?

[158kw4k]

Take it into a mechanic if you haven't tuned a carburetor before. Would cost bugger all and at least you no it's been done properly.

[altezzaclub]

Could be timing/points/plugs related, so do those first.

 

Check the points visually to see they are still reasonably flat on the contact faces. As the get old a hollow burns into one side and a matching volcano builds up on the other.

 

Check the gap with a dwell meter, as feeler gauges are only good for new flat points, because of the volcano.

 

Set the timing to 10 or 12deg BTDC

 

Check the plugs for gap and how burnt the electrodes are. Are they black and sooty from running rich?

 

Set the tappets while the plugs are out.

 

Then worry about the carb. Mixture screw when warm for maximum idle and set the idle speed with the throttle stop screw. Check the operation of the choke, make sure it goes full on and full off like it should.

 

Good luck-

 

 

[ae824ate]

Like altezzaclub said, the only adjustment you have on the carby is the idle mixture jet, and the idle speed screw. Id be looking at the other things altezzaclub suggested. Carby rebuild kits arent too expensive, if you feel the need to clean out your carby for piece of mind.

[phil86]

Thanks for the help, have already replaced plugs and points. I guess what I was really asking was how to adjust the mixture screw and throttle stop screw probably a stupid question but have never really worked cars before