MG Car Repair: Webber carb, webber carb, charcoal canister

Question
QUESTION: Howard, I,m changing my Stromberg for a Webber carb. They don't have the same hook-up as far as lines go. The Webber has 2 vac line coming out the base. Where do they go? Also have a line coming out of Tappet cover. Where does that go?Thanks

ANSWER: Hi Charlie, With the engine running check for vacuum on the two ports. If one has vacuum at idle then it will go to a vacuum retard unit (if the MG has a retard unit distributor) If one has no vacuum at idle but does have on just off idle than it is called "Ported Vacuum" and would got to a vacuum advance unit on the distributor (if it is a vacuum advance type) Look at the advance unit to see if it is a vacuum advance or a vacuum retard unit.
If you are talking about the top cover you call the "tappet" cover and it is not the fuel line, then it is float bowel air vent line and must be vented. Preferably to the charcoal canister.
If you tell me what MG it is and what the ID of the Weber is, I might be able to be more specific.
Howard

---------- FOLLOW-UP ----------

QUESTION: Thanks for the reply, Howard. Sorry I wasn't more specific. I have a 77 B and the webber is a down draft carb, I think it is a DGV (no tag on it?) The tappet cover I spoke of is the side cover which covers the lifters. The front cover has a line which went to the Stromberg carb. Thereis no place on the webber for that line to hook to.  Also have the points type Dist, with a vac advance on it. I'm sure one of the lines from the webber go to that. I have a line coming from the cannister that hooked to the old carb which got rid of the fuel vapor from the tank. I'll just close that off, since I don't have the emmision system anymore. I haven't got the engine running yet since the car has been sitting for several years./ Had to put new fuel tank on and almost ready to try to crank it. Thanks again

Answer
The large hose from the side cover (tappet cover) either needs to go to an air cleaner or if there is no place to connect it there you may have to just vent it under the car (If your local pollution laws allow)
You need to check the two ports on the base of the Weber to see which is ported vacuum (vacuum that is not vacuum at idle but is there when the throttle is just opened a small amount)The ported vacuum port must be connected to the vacuum advance unit on the distributor. If the other port on the base of the carb has vacuum at idle, you need to plug it. As for the vacuum line from the fuel tank, it MUST be vented to outside air so fuel can leave the fuel tank. (If your local pollution laws will allow) (I have to say that)