Before you fire off any suggestions please note that my knowledge of cars is very limited, though I am very eager to learn how to make my car purr.... I've just had the car serviced (new distributor, point, and fuel pump) as a result the car ran great for about a week. I go to use it the other day and the car will not stay running. As soon as I shift into gear it putters and shuts off. messing around tonight I found that if the line on the left in the picture below (to vacuum source) is disconnected from the air breather the car will idle smooth and there is no issue shifting into gear. I know it activates the duct in the neck of the air cleaner but it appears that it does not matter if the duct is open or closed only if that line is connected to the breather. If the line is allowed to blow air freely the car runs much better. Do I need this vacuum line connected to anything? What can I do to solve my idle issue?
Ok...Your engine.(Any internal combustion engine) Is just a big heavy air pump. It just needs fuel/spark and combustion to keep it pumping air (sort of like a perpetual motion machine...Sort of) Your engine quitting on you, as you describe is due to lack of airflow through the carb or ecsessive fuel entering the engine. You pulled a vacuum line creating a vacuum leak and the car ran better...You gave it much needed air to mix with the fuel it was pulling in through the carburetor. Possible cause: You have a stuck choke plate...It isnt opening enough to give the engine the air it needs causing it to stall due to recieving excessive fuel for the air it is pulling in. OR: The engine is receiving too much fuel due to a stuck float/needle and seat, allowing too much fuel through the carb into the engine. Or the curb idle is suddenly too low( its possible for the idle screw to back off due to engine vibration) Or the fast idle isnt high enough for the engine to run while cold/warming up. Or, again...The choke isnt working properly. Stuck closed or open. The engine apparently ran fine then suddenly went off kilter. So, something changed or something failed. Couple questions for you... Is this engine a 6 cyl or a V-8? Was a new fuel filter installed when the pump was changed? When started cold...Does the engine idle high and then come down after you step on the gas and release it after a short warm up period? Does the carburetor look dirty if you look down into it with a light (do this with the engine off) Do you notice a heavy gas smell when the car is running? Do you notice a heavy gas smell when the car dies as you have described? Have you noticed if you have black smoke coming out the tail pipe when the car is running? Did you notice such as stated above when the car was running well before it acted up on you? If you can answer these questions accurately we can probably nail down your problem for you...
Answer to #1: The vaccum line is not "absolutely" necessary as long as your carb is getting good air flow from snout or heat exchanger. #2: Areas for a quick look and hopefully quick fix: You might check all your vacuum lines or vacuum "caps" to (or on) the new distributor and make sure one hasn't come loose. I've also found these old cars need to be started properly and warm up good before they'll run smoothly. After you've done that get some carb cleaner and use it to clean the air cleaner duct valve (in the snout), the temperature sensor (shown in your pic) and the carb itself. Didn't happen to "wash" the engine bay did you? If so, water can wreak havoc on the ignition system and cause symptoms like you've described. If water is suspected, remove distributor cap and let it dry completely. Use compressed air if available to speed things up. Make sure all spark plug caps are on good and tight.
You forgot to mention the fuel/spark also needs oxygen to burn ... Maybe I not thinking clearly this morning but what does a 6 cyl or V8 have to do with why he is having this problem? Isn't an engine is an engine?
Seeing is how you are in Canada,you really should have the vacuum line connected. This system draws hot air from the exhaust manifold and keeps your carb from "icing" up. You only really need it when the outside temps go below 40°f,or so. As was said before,check your choke setting and make sure it opens fully when the engine is warmed up. If your problem started with a cool down where you live,the choke would be a good suspect.
Manual chokes still need you to give the throttle a nudge to set up the high idle right? Did Mavericks come with a manual choke? or was this added by the previous owner? I don't know. clint
I had hoped that the statement "big air pump" made "oxygen necessary for combustion" a given. Correct 6cyl or V-8 does not matter...Type of carb does. We all know how kwirky the 1V on the sixes can be. I should have asked what kind of carb. :Handshake
A manual choke requires you to push the throttle to the floor before engageing the choke. It also requires you to push the the choke off once the car has warmed enough to run on its own...You may be correct and it may be operator error or it may be debris in carb that flushed itself loose and now all is right with the world. Cold air requires alot more fuel on start up in order the get adequate fuel vapor to fire off the engine. Hence the need for the choke. I would leave the carb heat set up in working order if you intend to drive the car in cold weather. Its function as stated is to prevent carburetor iceing by warming the incoming air. Dont leave vacuum lines open allowing a vacuum leak. Its not good for the engines valves or fuel economy/consumption. Good luck!!!
