Rough cold starting

[Mmoony]

Hi guys, got a 1984 4x4 as a daily driver. It’s been rough getting it started first thing in the morning, runs okay the rest of the day. Here’s what it will usually do on an cold start: engine fires, then dies. Fires again, rev it up, dies. Repeat several times. Gets going enough to get in gear, makes it several feet, dies. Makes it down the road I live on, go to pull out on the main road, dies. Get going up to 55mph, shift into neutral, might die. You get it.. I have a Weber carb with an aftermarket manual choke which I use to get it started, although it doesn’t seem to help much one way or another. I’ve tried resetting the mixture screw and messing with the idle screw several times with mixed short term results. There are a bunch of vacuum components that have been removed and plugged. Not sure what else to do, been thinking of getting a new carb for it but am open to suggestions!

[banzai510(hainz)]

you sure that choke cable is closing the flap?n when you pull it.  cpuple pumps on the pedal and start. pump it up till gets warm and open the choke once warmed up.

[datzenmike]

Next time engine is cold take top off carburetor air filter. If it has electric choke, pump gas 2-3 times and look. Choke flap should snap closed and engine start normally. When choke flap is closed and engine started, the idle speed should quickly rev up around 2k. As soon as started you should be able to drive away normally. Choke should shut off and fast idle will reduce all by itself

 

If manual choke, pull out lever and look. Choke flap should be closed, engine should start normally and quickly rev up to around 2k. As engine warms up you can reduce the choke and eventually shut off fully as well as the fast idle.

 

What does yours do?????

Does the choke close????

Does the engine rev up on the fast idle?????

[Mmoony]

4 hours ago, datzenmike said:

Next time engine is cold take top off carburetor air filter. If it has electric choke, pump gas 2-3 times and look. Choke flap should snap closed and engine start normally. When choke flap is closed and engine started, the idle speed should quickly rev up around 2k. As soon as started you should be able to drive away normally. Choke should shut off and fast idle will reduce all by itself

 

If manual choke, pull out lever and look. Choke flap should be closed, engine should start normally and quickly rev up to around 2k. As engine warms up you can reduce the choke and eventually shut off fully as well as the fast idle.

 

What does yours do?????

Does the choke close????

Does the engine rev up on the fast idle?????

Got a manual choke, I’ve looked at the choke flap with the air filter taken off. Plates are closed when lever is pulled out. Plates are open when lever is pushed in. I always pull the choke lever before starting. However, I still get the above symptoms. A lot of the time it will run super rough right after starting and I will push the choke lever in which will make it sound a little better but it still dies. Engine doesn’t rev up to fast idle, maybe I should turn the idle screw up? I have to give it gas for the engine to run at first. I have the idle screw turned up to idle at around 1100 rpms

[datzenmike]

No don't adjust the idle screw. The choke should engage a fast idle cam it drops down and prevents the throttle from closing down to the idle speed. When the choke is turned off the fast idle is also removed.

 

When the choke is on the mixture is rich. The fast idle just holds the throttle open slightly and it revs up. This is the fastest way to warm the engine.

 

Now you have a manual choke and perhaps the fast idle is not connected but anyway this video really shows the fast idle cam adjustment about 7 minutes in...