Another won't start thread
Thread Starter
Racer
Joined: Nov 2011
Posts: 374
Likes: 21
From: Charleston SC
Another won't start thread
Used to have no problem starting. Hot, cold, warm - made no difference: start right up. Recently, have had to floor accelerator, hold it, crank until it finally fired, half throttle until it ran smooth and would drive great. Until I shut it down. Then same thing. I saw that the choke flaps were staying closed until it warmed up a bit, then they would open a bit until it started running fairly smooth, then open all the way (vertical). This morning I stuck the clothespin and she fired (thankfully, it really didn't "fire" up) right up and ran great. I'd plugged all the vacuum ports, except the ones I'm using. I hadn't made any adjustments or changed anything I can think of. All helpful ideas will be greatly appreciated. Have a great weekend, Bill
Instructor
Joined: May 2007
Posts: 149
Likes: 7
From: Arkansas City Kansas
Can't see your choke it is on the other side. But sounds like it needs to be adjusted. If it is the spring type under a black cap loosen the three screws and turn it until the choke begins to open. Depending on temp you will need to adjust it to what works best for your car. Some carbs had a vacuum pot that pulls the choke partially open after it starts. If yours has one this could be bad or miss adjusted. The reason it will start when it is wide open is the linkage will pull it open kind of a anti flood stage. A photo of the other side of the carb might help see what type of choke you have.
Instructor
Joined: May 2007
Posts: 149
Likes: 7
From: Arkansas City Kansas
You have the old style choke with the heat coil spring in the intake. It is obviously working as it is pulling the choke closed. You have a vacuum choke pull off that if working properly will pull the choke open after engine starts. I would say this is your problem. Possible bad diaphram but they are replaceable. You can test it by removing the vacuum hose pushing in the plunger then plug the port and see if it stays in. If bad you can get one at most parts stores.
Thread Starter
Racer
Joined: Nov 2011
Posts: 374
Likes: 21
From: Charleston SC
Thanks for the replies. I checked the diaphragm and it passed. The flaps still don't open at all unless I crack them open manually, then she'll run like a swiss watch. Well, maybe a Timex. just a thought, does it matter what port I hook the diaphragm to? Have a wonnerful weekend, Bill
Racer
Joined: Mar 2014
Posts: 316
Likes: 39
From: Machesney Park IL
When she starts, the choke flap should open like picture 2. When starting, the choke should be fully closed, then if it seems flooded, that is why you floor it while cranking, to clear the flooding. We know your electric choke is working, as its closed. It warms up a bit, flap opens some, then warmed up, it is fully off. This is good. Now for the choke pull off. When the car starts cold, it should look like the second pic. You could put a hand vacuum pump on the pull off and check with car off.
Instructor
Joined: May 2007
Posts: 149
Likes: 7
From: Arkansas City Kansas
Has all the symptoms of a bad choke pull off. Pin open the choke and start the car and see if the pull off retracts and stays retracted. Should have full manifold vacuum. Not sure of your year but Autozone has these for around 14 bucks.
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Instructor
Joined: May 2007
Posts: 149
Likes: 7
From: Arkansas City Kansas
I suppose you could have a terrible vacuum leak somewhere affecting the function of the choke pull off. But the car would run very badly after it starts. Certainly would not run like a timex.
Thread Starter
Racer
Joined: Nov 2011
Posts: 374
Likes: 21
From: Charleston SC
Closure
I don't know 'bout y'all, but I hate it when a "I've got a problem" thread is abandoned without closure. I'm probably as guilty as anyone, but not this time! BINGO!!! I'd like to say it was the choke system, but no. "Diehrd" hit the closest to home. Flooding. I definitely should have explored more than I did, but WTH. The gas smell (did I mention that???) should have alerted me if nothing else. After tearing the carb apart for the third time, I replaced the float and all is good. This one, it seems, is a shade narrower than the other. No sticking whatsoever. The other had worked pretty good for quite a while so I didn't expect it to be bad. Again thanks to all and have a great week, Bill