Think I found my choke problem
Thread Starter
Burning Brakes
Joined: Jul 2006
Posts: 1,108
Likes: 0
From: Sebastian Florida
Think I found my choke problem
It looks like the 'flap' that is supposed to close during a cold start, is sticking open. When the flap is straight up and down, the bottom is sticking to the bottom of the carb. Any ideas?
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Is your choke manual or electric?
When you turn on the ignition the electric choke flap will close over the primaries. A manual choke will close the choke flap anytime the intake/engine is cold and opens as the wound coil element heats up.
Make sure your looking at the choke flap over the primaries and not the air valve over the secondaries (which should be closed anytime the engine off).
Good luck,
cardo0
Make sure your looking at the choke flap over the primaries and not the air valve over the secondaries (which should be closed anytime the engine off).
Good luck,
cardo0
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
When you turn on the ignition the electric choke flap will close over the primaries. A manual choke will close the choke flap anytime the intake/engine is cold and opens as the wound coil element heats up.
Make sure your looking at the choke flap over the primaries and not the air valve over the secondaries (which should be closed anytime the engine off).
Good luck,
cardo0
Make sure your looking at the choke flap over the primaries and not the air valve over the secondaries (which should be closed anytime the engine off).
Good luck,
cardo0
Electric just takes the place of mani X over heat.
Racer
Joined: Feb 2005
Posts: 373
Likes: 1
From: Bayonne NJ
I have a manual choke on my 71. When the car is hot and I try to restart it the choke stays closed and wont let it start. I have to stretch my arms to turn it over and keep the flap open. Would my problem be the coil element being bad???
I figured I'd dig up this old thread instead of starting a new one. Hope you guys are still around.
I figured I'd dig up this old thread instead of starting a new one. Hope you guys are still around.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
If you had a manual choke, you would just set it to the 'open' position and it would start [when hot]. Your '71 has a "divorced" choke, which has a bi-metalic spring that sets the choke in proper position, regardless of the temperature of the engine. That's IF is in good shape and is adjusted properly.
To the OP: If the choke plate is acutally binding up with the carb body, you need to determine why and relieve the cause of the binding. If the mouting bolts are not torqued properly or are torqued down differently, the carb bowl could warp and cause that kind of problem. It could also bind via the choke linkage [rather than a physical binding inside the carb body]. Your best chance of correction is to follow the carb/choke set-up instructions/procedures in the Chevrolet Chassis Service Manual [Section 6M, Fuel System].
To the OP: If the choke plate is acutally binding up with the carb body, you need to determine why and relieve the cause of the binding. If the mouting bolts are not torqued properly or are torqued down differently, the carb bowl could warp and cause that kind of problem. It could also bind via the choke linkage [rather than a physical binding inside the carb body]. Your best chance of correction is to follow the carb/choke set-up instructions/procedures in the Chevrolet Chassis Service Manual [Section 6M, Fuel System].
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
Could be, it's easy to check.
The arm on the choke should press straight down to the 'stop', this is where the arm should be when the choke is cold. When it is hot, the arm should extend upward opening the flap open.
So, when the choke is hot - will does the arm have motion to get in the 'stop' position?
Matt
The arm on the choke should press straight down to the 'stop', this is where the arm should be when the choke is cold. When it is hot, the arm should extend upward opening the flap open.
So, when the choke is hot - will does the arm have motion to get in the 'stop' position?
Matt
Racer
Joined: Feb 2005
Posts: 373
Likes: 1
From: Bayonne NJ
hmmmmm.... All good information. I just picked the car up a couple months ago so i haven't really looked it over or driven it too much. I have to look at the whole setup. Today was in the 60's here, so I washed all the dust off it an took it for a spin. It ran great other then this issue. It doesn't seem to be binding. The choke operates freely. I just hold it open as i streeeeech to turn the key. Once it turns over I can take my finger off the flap and its good to go ( until the next hot start)
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Brett Foote
Intermediate
Joined: Dec 2009
Posts: 47
Likes: 0
I know it sounds bad but I was having choke fits with my 76 after I got it and finally discovered the spring in the choke thermostat was installed backwards. I was getting tired of that stretch you're talking about so I took the thermostat off and discovered the spring turned so that it was actually closing the choke more as it would expand rather than opening it.After starting the vacuum pulloff would hold it open. Bubba has been everywhere in my car.....
Racer
Joined: Feb 2005
Posts: 373
Likes: 1
From: Bayonne NJ
So today I finally got around to looking at my choke set up.
The coil itself was linked to the choke arm with what looks like a clothes hanger??? (it is disconnected in this pic).
The arm that Im holding the key to seems to hold the choke open in the position that it is in. I dont know what tells this arm to close the choke, because it gets hung up at this position, but if i push the arm it will pass that point and the choke will go full closed.
I hope you guys are keeping up with me here ( Im confused so my thoughts are coming across jumbled).
Is there something that Im missing?? I dont have the manual so im not sure. It seems that the coil spring would hold it in the position by temperature, and once started the vacuum would hold it open.... So why is that arm hanging up????? IDK, hopefully something in this post made sense.......
The coil itself was linked to the choke arm with what looks like a clothes hanger??? (it is disconnected in this pic).
The arm that Im holding the key to seems to hold the choke open in the position that it is in. I dont know what tells this arm to close the choke, because it gets hung up at this position, but if i push the arm it will pass that point and the choke will go full closed.
I hope you guys are keeping up with me here ( Im confused so my thoughts are coming across jumbled).
Is there something that Im missing?? I dont have the manual so im not sure. It seems that the coil spring would hold it in the position by temperature, and once started the vacuum would hold it open.... So why is that arm hanging up????? IDK, hopefully something in this post made sense.......
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
So today I finally got around to looking at my choke set up.
The coil itself was linked to the choke arm with what looks like a clothes hanger??? (it is disconnected in this pic).
The arm that Im holding the key to seems to hold the choke open in the position that it is in. I dont know what tells this arm to close the choke, because it gets hung up at this position, but if i push the arm it will pass that point and the choke will go full closed.
I hope you guys are keeping up with me here ( Im confused so my thoughts are coming across jumbled).
Is there something that Im missing?? I dont have the manual so im not sure. It seems that the coil spring would hold it in the position by temperature, and once started the vacuum would hold it open.... So why is that arm hanging up????? IDK, hopefully something in this post made sense.......
The coil itself was linked to the choke arm with what looks like a clothes hanger??? (it is disconnected in this pic).
The arm that Im holding the key to seems to hold the choke open in the position that it is in. I dont know what tells this arm to close the choke, because it gets hung up at this position, but if i push the arm it will pass that point and the choke will go full closed.
I hope you guys are keeping up with me here ( Im confused so my thoughts are coming across jumbled).
Is there something that Im missing?? I dont have the manual so im not sure. It seems that the coil spring would hold it in the position by temperature, and once started the vacuum would hold it open.... So why is that arm hanging up????? IDK, hopefully something in this post made sense.......
Tech Contributor
Joined: Aug 1999
Posts: 14,377
Likes: 6,377
From: At my Bar drinking and wrenching in Lafayette Colorado
Yup. The coil is backwards. Put the coil the right way and get the right linkage parts for it. Then adjust your choke as outlined in my paper.
Lars
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Lars, I took my '80 L48 for a spin today. 1st since last fall. Other than a pesky ignition/charging issue (it wouldn't start without a jump when I stopped for gas), the carb that you rebuilt back when I lived in FL performed flawlessly. That was probably close to 2000... ten years ago.
Lars, I hope all is well with you and that you are still tuning/rebuilding!
Tech Contributor
Joined: Aug 1999
Posts: 14,377
Likes: 6,377
From: At my Bar drinking and wrenching in Lafayette Colorado
Please note that it was Paul who spotted the error. I simply agreed with him and confirmed his observation. Paul and I have been trading tech info for several years, and he's as technically astute on this stuff as I am.
Lars
Lars
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Sorry Lars, 'had one too many cold ones while I was getting the C3 out of hibernation today (if that is possible). Didn't mean to give cred' inappropriately.
Racer
Joined: Feb 2005
Posts: 373
Likes: 1
From: Bayonne NJ
Pwcheenie... PM me if you still need a better picture of the part we are talking about.
Lars>> Where do you order your parts from? I dont know the linkage piece i am looking for so i cant find a company that carries the part that i need....
Lars>> Where do you order your parts from? I dont know the linkage piece i am looking for so i cant find a company that carries the part that i need....
