Stuck choke?
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New User
Joined: Oct 2011
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Stuck choke?
Whenever I start my truck, it starts at a real high RPM. As soon as I hit the gas though, it drops down to a nice idle. A friend said I may have a stuck choke. However, I found that I have an electric choke. Is there any way troubleshoot this, or should I just get a new carb?
Moderator
Joined: Dec 2007
Posts: 7,987
Likes: 104
From: Boise, Idaho
If the engine's cold, it should be starting at a higher RPM (around 1500 - 1800). This is to help bring the engine up to temp quicker. Then, when you press the gas down and release, it should kick off and idle at a lower RPM (especially when warm).
If your choke was stuck, you'd have high RPMs even once the engine was warmed up, or it'd be sputtering and struggling when it's cold.
To see if your choke is working:
When the engine's completely cold (preferably sitting overnight), before you start it, remove the air cleaner and then press the throttle down all the way and release. The butterfly/choke valve on top should snap shut and leave about a 1/16" - 1/8" opening around the valve.
Now, bring the engine all the way up to operating temperature. The choke valve should be straight up and down. If not, it needs to be adjusted, or the choke spring is weak/broken.
To adjust it, with the engine warm (and even running), loosen the three hold down screws on the back of the carb and rotate the black round choke housing until the choke is fully open.
If your choke is working properly, then spray choke/carb cleaner all over the linkage to be sure it's all clean and freed up.
If your choke was stuck, you'd have high RPMs even once the engine was warmed up, or it'd be sputtering and struggling when it's cold.
To see if your choke is working:
When the engine's completely cold (preferably sitting overnight), before you start it, remove the air cleaner and then press the throttle down all the way and release. The butterfly/choke valve on top should snap shut and leave about a 1/16" - 1/8" opening around the valve.
Now, bring the engine all the way up to operating temperature. The choke valve should be straight up and down. If not, it needs to be adjusted, or the choke spring is weak/broken.
To adjust it, with the engine warm (and even running), loosen the three hold down screws on the back of the carb and rotate the black round choke housing until the choke is fully open.
If your choke is working properly, then spray choke/carb cleaner all over the linkage to be sure it's all clean and freed up.
Junior User
Joined: Nov 2010
Posts: 86
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From: Rust/Salt Belt in SW Mich
77,
If it is running exceedingly fast during choked startup you can adjust the rpm down by turning the screw out that comes into contact with the fast idle cam. This adjustment will not affect your regular idle at all.
If it is running exceedingly fast during choked startup you can adjust the rpm down by turning the screw out that comes into contact with the fast idle cam. This adjustment will not affect your regular idle at all.
5th Wheeling
Joined: Aug 2021
Posts: 46
Likes: 14
From: Monroe, Louisiana
I did as you said and took off the breather. No matter what I did with my accelerator the butterfly would not move. I reached around the carb and pulled the linkage several times wide open but the butterfly didn't move.
New carb time?
New carb time?
FTE Legend
Joined: Nov 2015
Posts: 30,935
Likes: 4,124
From: Angier, NC
Hold the throttle open a little when you try and move the choke what happens then?
If it still dose not move I would remove the carb to check it out better on the bench.
Remove the linkage to the choke and see if it moves then if it still dose not then maybe a new carb but there has to be a reason why you just need to dig deeper.
Dave ----
5th Wheeling
Joined: Aug 2021
Posts: 46
Likes: 14
From: Monroe, Louisiana
I started the truck cold and tried moving the choke **** on the back of the carb by loosening the 3 screws and rotating the **** but it made no difference. Once the truck is warm it purrs like a new truck but starting it cold is a trick. I never revs at start up like it did before and once running it acts very sluggish. I hope to be able to work on it next week and take it off the truck. I guess I should look at rebuild kits?
FTE Legend
Joined: Nov 2015
Posts: 30,935
Likes: 4,124
From: Angier, NC
A rebuild kit is cheap so yea get one as it cant hurt to clean it.
BTW what are we working on year mostly.
Also maybe some pictures might help too.
Dave ----
BTW what are we working on year mostly.
Also maybe some pictures might help too.
Dave ----
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5th Wheeling
Joined: Aug 2021
Posts: 46
Likes: 14
From: Monroe, Louisiana
I found the problem.
I went ahead and bought a new carburetor as I felt like if I bought a rebuild kit and rebuilt the carburetor and that still wasn't the problem. I would have wasted my time and money so I bought a new carburetor and it's running perfect now but I was curious so I started taking the old carburetor apart and found this to be the problem in the choke.
This forum is awesome and I really appreciate everyone who contributed.
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