Just when I think I have my carb dialed in, I don't

[Backfoot100]

I would definitely agree that you need to set the choke before adjusting it.
Adjusting the choke before setting it would make it close tight when you did set it. You don't want that.

I also concur that it isn't unusual to need two pumps to start cold. I always give it two.
The 383 in my boat with a Holley needs two pumps cold.

 

[Matt69olds]

Beat me to it! Definitely need to set the choke before you adjust it. And yes, every carb/truck/car/etc has its own personality, you need to experiment and find out what makes your truck “happy”. There is a reason we refer to our pride and joy vehicles as “she”, your trying to find what makes her happy when “warming her up”. . Your truck will never have a headache!!

 

[MisterB]

Have you seen the video about adjusting an Edelbrock carb with a credit card? Might help you get it dialed in.

[emoji1787]

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[MisterB]

I would definitely agree that you need to set the choke before adjusting it.
Adjusting the choke before setting it would make it close tight when you did set it. You don't want that.

I also concur that it isn't unusual to need two pumps to start cold. I always give it two.
The 383 in my boat with a Holley needs two pumps cold.

And when you say "set the choke" before adjusting, does that mean pump the accelerator once or twice first, leave key to on position so electric choke is getting power, and THEN adjust the choke?

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[88 diesel]

If it were me I would have the filter off w full access to all adjustments and all vacuum lines plugged.
With the engine cold I would adjust the choke to just touch being closed.
I would make sure the accelerator pump is working.
Pump it three times.
Start the engine and see where the choke is right after it starts. Usually open 1/4 + -is adequate.
I would adjust the high speed idle to whatever rpm the engine runs the smoothest. Usually 1k to 1250.
Let the engine warm up without revving it up.
Make sure whatever choke pull off you have is working. Make sure whatever choke heater you have is working. Make sure the high idle cam is working and stepping down as the engine warms up.
If anything isn't working that we went over it must be repaired before moving on.
After the vehicle warms up use your hand to cove the carb slowly to see if it's running rich or lean.
Every engine will need an adjustment that suits that particular engine so use your ears, a vacuum gauge, a tachometer to find the sweet spot and whatever it comes to then there it is. Cold operation w the choke should only be a few minutes of operation. It's much more important to have the carb set at operating temperature.
Some vehicles are very cold blooded and you won't be able to just walk away on cold days til the high idle comes down. It's not new anymore and linkages wear, vacuum leaks, engines loosen up, distributors and timing chain wear.
To drive a classic take patience but I've always been happy to make the trade off.
I wish it was a procedure written on a stone tablet but unfortunately they are all different.
Keep the key off. If you have an electronic choke it will start opening right away and you don't want that til you start it.
Bill

 

[Backfoot100]

And when you say "set the choke" before adjusting, does that mean pump the accelerator once or twice first, leave key to on position so electric choke is getting power, and THEN adjust the choke?

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Just pump the throttle once. That should set the choke. Leave the key off because of its electric choke it will start opening with the key on.
Now adjust the choke like you did before so its just cracked open. Maybe 1/16"-1/8".
After adjusting it you can then start it. If electric choke it should open up on its own in about 45 sec. to a minute maybe.

 

[MisterB]

Just pump the throttle once. That should set the choke. Leave the key off because of its electric choke it will start opening with the key on.
Now adjust the choke like you did before so its just cracked open. Maybe 1/16"-1/8".
After adjusting it you can then start it. If electric choke it should open up on its own in about 45 sec. to a minute maybe.

I don't know what to think anymore. I followed these instructions, but in order to set it like that, the white mark on the electric choke knob must be spun so far to the left that the marker is way to the left of any of the hash marks, and the power and ground plugs are sticking straight up. I figured, "whatever. That's what it's showing", so I tightened the screws and tried starting it. It wouldn't start. Ended up just putting the white mark at the very top left hash mark and it started OK, but who the hell knows if it'll like it until tomorrow morning after it has sat again.

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[Dutch Rutter]

I don't know what to think anymore. I followed these instructions, but in order to set it like that, the white mark on the electric choke knob must be spun so far to the left that the marker is way to the left of any of the hash marks, and the power and ground plugs are sticking straight up. I figured, "whatever. That's what it's showing", so I tightened the screws and tried starting it. It wouldn't start. Ended up just putting the white mark at the very top left hash mark and it started OK, but who the hell knows if it'll like it until tomorrow morning after it has sat again.

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Sounds like something isn't quite right here. If I am reading this correctly. You had to turn the black choke cap to the left (lean) in order to get the choke plates to close (richen)? That cap should act like a thermostat and should only adjust the amount of time the carb stays choked.

Could you post up a picture of the driver's side linkages as well as the passenger side linkages? Also do you know what your pressure your fuel pump it putting out? These Edelbrock carbs are known to be very temperamental if they see more then 6 psi at idle. Adding a pressure regulator with a gauge will give you some more adjustability as well as a way to verify your pressures. Might not be a bad idea to verify your getting a full 12v (when the key is on) to the choke if you have not done so already.

 

[MisterB]

Sounds like something isn't quite right here. If I am reading this correctly. You had to turn the black choke cap to the left (lean) in order to get the choke plates to close (richen)?

Could you post up a picture of the driver's side linkages as well as the passenger side linkages? Also do you know what your pressure your fuel pump it putting out? These Edelbrock carbs are known to be very temperamental if they see more then 6 psi at idle. Adding a pressure regulator with a gauge will give you some more adjustability as well as a way to verify your pressures.

No, what I mean is that I turned it left to open it, and then right to close it until it just touched the credit card, but if I left it at that setting, the white line was way left of the left most hash mark and the truck wouldn't start. So, I adjusted the choke so it's near the left most hash mark, which is a couple to the left of where it was set yesterday.

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[MisterB]

Also, I'm not sure what kind of fuel pressure it's putting out. Also, I have already verified with a light that it gets power to that plug with the key on only. I assume that means it's 12v, but haven't verified with a voltmeter that it's 12

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[Dutch Rutter]

No, what I mean is that I turned it left to open it, and then right to close it until it just touched the credit card, but if I left it at that setting, the white line was way left of the left most hash mark and the truck wouldn't start. So, I adjusted the choke so it's near the left most hash mark, which is a couple to the left of where it was set yesterday.

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Ok, got it. Thanks for clearing they up for me. When I was going through my whole fiasco, The Edelbrock tech kept asking me to make certain that the linkages didn't somehow get bent or bumped around in some way.

Also not saying that what helped me can help everyone but its worth a shot. The usual tell sign you might need one is if your not getting consistency from the carb. The more RPM the higher the PSI your mechanical pump will put out. What will happen if your running too high of pressure is that the pump will push fuel past the needles in the carb which will flood them, tuning around this is such a headache because it is not a constant variable your dealing with.

Edit: Read through the thread: Honestly it sounds like your pretty well where you should be basics wise. Good Vacuum, good operation once warm, good idle quality once warm. I can understand the frustration with things still just refusing to work right.

 

[88 diesel]

Work it backwards and let's see what happens.
If you don't mind trying something new.
If you did everything I described before you have done the basic approach to setting any choke on anything.
Let it warm up. How does it run? Rich or lean? Is the accelerator pump working? Is there mist from unburned fuel? How does it start hot? Do you pump it or do you push the pedal down for more air? These things will tell you if we have a good carb to begin with or we have some leaking gaskets.
Bill

 

[MisterB]

Work it backwards and let's see what happens.
If you don't mind trying something new.
If you did everything I described before you have done the basic approach to setting any choke on anything.
Let it warm up. How does it run? Rich or lean? Is the accelerator pump working? Is there mist from unburned fuel? How does it start hot? Do you pump it or do you push the pedal down for more air? These things will tell you if we have a good carb to begin with or we have some leaking gaskets.
Bill

It runs great once it's warmed up. Hell, it runs great when it's stone cold too, other than the first bit where it stumbles and either dies or continues to stumble until the choke opens more. That's why I adjusted the choke this morning to be more open. I'm hoping that'll fix it.

Once the truck is warmed up, I never have to pump the gas at all until I let it sit overnight. It starts every time without needing to do anything. That said, I decided to buy more carb cleaner and I just got done with a long drive, followed by using the carb cleaner to spray down the choke and the linkages and whatnot real well. I also checked for leaks again by spraying the carb cleaner all around the base of the carb (I already have all new hoses and clamps and I tested those a couple weeks ago so I didn't bother). After that, I hooked up my vacuum gauge and dialed in the idle and fuel mixture screws again just to make sure it was still in the green and running well. I found I was able to adjust the idle down a bit, which I'm glad because the regular idle in park after it's warmed up was a bit high since I adjusted it a few days ago with the vacuum gauge. I suspect getting the truck nice and warm with a long drive, vs just idling until the temp gauge came to normal operating Temps, allowed me to bring idle down, while still staying in the green zone.

Tomorrow morning, I will pump once if Temps are in the 40's. I'll pump twice if in the 20`s or 30's like this morning. I'll turn the key and do nothing else, and see if hopefully everything I did today fixed it

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[88 diesel]

While it is warmed up can you feel the spring holding the choke open?
If not you may have the spring off of the piece it is supposed to be hooked to in the electronic choke itself. That happens. Double check that in the morning and make sure the spring is holding the choke closed. If it is just loose at either time then the electronic part of the choke is not slotted properly on the linkage.
Just a question that needs an answer before we can pin it down.
It might just be a cold blooded monster.
I've had a few. And having worked in dealerships I've seen many brand new vehicles of all types that were hard to dial in perfectly for all seasons without adjusting both winter and summer.
Bill

 

[MisterB]

While it is warmed up can you feel the spring holding the choke open?
If not you may have the spring off of the piece it is supposed to be hooked to in the electronic choke itself. That happens. Double check that in the morning and make sure the spring is holding the choke closed. If it is just loose at either time then the electronic part of the choke is not slotted properly on the linkage.
Just a question that needs an answer before we can pin it down.
It might just be a cold blooded monster.
I've had a few. And having worked in dealerships I've seen many brand new vehicles of all types that were hard to dial in perfectly for all seasons without adjusting both winter and summer.
Bill

I'll check it out and let you know. Thanks

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