Another Edelbrock issue

[6768chevylover]

I've been reading post about edelbrock 600 carbs.. Of course I have a 1406 carb with the electric choke and my issues are similar to the ones I read with the high idle in the cold but no one seems to have the high idle even when they come to a stop when the truck is warmed up. I'm always bumping the throttle to bring it down and sometimes that doesn't work. When I do bump it I always smell gas. I've also noticed that sometimes when I need to get going when I'm driving, I feel hesitation and then it just opens up. Its an older carb and my first time owning an edelbrock. I usually have holley carbs. Any thing I should be looking for?

[swb4me]

You didn't state the year, so we don't know if you have a throttle cable or rods. When it's running "high" is the throttle plate fully closed or is something keeping it from closing all the way? It could be as simple as the return spring isn't strong enough.

[slowcpe]

You can adjust the choke. I had to do that on mine once it got cold.

[demian5]

Ok - check this out.

I have a friend with a 70 camaro, 350 4-speed, hes had it since new. At one time he had it restored and they redid the engine and trans and put a cam, aluminum intake, headers, holley carb. He said ever since then, the car wouldn't idle right when cold, and when the cold issue was handled, it would die when hot.

It came to me when it wouldn't idle at all hot or cold. Found a leaking rear float. Replaced it. Ran great when hot but you had to deal with it being "cold blooded" I told him (as I was wrapping it up). However, I decide to hold onto the car for another morning to dive into the choke and carb idle issue as well, as it appeared the choke was "hanging up" and not opening completely.

Not hanging up on the air cleaner, lubed the linkage and plastic idle arm and some times ok other times, no good. Tested ground and voltage at the choke, maybe the aluminum intake was not grounded? 6.8v at the choke wire.

Bingo.

The distributor was still OG style points with a coil with the choke wire coming of of the coil terminal. Ran a new wire from the fuse box to the choke, bam - solved.

This car in 70 came factory with a the temp spring mechanical type (divorced?) choke - didn't need 12v...

[68 P.O.S.]

Need your truck particulars. What year is your truck? Which engine is in it? Stock engine or beefed up? Points or HEI? Any recent work done to it that may affect the problem you have? Have you checked for vacuum leaks? Checked your fuel system for clogged filter or sending unit sock, kinked or worn lines, and fuel pump ok?

How’s your timing? If it’s not set correctly before you start working on everything else, you’ll be chasing your tail.

Edelbrock carbs are known to be a little finicky and are not exactly plug n play out of the box (what carb is?). Once setup correctly, they are a great carb. If it’s an older carb, it’s probably a good idea to clean it out real well and rebuild it. Then adjust float levels to specs, add a heat insulating gasket between intake and carb to stop carb boil, add a Edelbrock fuel pump or a fuel pressure regulator set to 5.5 psi to prevent flooding, set the transition slots to square, buy a calibration kit to dial in jetting/rods/step-up springs, and enjoy.

[rockyrivermark]

There are several adjustments for a 1406
I have one and works great
Choke and high idle set points are all adjustable very easily.
Take it to a mechanic and they can set it up for you.

[bigmac73]

I fought one for a long time on an old Dodge 440 , changed rods, springs etc etc. Finally just swapped it for an 850 Holley DP, adjusted idle and Mix screws and no problem (I always keep the manual choke wired open never used it )

[6768chevylover]

Its a 71 c10,350 l31 heads, mild cam,hei, no work recently on it and ill check some of the things you guys mentioned. thanks It just got cold and it started doing this. I actually bumped down the fuel pressure from 5.5 to 4.5 and that didn't do anything. I'm just guessing its the choke cause everytime I come to a stop and press on the clutch the idle rises and then ill bump the throttle and it goes down then a few seconds later you can hear it rise again.

[geezer#99]

Just adjust the choke a tiny bit leaner.
Problem solved!

[fdbdw]

2 usual suspects with Edelbrock carbs fuel pressure and float settings, Edelbrocks are super finicky when it comes to those. Sounds like you’ve checked the fuel pressure, you should check your float settings next. It’s easy to do just follow the manuals directions, can probably find it on their website. It’s also a safety issue cause you can get gas over flowing onto a hot manifold. There are different opinions on whether Edelbrocks are good carbs or not, I’ve had them and have been happy with them I have a Holley now and I’m happy with it. You just need to learn how a particular brand works and how to adjust them.
Correct springs and/or rods for your application can be a culprit but I wouldn’t be surprised if it was the floats condition or settings

[HO455]

I have the same carb as you do. First I suggest you download the manual from Edlebrock's website and familiarize yourself with the choke components. The choke coil on the passenger side of the carburetor operates the fast idle parts on the drivers side of the carburetor. You may be missing a piece or things may just be cruded up. Once you are satisfied the linkage works as designed set it to the specifications in the manual for a base line. Check to see that you have 12 volts at the choke coil and that the ground wire on the choke coil is hooked to a good ground.
Then drive the truck and see how it works. It is likely you may have to make some adjustments. Don't get frustrated if adjusting it to perfection takes a half down or more tries. When setting up a choke I will make an adjustment before I leave work, then I drive home and back to work, giving me two cold starts to compare and decide what the next adjustment will be if I am not satisfied.
The idle may be too high or low for the average temperature of your cold start.
The choke plate may need to be open or closed a little bit more to get the engine to run without stumbling on moderate acceleration.
Ideally you want the fast idle screw to be sitting in middle of the fast idle cam with the temperature in the 45-55 degrees range. But this not a hard fast rule just something I have found to work living in Portland. Another thing I have found is that the Edlebrock electric choke coils take too long to get up to temperature. At least for my taste.
I hope this helps.

[Andy4639]

Well mine works great after adjusting it by a good mechanic friend. The choke was hanging up on it and as described eralier once it was fixed with some tweaking and choke set cold + the 12 volts I can't ask for a better carb and the gas mileage is good to.

[68 P.O.S.]

No carb is ready out of the box. It might be close and run well, but every carb needs to be setup for your specific engine. Improper tuning is the main reason a lot of people say certain carbs are junk.

So you’re saying that even when driving the truck, the choke stays on? If so, sounds to me like it's hanging up somewhere and you need to spray it with some carb cleaner to clean it up. Can you post a couple pics of your choke and linkage to help us see what’s going on there? The fast idle screw needs to be set at 1500 rpm when the choke is on and engine fully warmed up. When you start it, the choke coil slowly warms up, and as it does, the fast idle speed increases in proportion to it. The way I set the fast idle is to allow the engine to fully warm up with the choke on, then check the rpms and adjust it so it’s at 1500 rpm when fully warmed up. It also sounds like you need to adjust the choke a little leaner. The choke needs its own dedicated power wire as well…no daisy chaining, especially off of the HEI or you’ll have problems.

The hesitation you feel could be caused by either the accelerator pump, the step-up springs, or the transitions slots not being set right. You may need to buy a new accelerator pump as the rubber plunger may have gone bad on you. Also, since your engine doesn’t sound too crazy, the accelerator pump linkage adjuster needs to be in the center hole of the 3 to start out. For the step-up springs, how much vacuum does your engine produce at idle? The step-up spring rating should be half of what your vacuum is. So if you’re pulling 10” of vacuum at idle, you need to put in the step-up springs rated for 5”. If pulling 16” of vacuum, or more at idle, go with the spring rated for 8”. For the transitions slots, the carb will need to be pulled and the actual slots need to be adjusted to form a square. This ensures proper operation of each circuit in the carb for proper fuel delivery. Here’s a good little video from Jegs on setting up the carb https://www.youtube.com/watch?v=wR_AfQjyT-A&t=2s

Make sure you check your timing before doing the carb, or all that work will be for naught.

[6768chevylover]

I'm just gonna do a rebuild on the carb.. question, Are the floats on a 750 the same size as a 600? I have a 750 laying around and just in case I have a bad float, I'd like to be prepared.

[68 P.O.S.]

Yes, the floats are the same. Part #1469. I recommend getting a calibration kit also.

[6768chevylover]

Thanks for the info. I plan on doing everything you mentioned in your last post. Thanks again...

[68 P.O.S.]

You make any progress on this?

[demian5]

Originally Posted by 6768chevylover

Thanks for the info. I plan on doing everything you mentioned in your last post. Thanks again...

Did you even check for 12 volts at the choke wire before committing to about $200 in parts and time?

[special-K]

Did you ever come back to tell your results to those who put their effort into helping you? Maybe you just haven't gotten to it yet, but be sure to let those who have helped know and to help all those with similar issues in the future when they did this thread up in a search

[rockyrivermark]

Originally Posted by geezer#99

Just adjust the choke a tiny bit leaner.
Problem solved!

Yep. They are a great carb. Just need a slight adjustment.
Easy to do and only takes 10 min to get it adjusted.

[6768chevylover]

Sorry guys I just got around to doing work on it last weekend. I cleaned the carb adjusted a couple rods and jets and springs and still having the same issue. Yes, I have 12volts to choke, its coming from my fuse panel in a spare spot. I have a feeling I'm having fuel pump failure. Either that or the pump rod is worn down. I still have issues going up hill and accelerating. I've checked my plugs and can see its lean. I have some white on the electrodes and some with carbon build up(makes no sense to me). So i'm gonna buy new plugs wires and a pump. I'll get back to yas on results..

[67ChevyRedneck]

I'm actually having the same issue with mine this winter. My 1406 has been on the truck since 2002. It's been rebuilt once, loooong time ago. When temps are below 50-ish it never fully idles down, it sticks to a few hundred above where I want it. Above 50/60* and it operates normally. This is the first time I've ever had issues with the choke, I think it's time to rebuild mine again.

[Steeveedee]

Originally Posted by 67ChevyRedneck

I'm actually having the same issue with mine this winter. My 1406 has been on the truck since 2002. It's been rebuilt once, loooong time ago. When temps are below 50-ish it never fully idles down, it sticks to a few hundred above where I want it. Above 50/60* and it operates normally. This is the first time I've ever had issues with the choke, I think it's time to rebuild mine again.

Check your throttle shafts. I'll bet they are leaking vacuum unless you have had bushings installed in the body of the carburetor.

[67ChevyRedneck]

Crap, no. I hadn't thought of that. It does have a lot of miles on it.

Would I be able to feel a little pull, or do I need to spray carb cleaner to check?

[demian5]

Originally Posted by 67ChevyRedneck

I'm actually having the same issue with mine this winter. My 1406 has been on the truck since 2002. It's been rebuilt once, loooong time ago. When temps are below 50-ish it never fully idles down, it sticks to a few hundred above where I want it. Above 50/60* and it operates normally. This is the first time I've ever had issues with the choke, I think it's time to rebuild mine again.

Does it have an electric choke or one with the spring and rod attached to the manifold (divorced choke)?

If it has the divorced choke, do you have a working exhaust crossover that heats up the manifold or is it blocked off? If it doesn't have one, it could never be getting hot enough to release the choke fully.