Hot Rods 63 Impala new Edelbrock idle too high

Hey guys I just installed a new Edelbrock 1403 with electric choke. I started it and it idles at 1200 . It should go down with the choke and it didn’t. It sat for a month before being started and today was 70 degrees. I didn’t mess with any of the adjustments until I get more advice. The choke is hooked up to keyed on + and grounded - at the screw housing.

 

The choke isn’t “on” it’s open and the fast idle screw is not on the fast idle cam. It’s purely at 1200rpm on the idle speed screw. If you want to reduce idle speed you need back out the idle screw. If you want the choke to work you need to adjust it related to engine/air temp.

 

The screw in the top left of the first pic is the idle screw. Back that out some.

And read the manual! Don't get hung up on 'tuning', well not yet anyway. Getting it running in the first instance is what's required. Edelbrocks are often lauded as running 'straight out of the box', but don't take that too literally! Some basic adjustment required.

Chris

 

PS if you’ve not even touched the throttle it’s probable the choke is open as it’s jammed on the fast idle cam. Blip the throttle see if it closes.

 

I haven’t touch anything. I need to mention that I have a vacuum gauge. I hooked up the vacuum line to the right but the gauge didn’t show anything. I moved it to the left and it works but on the left instead of the right.

 

Adjustments to choke and throttle blades are going to be needed,
You're gonna have to get the vehicle running ,
Start with backing choke off Not working,
" completely open"
Ajust Idle and enrichment screws @ operating temp.
Check For Va*** leaks. Can of brake clean.
Want's that set ,
Let cool then start setting the choke adjustment,, Covered in paper work .

 

Plug your vacuum ports for now.

A screw in a piece of tubing will plug them.

Edit: Is the adapter in place, I don’t notice it?

 

Just keep in mind that any carb with a choke will have two idle speed adjustments. One is usually called the high-speed or fast idle spec. It comes into play when the choke is set and the engine needs a higher idle speed to keep from stalling and to get the engine warmed up quicker with a richer fuel mixture.

After the engine is up to temperature is when you set hot idle, or sometimes referred to as the curb idle speed. This is when the engine is warmed up, the choke is fully open and the engine no longer needs the richer fuel mixture.

Your vacuum gauge should be connected to a source of full manifold vacuum with the engine at the curb idle speed. The user manual for the carb should indicate which port supplies manifold vacuum and which connection is ported or off-idle vacuum. Typically the full manifold vacuum port will be lower on the carb, usually below the throttle plates. The ported vacuum connection tends to be higher up on the carb, above the throttle plates.

 

As has been said thats your fast idle. On the 1406 I just did, set that screw in your pic until it sits about the middle of the cam its resting on now.
Then you can fine tune from there.
Edelbrock usually includes decent setup instruction paperwork with a new carb.

 

Yeah the adapter is a done deal. The carb is remanufactured . It didn’t come with anything but the carb so instructions. I watched YouTube videos from Edelbrock and they said it should run out of the box. I lowered the fast idle and it only goes to 900. I drove it around and it won’t idle to 500.

 

Disconnect your throttle pedal linkage to rule that out as a cause. If that's good I'd figure out a way to wire the choke flap wide open to rule that out.
Next step would be spraying it to check for vacuum leaks, then hook up your vacuum gauge and adjust your mixture screws to get highest gauge reading.
Everyone else pointed out your idle speed screw so obviously that's the first thing to adjust.

 

Make sure the throttle rod from the car itself isn't holding it open. Sometimes, you have to adjust that too when fitting a new carb to your car.

 

You're typing faster than me

 

Do you have any pictures of the adaptor set up? If the adaptor isn't 100% dead nuts on the sealing surfaces, a vacuum leak will cause high idle. If you backed the idle speed screw all the way out and it still idles over 1000, you likely have a vacuum leak, or your timing is too high.

Shoot some brake cleaner around the carb area to see if you have a vacuum leak, if not, throw a timing light at it. Do those two things, then check back. We'll get this, I promise.

-Abone.

 

@Moriarity @swade41 I started typing my reply, then had to do something upstairs, and finished up later. I think we all thought the same thing at the same time.

 

Installation manual ,
https://static.summitracing.com/global/images/instructions/edl-1221.pdf
Owners manual,
https://www.edelbrock.com/pub/media...7HGcMjqSyvHwQeuvZ2Big6gJB0VQenk7PN8sdjGq5T2DA
Page 8 for choke adjustment in owners manual. Rod "D" needs some adjustment so the fast idle cams backs off more, rod needs to be longer.

 

So bad news. The adapter is a transdapter brand it doesn’t work with my manifold. I’m going to install the old carb because it idles properly. I was able to drive to the shop barely with the ****erfly getting hung up at2k rpm. Anyway the shop said I need to rebuild or replace the motor. So that’s where I’m at. I’m starting a new thread for engine removal in my sloped driveway. Thanks for all the help guys

 

What explanation did the shop give when advising you need an engine rebuild or replacement? They didn't by chance offer to take the car off your hands, did they?

Chris

 

My wife copped a bit of flack on this thread about adaptors being a "hack job" method [ this ^^^ is one of the reasons]
So she deleted all her posts.

Now before you turn your car into a total *********** based on the opinions of somebody commercially motivated, you need to get down to the basics.

You need a vacuum gauge , a compression tester, and a mechanical oil pressure gauge
And go through the basics of checking engine condition.

Your engine seemed to be OK way back when you considered a transmission swap, and power steering swap.
So what has changed.
Connect up the oil pressure gauge to a port and start it .
And compression check it
If a cylinder + is down, then squirt some oil down the bore [if it is still down ,it could be valves]
ALSO back-off the hydraulic lifters until they rattle [on the cylinders that are down] and compression test it again
Also invest in some MSD timing tape for the balancer and get a basic timing light .

DO NOT DO THE DISMANTLE OF DEATH [or a winter project becomes a 10 year project]
If you engine is history [needing a rebuild] Don't rebuild it.

Buy a good runner and swap it in when you pull the old engine out.
I would suggest a late model roller cam 350 with all your peripherals from the 327 [converted to carb]

My money is on the 327 being OK ,but just needing the basics .
You will get no help from a modern shop [all they know how to do is OBD2 diagnostics ,then throw parts at it]

Chevys are simple engines but the knowledge is slowly becoming a forgotten "black art"

 

I had identical problem with a new Holley. One of the throttle plates was not quite centered in its shaft and wasn't closing all the way. Loosened the screws, pushed the throttle plate to fully closed, retightened screws and it worked perfectly.