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Fast idle solenoid for AFB/Edelbrock...

YY1

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...that's NOT $200.

https://www.amazon.com/Edelbrock-8059-CARB-COMPONENTS/dp/B00062YCWY

That's what they want at Summit.
Fount it on Amazon for $165, but that's still a little rich for me (see what I did, carb humor).

Ideally I'd love to find one that would work on my factory 2 barrel and then be able to port over to the Eddy AFB/AVS possibly on a different bracket.

My car runs fine, but tends to get hot with the AC on and holding the idle higher with the pedal or putting it in N while stopped in traffic seems to help.

I've thought about junkyarding one but not real sure how to tell a high idle solenoid from an idle stop one.
 
I believe that the two are synonymous, just wired differently. The idle stop solenoid/anti diesel solenoid is wired to extend when the ignition is on. The same device could be wired to the A/C clutch coil circuit to extend when the compressor clutch is energized increasing idle speed. Just my opinion of course.
BOB RENTON
 
I was wondering specifically-

That the idle stop is designed to apply only momentarily at the moment of ignition turn off, whereas the high idle is designed to be applied constantly whenever the compressor is on-

if the coils were rated for momentary versus continuous duty.

That is certainly a consideration in other solenoid applications.

Continuous current to a momentary coil "lets the smoke out" real fast.
 
The idle stop/anti-diesel solenoid is energized (plunger extended) continuously with the ignition is on. The purpose was to increase the idle speed to allow for "cleaner" emissions. But the higher idle speed, in addition to leaner fuel mixtures and retarded timing resulted in dieseling or after run when shutting down. The RPM drop was significant...perhaps as much as 250 RPM from 800 RPM (solenoid energized) to say, 500 RPM, closing the throttle plates to almost closed.
The solenoid coil is rated for continuous duty. The device could be used to increase the idle speed when the A/C system is rnergized (compressor clutch coil). With the new cars with the on board computer controlling just about everything, it automatically increases the idle speed, via the throttle control system (drive by wire), every time the A/C system clutch is energized. There is no dieseling because the fuel and ignition is turned off upon shutdown.
In response to your last comment, it deals with both the magnetic circuit and the in rush current. If the solenoid coil's armature (the moving part) cannot seat (or extend), resulting in the in rush current remaining high, causing an over heat condition and ultimately a failure of the coil ("letting the smoke out" as you noted). Similarly to an electric motor failure when the shaft cannot be allowed to turn or if a 3 phase motor is "single phased".
BOB RENTON
 
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...that's NOT $200.

https://www.amazon.com/Edelbrock-8059-CARB-COMPONENTS/dp/B00062YCWY

That's what they want at Summit.
Fount it on Amazon for $165, but that's still a little rich for me (see what I did, carb humor).

Ideally I'd love to find one that would work on my factory 2 barrel and then be able to port over to the Eddy AFB/AVS possibly on a different bracket.

My car runs fine, but tends to get hot with the AC on and holding the idle higher with the pedal or putting it in N while stopped in traffic seems to help.

I've thought about junkyarding one but not real sure how to tell a high idle solenoid from an idle stop one.
You should start a wanted thread.
 
@RJRENTON

Nice write up. Would you know if the Edelbrock unit is rated for continuous duty?

Thank you....I would think that the solenoid coil would have a continuous duty rating but, I have no experience with that particular item. I know the fast idle/anti-diesel assembly on my RS23V0A***** GTX is the origional solenoid made by Delco and after 50 years still works great. Its been energized for hours at a time especially when cruising Woodward Avenue in Detroit on 90°+ days without issue.
BOB RENTON
 
Thanks again. I’m wondering what to do for my SB 6 pack.
 
@RJRENTON

Why would they use a solenoid to continuously increase the idle speed?

Why not simply specify a higher speed with the mechanical adjustment?

The idle stop solenoids I am familiar with only provide a kick open of the throttle at shut off.

You can do this manually if you have a dieseling problem- pretty well known "back in the day".
 
@RJRENTON

Why would they use a solenoid to continuously increase the idle speed?
MOPAR and other manufacturers used higher idle speeds, combined with lean idle mixtures snd retarted timing to increase exhaust temps to lessen the HC and CO emissions but allowed for the possibility of dieseling. To reduce the chance of dieseling the idle stop solenoid was added to REDUCE the throttle opening to almost closed upon shut down, eliminating or drastically reducing the dieseling. THIS SOLENOID IS CONSIDERED AN ANTI-DIESELING DEVICE NOT A "KICK OPEN" DEVICE AS YOU SUGGESTED, IN FACT JUST THE OPPOSITE.
Why not simply specify a higher speed with the mechanical adjustment?
How do you do that and not promote a possible dieseling event? The solenoid does both ...high idle speed but no dieseling.
The idle stop solenoids I am familiar with only provide a kick open of the throttle at shut off.
See the first response above
You can do this manually if you have a dieseling problem- pretty well known "back in the day".
Yes you can but why can it be done automatically. Turning off the engine in gear or simply letting out the clutch in gear works but why?
There are several ways to do things.....this is just the method that the manufacturers used (anti-dieseling solenoid). Just my opinion of course.
BOB RENTON
 
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I bet that's a bitch to adjust if you have to disconnect the solenoid to adjust the mechanical stop RPM then adjust the solenoid enhanced RPM that basically renders the normal/mechanical one superfluous.
 
So back to the OP's (er, uh, my) question-

Is there a realistically priced or U-pull sourced high idle solenoid that's an easy adaptation to both a stock BBD type 2 barrel carb and/or an AFB type carb?
 
I bet that's a bitch to adjust if you have to disconnect the solenoid to adjust the mechanical stop RPM then adjust the solenoid enhanced RPM that basically renders the normal/mechanical one superfluous.

No....not at all. You would adjust the high idle speed first with the solenoid plunger extended (coil energized). Then de-energize the solenoid (disconnect the wire) set the low idle speed with the carb's idle screw.
On my RS23VOA GTX the high idle adjustment screw is on the carb as well as low idle adjustment screw. Once each is set, everything is ok. BTW...because of my cam (Crane = to Mopar's 292° 0.509" lift with Crane's 1.6 ratio roller rockers) the engine's hot (high) RPM IS ~ 1300 with the solenoid plunger extended and ~ 700 RPM with the solenoid de-energized. And everything works just fine.
BOB RENTON
 
So can we agree that six pack carbs don't apply here?

is the mechanical idle ever in use?
 
So can we agree that six pack carbs don't apply here?

is the mechanical idle ever in use?
ONLY when the ignition is off. I'm not sure what to recommend for Carter BBD application, nor for a AFB. The Carter AVS, 1969-1970 era, used a hot idle solenoid with a special mounting bracket, but don't think its adaptable to an AFB design but perhaps you could mofify it to fit your application....just a thought or maybe Edelbrock psrt could be something that could be used. Or try Tony's Parts....he may be able to help.
www.tonysparts.com
Or consider Scott Smith at Harm's Automotive at: www.harmsautomotive.com
HARMS AUTOMOTIVE LLC
9807 E. BROADWAY AVE.
SPOKANE VALLEY, WA 99206

[email protected]m
Call or Text 801-940-2689

BOB RENTON
 
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OK, back to the original topic-

Here's the $200 offering from Edelbrock.

eddy idle sol.png


Can anyone spot the serious design flaw?
 
So I bought this solenoid from ebay for about $45.


It's advertised as a idle stop solenoid, but notice how it looks virtually identical to the solenoid in the Edelbrock photo.

generic idle.jpg
 
My plan is to fabricate a bracket from a length of angle iron.

The challenge is the diameter of the hole.

I measured the threaded portion of the solenoid at 7/8".

I'm not sure I want to deal with trying to get the flat spot.
That seems like a LOT of work.
Hopefully tightening the nut will work.

I found a set of "Silver and Demming" large size drill bits on ebay.
Supposedly cobalt, but I have my doubts at $32 and free shipping for an index that starts at 9/16 and goes to 1".

bits.jpg


However, even buying that, I'm still WAY under the $200 Edelbrock price, plus I now have a set of large drill bits.
 
So, after using the bits I will say that about every other one I used (progressively larger but skipping the 16th sizes) struggled.

3 of them cut a nice chip, and 3 of them needed fairly hard pressure and smoked a bit, requiring frequently backing off.

They did the job, though and I don't think I burnt any.
 
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