Fast idle on my Eddy Performer 600cfm

[dakonthemountain]

I think I may already know the answer to this, but I wanted you experts to chime in here with your thoughts and ideas. I have rebuilt a few in my younger years, but I am most definitely NOT a carburetor guru. Last summer I put a new 600 (or 650?>>>>?? I forgot!) Edlebrock carb. on Burt and the truck was just screaming smooth when I first put it on. Then I recently set the timing (for the first time in a while, it was quite retarded, but I don't remember how many degrees) and now that the timing is spot on the idle is way too high. I can slow down the idle by advancing the timing, but I can't turn it down with the adjustments on the carburetor any more. the idle screw is as far as it will go. My only other thought is to re-jet it to richen it up a bit. Yes? Everything else is factory specs and perfect except the timing and idle, before and after the new carb. Thanks in advance for your replies!
Ford trucks rule!!!

 

[Mil1ion]

change the adjustment on the fast idle cam

 

[dakonthemountain]

The problem is that there is no more adjustment on it. It's adjusted as far as it will go. ??

 

[Mil1ion]

Not the idle screw.. the fast idle circuit linkage.

what model Eddie ..performer ?

 

[chuck101st]

Could try disconnecting the acc. linkage to see if it is binding somewhere and not letting it come back to idle.

 

[dakonthemountain]

Yes Mil1ion, it is a Performer. I will have to get my diagrams out to see the fast idle linkage and how to change it. My technical knowledge ended there

Chuck101st, It is not binding, I can flip it easily with my fingers. The linkage is smooth

 

[1985 Ford F-150]

You have to open the throttle up all the way with the motor off and youll see the screw. I had the same problem and it turned out to be the electric choke stayin shut so I put a 750 with man choke and its never run better just lack a little in the low low end.

 

[Mil1ion]

Page 9 near the bottom.



http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

 

[dakonthemountain]

Thanks Mil1ion,
I actually have the manual for the carb. In speaking with my buddy (who is a carb guru) It appears that we have already "bottomed out" the adjustment, so tomorrow I am going to the speed shop we use to get a kit to re-jet it. I'll post as to the progress/outcome. Thanks again for all the responses!
Dak

 

[dakonthemountain]

Ok, ordered the jet/metering rod kit. It comes with 3 different sizes. Can't take the time to work on it for another week though After reading the manual more in depth, you guys, and calling Edelbrock technical service I now understand how/what to do. The fast idle circuit linkage is as far as it will go, so this is the only answer, according to Edelbrock. When the parts arrive and it's done I'll report back.

Did I say I like this site?
Dak

 

[johaner78]

Dak, is the idle too fast when the motor is at operating temp OR at cold engine start up? I think Dennis's suggestion only changes the "cold engine" idle speed adjustment, like when you set the automatic choke when you first start the engine.

 

[dakonthemountain]

Your post was very timely.

On Saturday, we went to change the metering rods and jets. Unfortunately, I had left my tools at the mountain house and only was able to go as far as changing the rods. It helped a little bit, so I know we are on the right track and will do the jets in a couple of weeks, when I have the time to remove the air horn to get to the jets, since they really need to be done together. . Oh, and it is only when the truck warms up and the choke shuts off. The idle circuit adjustment screws are fully seated. It runs too rough that way so I backed them off a quarter turn. I'm not driving it until it's fixed though. I'll post when it's done with the specifics.
Dak

 

[Mil1ion]

The idle circuit screws are fully seated ?


Please explain ?

 

[dakonthemountain]

Dennis, Before tearing into the carb, after timing the engine, the only way we could lower the idle speed was to adjust them. The idle speed screw was already at the stop and there was no further adjustment there. Apparently this carb "out of the box" was not made to work all that well on the 460 until further physical adjustments are made, unless you keep the truck timing way retarded, which is what a mechanic did when he installed the carb. The timing was one of the causes of my heat problem and vaporlock in the gas lines. Once we set the timing spot on the idle went up. It has been a slow process of testing/elimination, but we are finally there! (or at least will be after the new jets) At that point we can adjust the idle circuit back to normal. I just left it the way it is for now since I'm not driving Burt until the new jets are in. Hope this makes sense!
Dak