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Discussion Starter #1
I was hoping to get some help from some experienced folks. I searched the forums and couldn't find anything similar to my issue so I thought I'd see if one of you may have an answer.

I have 69 Camaro, 350, Edelbrock RPM heads, Lunati 268 cam, Air Gap Intake, Pertronix ignition, headers, and a 670 Street Avenger. I've always had issues with the idle but got those resolved with a new power valve. This is the issue I'm having:

The car has a 670 Street Avenger, electric choke. The choke setting is to the right of the center. When I crank the car, it fires right up and idles at 1500 rpm, just like it's supposed to. But when I drive it around for 10 miles or so, the car is idling around 1000 rpm and the fast idle cam is still engaged. I can push it down and then it idles around 750, which is what I want.

I talked to Holley about this and we verified I have 12 volts going to the electric choke (power from the windshield wipers). Holley said there was too much pressure on the spring and advised me to pull the two stop pins out, loosen the three screws on the choke, hold the throttle open over 1/2 way, turn the choke until the choke plate is fully open, and the back it back until it shuts. Then tighten the screws.

I did this and the car started with me holding the accelerator open. After I got the car warmed up and let off the gas, the fast idle cam dropped off but the car now idles at 500 rpm. I couldn't live with this without having a choke. So I called Holley back and they told me to move it 1/2 way between where I originally had it set and the new spot. I did this. The car cranked up, choke engaged, but idles at 1200 rpm instead of 1500. And when it warmed up sufficiently, I reved the motor and the idle dropped to 1000 with the fast idle cam still engaged. When I pushed the fast idle cam down, the idle dropped to 600 rpm.

I know this is lengthy, but I'm hoping to gain from some of your experiences. Any thoughts on what may be wrong? It appears that if I want to have some semblance of choke, the fast idle is going to stick.

Any help on fixing this carb would be appreciated.

Rick
duskblue69
 

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I've had problems with holley's choke lever mechanism binding up behind the choke housing. I'd remove the electric choke spring assembly so the mechanism can move freely. Then prop the throttle plates open slightly so the fast idle screw doesn't interfere with the fast idle cam. Then with your finger, fiddle around with the choke plate and the weighted fast idle cam to make sure it easily moves and doesn't bind up. You might want to pay particular attention to the side to side motion of the choke plate. It may be that if the choke plate slides slightly to one side or another that binding occurrs. If you find any binding, usually a slight bending of the choke rod with a screwdriver is all it takes to get things right.

The only other thing I can think of that may cause choke problems is a missing doghnut gasket between the choke housing and the main body. There is a tiny vacuum passage that draws air through the choke housing to cool the heated spring and suck open the choke plates the moment the engine starts. If that gasket was missing or misaligned, it may not be pulling the choke open properly.

Don't be surprised that once you find the problem, you may have to readjust your fast idle setting and choke setting. Carb issues often lead to adjustments to compensate for a problem that'll leave you off in the weeds once you get things right.
 

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Discussion Starter #3
Dave,

I tried your suggestion of removing the choke spring and moving the choke plate. I move it from side to side. I moved the part that goes into the choke spring back and forth. There was never an issue with the fast idle cam. It moved freely also.

Maybe this is supposed to work this way, but when I put the choke spring back on and started turning it clockwise, the fast idle cam raised slightly and then dropped when I got it to the point that the choke plate opened fully.

I'm beginning to wonder if there is an issue with the choke spring. I guess I'll look at it again tomorrow. Today is a family day after all. Thanks for the suggestions.

Rick
 

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That's interesting. As you can imagine, the farther you turn the choke spring clockwise, the stronger the spring force on the choke plate should be and the fast idle cam as well. Is there any chance you didn't engage the spring with the tab inside the housing and it slipped off? Otherwise, I wonder if a linkage behind the choke housing isn't isntalled correctly. In any event what you found is not normal.
 

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Discussion Starter #5
Dave,

I pulled off the choke housing and made sure that rod from the choke plate is in the coil housing.

Interesting enough, last night I let the car warm up for about 15 minutes. I took the breather off so I could look at it. The idle was around 1500 rpm. When I revved the engine, the idle dropped to 1000 and the fast idle cam was still engaged. When I pushed the cam down, the idle dropped to 750 rpm.

When I moved the throttle about an inch, the rpms went up, the fast idle cam moved up, and the choke plate moved forward just a little. I tried revving it up and the fast idle cam didn't fall off. I tried this scenario a few more times and got the same result. It has to be something small.

I spoke with Holley and they said they would send out a new choke cap and I'll try that first. If that doesn't do the trick, I'll have to send the carb back to them for them to check out.

Any ideas?

Rick
 
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