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Old 08-05-2011, 06:07 PM   #1
HarrisonTX
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Carb swap: What is this?

Ugh. I'm swapping my edelbrock for a fresh Holley Truck avenger.

The old carb has some sort of switch on it, and I dont know what it did, but it was hooked up, and the holley dosnt have provisions for that switch.

This vaccumm canister is also in the way of a vaccum port on the holley.



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Old 08-05-2011, 10:39 PM   #2
russgt
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Re: Carb swap: What is this?

The first one looks like a fast idle, the second is the egr valve (emissions)
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Old 08-05-2011, 10:55 PM   #3
Zoomad75
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Re: Carb swap: What is this?

The item on your q-jet is an idle solenoid. On a/c equipped trucks its purpose was to kick the idle speed up to keep the engine from stalling due to the load of the a/c compressor. Another use was to set the curb idle with it energized (powered up with key in run position) instead of the normal idle speed screw. This allows the idle speed to be set and when the engine is shut off the throttle closes completely so that it can't diesel or run on.

The other "vacuum canister" is your EGR valve. If it's in the way you can remove it. You will need to block off the port in the manifold or you'll have exhaust blowing right on to the carb.
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Old 08-06-2011, 01:31 PM   #4
HarrisonTX
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Re: Carb swap: What is this?

Quote:
Originally Posted by Zoomad75 View Post
The item on your q-jet is an idle solenoid. On a/c equipped trucks its purpose was to kick the idle speed up to keep the engine from stalling due to the load of the a/c compressor. Another use was to set the curb idle with it energized (powered up with key in run position) instead of the normal idle speed screw. This allows the idle speed to be set and when the engine is shut off the throttle closes completely so that it can't diesel or run on.

The other "vacuum canister" is your EGR valve. If it's in the way you can remove it. You will need to block off the port in the manifold or you'll have exhaust blowing right on to the carb.
What a great answer, thank you. I will do without the high idle, the AC dosnt work, but its next on the list.

I figured that was EGR. I removed all the emissions stuff, and vaccumm pump recently, so looks Like I'll have to order a damn block off.
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