Need some carb help
#1
Need some carb help
I can not seem to get it to idle correctly...have a 79 with 302....after inspection it looks to me like the throttle solenoid is either not working or not set up correctly. With the throttle at idle I thought the solenoid would be in contact wioth the throttle...there is about half an inch of space even with the solenoid plunger fully extended.
What am I missing?
What am I missing?
#2
#3
This solenoid is called an "idle stop solenoid." This solenoid is powered from hot-in-RUN, meaning it's powered (and engaged) the entire time the engine is running. When the engine is running, the idle speed is maintained by the solenoid - meaning the throttle tab should rest on the solenoid plunger. When the engine is shut off, the solenoid retracts, and the throttle plates are allowed to close (almost) completely. This was done to prevent dieseling on later model smog motors that tended to require a higher idle speed, yet ran at hotter combustion chamber temperatures (which is the perfect recipe for dieseling).
On this kind of setup, the idle speed is adjusted by a long screw that moves the entire idle stop solenoid bracket toward and away from the throttle stop. With the engine OFF and the solenoid retracted, the throttle plates should be able to nearly close. You don't want them to close completely, otherwise they will bind in the throttle bores. Instead, adjust the standard curb idle screw (on the carburetor base, driver side) so that with the solenoid retracted, the throttle plates are open ever-so-slightly.
#4
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