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revs up
I have a 1983 F150 flareside that is just about done from a full restoration. I started the engine for the first time today and the RPM's went right up to the max. I had to shut it down quick. The carb is new and supposedly bench tested. the throttle does return to idle. I check the vacuum lines (new) and all seem to be connected. Could it be a leak in the manifold? What should I check next?
Tuned
Joined: Jul 2014
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From: Texas
I had the same thing happen to me the other night. I was working fast because I had to get my truck back up and running for school the next morning. In my hurry, I failed to notice that the Holley carb I installed had a throttle that pulled in the oposite direction as the edlebrock that was on it. The throttle cable when the pedal wasnt depressed was actually holfing it at WOT and when you stepped on it it idled down. Kinda like one of those international loaders. Took me 2 hours of frustration to figure this out.
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From: Denver Metro Area, CO
No.
My guess is you somehow have the carburetor installed incorrectly; without a sufficient supply of gasoline, a huge vacuum leak will keep the engine from running.
Since you seem to have both - lots of gas and lots of air - this is pointing at the carburetor.
My guess is you somehow have the carburetor installed incorrectly; without a sufficient supply of gasoline, a huge vacuum leak will keep the engine from running.
Since you seem to have both - lots of gas and lots of air - this is pointing at the carburetor.
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From: Denver Metro Area, CO
Stated another way - the only way an engine can operate at 5,000+ RPM (WOT) is if it has enough gas + air combined with proper ignition timing to do it. Timing by itself doesn't supply gas & air; too much gas without enough air will flood it; too much air without the gas doesn't produce a burnable mixture.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
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Joined: Mar 2014
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From: AZ
Stated another way - the only way an engine can operate at 5,000+ RPM (WOT) is if it has enough gas + air combined with proper ignition timing to do it. Timing by itself doesn't supply gas & air; too much gas without enough air will flood it; too much air without the gas doesn't produce a burnable mixture.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
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Thread Starter
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Senior User
Joined: Mar 2014
Posts: 354
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From: AZ
Stated another way - the only way an engine can operate at 5,000+ RPM (WOT) is if it has enough gas + air combined with proper ignition timing to do it. Timing by itself doesn't supply gas & air; too much gas without enough air will flood it; too much air without the gas doesn't produce a burnable mixture.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
IOW, the only thing that can cause a WOT condition is just that - a wide-open throttle.
Perhaps the linkage is installed backwards, perhaps the butterfly valves on the bottom of the carb are stuck wide open.
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