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- Deep Thoughts
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Re: Engine RPM's run away at start-up.
You seem to be suggesting that the igniter suddenly took a dump at exactly the same time you were screwing around with the carbs. Or maybe "something more problematic". I think it's a lot more likely that you just hooked something up wrong or misinterpreted the idle adjust screw. No offense: this is exactly what I would be telling myself.
Yes, CV carbs are finicky; but I think most of that mystery revolves around the need for "clean" laminar flow into the carbs so that the whole Bernoulli thing happens right in the top of the carbs. This is fundamental to how these "constant depression" carbs work.
I suggest using a dentist's mirror to look into the carbs -- are the slides all down? I bet one is hung, for any number of reasons. Maybe try to see beyond them to verify that the butterfly valves are closed as you expect.
Did you replace the carb-sync vacuum port plugs?
Yes, CV carbs are finicky; but I think most of that mystery revolves around the need for "clean" laminar flow into the carbs so that the whole Bernoulli thing happens right in the top of the carbs. This is fundamental to how these "constant depression" carbs work.
I suggest using a dentist's mirror to look into the carbs -- are the slides all down? I bet one is hung, for any number of reasons. Maybe try to see beyond them to verify that the butterfly valves are closed as you expect.
Did you replace the carb-sync vacuum port plugs?
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Nails
Nails
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Re: Engine RPM's run away at start-up.
have you checked the enrichener circuit ie choke cable moving the slide back and forth freely? if stuck on at startup will race to 4500 rpm easy
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- cushman eagle (Sat Aug 20, 2022 1:00 am)
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Re: Engine RPM's run away at start-up.
I am a bit confused here, you started it up and it idled fine. But you wrote that you backed the idle screw all the way closed. ??
( " Today I installed the throttle cables leaving them with neutral tension in the adjusters. (linkage completely closed)
I backed the idle knob all the way to closed " )
Why did you even touch the idle screw at that time if it idled OK when you first started it ? Go back and turn it CCW .
( " Today I installed the throttle cables leaving them with neutral tension in the adjusters. (linkage completely closed)
I backed the idle knob all the way to closed " )
Why did you even touch the idle screw at that time if it idled OK when you first started it ? Go back and turn it CCW .
"Its not bad if you don't know something, but when you don't know you don't know; That's when your in trouble". Joe Place 1912-2008 (my grandfather)
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Re: Engine RPM's run away at start-up.
I am glad you resolved it so quickDeep Thoughts wrote: ↑Fri Aug 19, 2022 1:03 am EDIT: This was a non-issue and is resolved. Thank you to those who offered insight.
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It would be nice if all issues were resolved so easy
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'99 Voyager VXII,'58 Cushman Eagle