kgruber
Final Approach
What exactly will happen if you try to fly with your primer unlocked, or pulled out a little?
Flying with primer unlocked?
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Tom-D
Taxi to Parking
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Tom-D
Depends upon the system.
kgruber
Final Approach
Like on a Cessna 180, or Cherokee 180.
Tom-D
Taxi to Parking
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Tom-D
The Cessna will probably run a little rich, the piper will probably flood out.
The fuel pump on the piper can force fuel thru the open primer, the gravity fed Cessna may not.
Dan Thomas
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Dan Thomas
In a Cessna, the unlocked primer will cause the engine to suck extra fuel. On approach the manifold pressure is low enough to suck enough fuel to load the engine and make it run really rough, and even in cruise it will increase the fuel flow. Since only three of four cylinder on the Lyc are primed, leaning it won't cure the roughness.
We had at least two cases of excessive fuel burn and engine roughness due to the primer being unlocked while students were soloing. One of the first things on the runup checklist is "Primer in and locked."
The primer plunger has a spring-loaded needle that closes off the outlet port in the bottom of the primer cylinder, and that needle isn't doing its job unless the primer is in all the way.
Dan
We had at least two cases of excessive fuel burn and engine roughness due to the primer being unlocked while students were soloing. One of the first things on the runup checklist is "Primer in and locked."
The primer plunger has a spring-loaded needle that closes off the outlet port in the bottom of the primer cylinder, and that needle isn't doing its job unless the primer is in all the way.
Dan
RyanShort1
Final Approach
It has less power, acts sick, and is rough. Had a student do that to me once in a Cherokee 180.
Ryan