C140 Installation of Carb w/ Mixture Control

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harejac
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C140 Installation of Carb w/ Mixture Control

Post by harejac »

I'm a new C140 owner (1st airplane). My plane has a C-85-12 the Stromberg carburetor without any mixture control. Moving to a higher elevation area next year and will need a carburetor with mixture control for normal operations. Looking for suggestions on which carburetor is best to install with the C-85. Any information is greatly appreciated!
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Re: C140 Installation of Carb w/ Mixture Control

Post by tonycondon »

mixture control can be added to your stromberg. it is very likely that all the guts are there and the control is just wired full rich. if the guts are not there, they can be purchased from Fresno and installed by a competent mechanic or overhaul facility.

mine came without the guts, and eventually required overhaul. at overhaul i had the shop add the mixture control, and i used a mixture knob from McFarlane. Works nice.
N2395N
harejac
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Re: C140 Installation of Carb w/ Mixture Control

Post by harejac »

Ran that by my mechanic and he told me that all my guts are there! Said he could install the mixture control no problem. Would you happen to know the exact parts you used?
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6643
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Re: C140 Installation of Carb w/ Mixture Control

Post by 6643 »

Where are you moving to? The Stromberg mixture control is not necessary until you get to about 5000 feet. Below that the carb does a pretty good job without it.
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Re: C140 Installation of Carb w/ Mixture Control

Post by harejac »

6643 wrote: Mon Oct 28, 2024 5:17 pm Where are you moving to? The Stromberg mixture control is not necessary until you get to about 5000 feet. Below that the carb does a pretty good job without it.
I'm moving to El Paso, TX. Field elevation is 3,500ft at ISA.
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Re: C140 Installation of Carb w/ Mixture Control

Post by 6183 »

If you haven’t already done so take a look at this Neal Wright article on the Stromberg carburetor mixture control useage.
viewtopic.php?p=608#p608
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Re: C140 Installation of Carb w/ Mixture Control

Post by 6643 »

At 3500 feet I doubt you'll have a noticeable difference in performance between a Stromberg without a mixture control, one with, and a Marvel Schebler with mixture control. The farther you get above 5000 feet, you'll notice a gradual decrease in performance without the mixture control. The other two options operate differently but have similar performance.

Read the article by Neal Wright. It'll help set the proper expectations from the Stromberg.
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