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Adding a fuel flow guage to a c35

I have a c35 that was repowered many years ago with an e225. I would like to add a fuel flow guage. I was wondering what is involved given the pressure carb. Would a manifold / fuel flow guage from a newer plane be an easy install? Thanks

Model: Bonanza C35
Aircraft Serial Number: N1875D
Posted 12/28/2021 - 4 months ago
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With the pressure carb, you will not be able to install a direct reading unit. A digital unit with two transducers and a fuel-flow differential module will be needed. (One transducer each for fuel in to carb and return fuel to airframe, FFDM to do the math for the panel unit.

On J P Instruments website: https://www.jpinstruments.com/shop/fuel-scan-450/
In the options list on the right when you scroll down, the FS450D has dual transducers for the pressure carb. (Other manufacturers have similar)

Mike
ABS Technical Advisor

Posted 12/28/2021 - 4 months ago
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Thanks

Posted 12/28/2021 - 4 months ago
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Installing a fuel flow system will make it much easier to run LOP with the PS 5C carburetor. Although I have an engine monitor with LOP capability I find the fuel flow system helps a great deal in actually doing LOP.

The PS 5C has uneven fuel distribution with WOT (wide open throttle) and throttle position can make a difference in getting all of the cylinders LOP. After takeoff and setting the 1/2 inch MP reduction from WOT and climbing to altitude (example 9500 MSL) I simply bring the fuel flow back to 8.2 to 9.0 GPH which will usually bring either all cylinders LOP or maybe the two rear cylinders (#1/2) are not LOP. By slightly opening the throttle a turn or two the two rear cylinders will join the other four in being LOP. That throttle movement is not enough to change the MP reading but enough to change the mixture distribution. Exact throttle position on the PS 5C determines the fuel distribution to the 6 cylinders.

After experience is gained with the fuel flow system and knowing what the LOP fuel flow will be at various altitudes and setting the FF to that flow rate then the LOP fuel distribution to the cylinders can be trimmed with that very small amount of throttle movement. With the throttle wide open the two rear cylinders will be leaner than the other cylinders. Therefore, if with the throttle reduced to the 1/2 inch MP (rough setting to even the fuel distribution) below WOT for the climb, then the throttle can be opened ever so slightly to bring the two rear cylinders LOP if they do not go LOP when the other four cylinders do. Not as scientific as the balanced GAMI fuel injector system but a little experience using the fuel flow system with the PS 5C carburetor it produces a similar result.

All of the above is what I have discovered along those lines.

Regards, Lew Gage

Posted 12/30/2021 - 4 months ago
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Clay - We are upgrading our G35 Bonanza with an E225 engine to a JPI 930 engine monitor. We have a JPI-450 that is being replaced. It will fit your airplane. If you are interested email me at Stinson97502@gmail.com and we'll get together on it.
Regards
Rodney Wren

Posted 1/4/2022 - 4 months ago
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Thanks all. Looking at the engine monitors…JPI and EI

Posted 1/23/2022 - 3 months ago
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Adding a fuel flow guage to a c35