ORIGINAL: Pa-18cub150</p>
I have an OS 61 FSR with a 7D carb no insert, and no pump Runs great but I am only getting</p>
adopt 8 minutes flight time with a 16 oz tank. (Full throttle) Is this about right?
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I would imagine that if your running the engine without the insert that you would have to increase the amount of fuel delivered to the engine due to the increase in airflow to keep it from running lean. According to the 7D - 7DV manual OS suggests that you use some type of pump with the small diameter insert removed.
I suspect that the engine is not running efficiently as it should, soI concur with flywilly thatit's possible that your just wasting fuel, Measure the diameter of the carb rotor. It might have the 7DV carb rotor installed in a 7D carb body. If it's the DV rotor it's diameter is aready 8.5mm and you won't need he inserts anyway. Another issue is the type of fuel you're using. If your using 20% nitro you'll useway more fuel than say 5 or 10%. Post a pic of the carb.</p>
ORIGINAL: Pa-18cub150
What is needed to make the 9b carb insert work?
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You would need to grind down the gap where the insert comes together inside the rotor andyou would need to make sure that the two holes allow the mixture control valve to passthrough.</p>
I have not tried this but you could possibly use one of the carb inserts OS has for the carengines. In this case it inserts into the top of the carb. Would be way simpler if they fit.
Bryan</p>