Isham Posted June 6, 2020 Report Share Posted June 6, 2020 With the engine warmed and choke off, when I put slight pressure forward (more choke off) the engine RPM increases about 100-150. I think the choke must be on a tiny bit all of the time. How do I adjust this? Probably cable needs more tension in the off position. Quote Link to comment Share on other sites More sharing options...
Tom Baker Posted June 6, 2020 Report Share Posted June 6, 2020 More than likely you are flexing the area where the throttle mounts. Sometimes I have seen a RPM decrease when applying brakes. You can check the choke easy enough by removing the top cowling and looking at the choke valve on the sides of the carbs. There are 2 little post on each carb that are the stops for the choke. When the choke is full on it should be against one post, and when it is full off against the other. Quote Link to comment Share on other sites More sharing options...
Isham Posted June 6, 2020 Author Report Share Posted June 6, 2020 Thanks Tom. I will check it this morning. Had not thought about the flexing possibility. Quote Link to comment Share on other sites More sharing options...
Isham Posted June 6, 2020 Author Report Share Posted June 6, 2020 The chokes are fine. They are on the stops so I was flexing the throttle when pushing harder on the choke control. Thanks Tom for the input. Quote Link to comment Share on other sites More sharing options...
Skunkworks85 Posted June 6, 2020 Report Share Posted June 6, 2020 On 6/6/2020 at 9:41 AM, Isham said: The chokes are fine. They are on the stops so I was flexing the throttle when pushing harder on the choke control. Thanks Tom for the input. this happens on my SW Quote Link to comment Share on other sites More sharing options...
MEH Posted June 8, 2020 Report Share Posted June 8, 2020 I had the RPM rise issue when pushing the choke lever forward and thought it was due to flexing as the cable didn't seem too tight at the carbs. I didn't find the RPM rise after a flight, but only after start up on cold days. When I added extra slack, the RPM rise went away. My theory is that there is a small thermal shrinkage in the cable when it is cold which takes up the slack that is there when adjusted in the warm hangar. An internet calculator computes a 0.017" decrease in a 36" stainless cable with a 50 degree temperature drop. Might be enough???? Adding some more slack in the choke cable only takes 5 minutes. Then you will know for sure. Quote Link to comment Share on other sites More sharing options...
207WF Posted September 20, 2020 Report Share Posted September 20, 2020 I get a small rpm increase in my SW when I use the brakes. WF Quote Link to comment Share on other sites More sharing options...
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