Second flight.. 15 minutes. Still chasing fuel mixture problems.


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Comment by Ken Pavlou on November 11, 2014 at 11:57am
Dan, it's your plane and you can do whatever you wish, but I strongly suggest using the Marvell Schebler carb WW recommends. I have one in my 601 and after 168 hours have had zero issues with it. It simply works. You can get one ready to instal from Russ Romey at D&G. Good luck.
Comment by Dan Dempsey on November 10, 2014 at 9:31pm

As I climb out the engine runs leaner and leaner.  It may be related to speed.  Ram air can be one cause of lean mixture condition even at full rich mixture setting.  It doesn't improve until I start my decent.  I've got a couple things to try.  I'm going to try blocking off the source of the ram air, and just use the air under the cowl.  I had also made a change to reduce the amount of travel available on my mixture control in the linkage.  I'm going to add it back in and see if I can't feed it enough fuel on climb out.   If neither of those fix it, I'm going give up on the SU carburetor and get an MA3SPA Marvel Schebler like William Wynne recommends.

Comment by Jesse Hartman on November 9, 2014 at 10:07pm

So what is going on? unable to hold an certain ratio? Shooting for 12.7  

Comment by Dan Dempsey on November 9, 2014 at 7:57pm

Jesse, I have both a wide band 02 sensor / fuel ratio gauge and EGT.

Comment by Jesse Hartman on November 9, 2014 at 6:04pm
Whats the problem? Do you have an wideband O2 sensor?

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