Tracy,

I think you’re right on here.  One other mandatory change coming from the Eggenfellner engine-outs was to move the fuel pumps from the firewall to the cabin floor.  That alone might have been enough to “fix” the problem. 

 

Mark (trying to figure out where this vertical bar came from) 

 

 

That's the problem with this kind of data.  I'm sure the Eggenfellner people were telling the truth about what they saw but you can't then generalize and make their solution a 'carved-in-stone' rule.  I have no details on their system but I suspect there was a deficiency in their fuel system which their bleeder fix covered up or compensated for.    Like Al, I've never seen this problem on my plane or engine test stand.

 

Tracy  (trying to figure out why I can't change the text color when I reply to Al's posts)