Thanks Mark,
Fuel Pressure is remaining constant.  
Joe

---- Original message ----
>Date: Mon, 20 Jul 2009 09:20:19 -0500
>From: Mark Steitle <msteitle@gmail.com>  
>Subject: [FlyRotary] Re: Alternator Filter  
>To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
>
>   Joe,
>    
>   The first thing to come to mind is that with the
>   alternator on-line you have a higher bus voltage
>   which would cause the electric fuel pump to run
>   faster and produce more pressure.  But the fuel
>   pressure regulator should take care of the higher
>   pressure, assuming it is working properly.  If the
>   fuel pressure does rise when you bring the
>   alternator on-line, then that could cause the engine
>   to go rich and run rough.  Just a thought...
>    
>   Mark S.
>
>   On Mon, Jul 20, 2009 at 8:38 AM,
>   <jewen@comporium.net> wrote:
>
>     Tuning is coming along pretty well on my newly
>     running 20B.  I have run into a bit of a snag.
>      Until last week I was running only on battery
>     power, then I brought my alternator on line.
>      When the alternator is turned on, the engine
>     starts to stumble and run rough.  As soon as the
>     alternator is turned off it starts to run smoothly
>     again.  Any suggestions for alternator filtering?
>
>     Thanks,
>     Joe
>
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