> -----Original Message-----
> From: Al Gietzen [SMTP:ALVentures@cox.net]
> Sent: Sunday, October 03, 2004 1:39 AM
> To: Rotary motors in aircraft
> Subject: [FlyRotary] Re: MAP pulses (20B)
>
>  << File: ATT00007.htm >> What surprised me was that with the engine
running at 2000, the pointer was
> swinging very rapidly over a range of over a pretty wide range; from about
> 27 to 37 psi.  It is an undamped bourdon-tube gauge, responding to a lot
of
> pulsing.  I had no pulse filtering between the manifold and the fuel
> pressure regulator.
>
> Was the engine running smoothly at 2000?  Did all the improvements you
made
> actually allow you to run a smooth idle down around 1000 or so?
>
> Yes it was; so I can't say the pulsing in the fuel pressure was
interfering
> with the operation at lower rpm; it was, at the least, indicative of
uneven
> MAP and likely very hard on the FP regulator.  I haven't run lower than
> about 1500 yet since that is where the idle stop is set; and I am pursuing
> other issues. But it does now run smoothly at that speed - secondary
> injectors only.  The other issues are that the "staging" is not working;
it
> does not run completely smoothly with both sets on; less smooth on primary
> only; and very smooth with secondary only (primary turned off).  If you
can
> figure those things out for me, you win the cigar.  Still waiting on a new
> chip for the EM2, but the next time I run I'll slow it down further.
>
> Al
>
Al, here's one possibility that you might considered

1.  A problem in the EC2 sensing manifold pressure being sensed.  In other
words, it is "staged" all the time which if the case would of course provide
too much fuel at the lower rpms with all 4 injectors on.  Switching off the
primaries then "destages" the circuit and you get a smooth idle at lower
rpm.  Could be the MAP sensor or your manifold pressure sensing hose.

2.  Have you tried the "B" controller? same results or different?  If it
were the A controller MAP sensor or its sensing hosing then switching to
"B:" should cause it to run smoother.

3. Primary injectors could be leaking - but, if it were truly leaking then I
wouldn't think turning off the primary would stop the leak.

The fact that it is running well on the secondaries but runs worst when both
are on


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