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Hi Brian,
Yep! any time the drone of the engine changes - it
immediately gets your attention (or should) {:>). I too have turned on
the cold start when meaning to change controllers - but fortunately
have always immediately recognized the problem.
There are several possibilities about your staging
problem.
1. You may not have the cross over adjustment
(mode 6) tuned properly and when it stages its either too rich or too lean when
running on all four. However, adjustment of you manual mixture control
should indicate which direction (lean or rich) helps the situation.
2. Always possible that a secondary injectors is not
functioning properly - you should be able to check this possibility easily (if
you have the injector disable switches that Tracy shows in his
installation). While on the ground - switch off the primary injectors
(you may get a momentary hiccup if you secondaries are not adjusted properly,
but a quick tweak of the mixture control should keep it running), If it
idles/runs fine on the secondaries then they are likely to be OK.
3. You Fuel Map bin values right after the staging
point could have inappropriate values - Tracy's default is 128 or I guess
it shows up as zero on the EM2 and your adjustments are +- to that zero
reference (128).
You mention the results of enrichen/leaning was
inconclusive - what exactly do you mean? Do you mean you could not tell if
the engine was running rich or lean? The Air/fuel Ratio indicator of
the EM2 is not giving you consistent readings?
Its pretty important as you know to be able to
discern what effect any adjustments are having and mixture is one of the more
important ones.
You'll get it sorted out - some installations simply take
a bit more sorting out than others
Ed
Sent: Wednesday, November 10, 2010 9:51 PM
Subject: [FlyRotary] Re: Improved performance of my new (2009)
intake manifold
Interesting manifold. Are you
still using the VDO fuel pressure sender? I had heard that it might not be
suitable for use with fuel, I am still using mine at present however.
I went up today for a few laps at 3000 over Paine Field. The engine ran
well below the staging point, but started stumbling when above the staging
point. It ran smoothly through the staging transition on the ground, but when in
the air I could not tell by the mixture monitor if it was lean or rich. I tried
leaning it out and richening it up, but results were inconclusive so I stayed
below the staging point for the remainder of the flight. Temps were down around
130 degrees at 4800 RPM and 110 mph, MP was not noted.
I accidently hit the cold start switch while on downwind with two other
planes ahead of me, the tower told me to go around on final, but the plane ahead
turned off onto the taxiway just in time so I told the tower that I would really
like to land, so they cleared me. The engine died as I turned off onto the
taxiway and then I noticed the cold start switch. The first order of business
was making and installing a switch guard for the cold start switch. I'm also
going to pre-load the switch with a rubber band so it stays in the off position
unless I'm pushing it on, and can just pull the rubber band off of it if I need
to shut down a set of injectors and run the remaining injectors on cold
start.(limp home mode for failed injector.)
The fuel self transfering issue was resolved by installing manual valve on
the transfer line between the tanks.
Brian Trubee
-----Original
Message----- From: Dennis Havarlah <clouduster@austin.rr.com> To:
Rotary motors in aircraft <flyrotary@lancaironline.net> Sent: Wed, Nov
10, 2010 12:27 pm Subject: [FlyRotary] Improved performance of my new (2009)
intake manifold
As some of you know I started flying my RV-7A with
a cut - off Renesis intake manifold. In 2009 I installed an new intake
designed to route pressure waves from the closing of rotor #1's
intake into rotor #2 just before rotor #2's intake closed. After
using the new intake for over a year I am still very happy with it's
performance.
I gained about 15 mph TAS at the same altitude and
manifold pressure
My static engine rpm increased 300 to 350
rpm.
My takeoffs are faster and shorter with noticeable
increase in acceleration
My climb rate increased
My oil and water cooling is more critical now
because I make more HP.
But - I must confess I don't believe the manifold
can be reproduced economically. It's just too complicated.
I also believe it should have slightly shorter
intake runners to increase the performance at higher RPM. Decreasing the
intake runner length probably would require complete new geometry of the
system.
I have another concept for designing a
Renesis intake that using a reflected wave from Rotor #1 returning to Rotor
#1 .
I believe it would be much easier to build and
small enough to fit into the James rotorary cowl but because my intake works
well I am not moving ahead with completing the design and building
it.
Dennis Haverlah
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