Mailing List flyrotary@lancaironline.net Message #11967
From: Steve Brooks <prvt_pilot@yahoo.com>
Subject: RE: [FlyRotary] Re: #$!%@$ temperatures still high
Date: Wed, 6 Oct 2004 07:35:16 -0400
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>
Dave,
I don't have any other electrical issues other than the coil test issue with
the controller.  I also do not have any relays in the field circuit, just a
switch on one side of the master switch.

I will double check it though.  Thanks.

Steve

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On
Behalf Of DaveLeonard
Sent: Wednesday, October 06, 2004 12:51 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: #$!%@$ temperatures still high


To make a long story long again, here is a re-broadcast of my voltage fix:
----------------
Like many, I have been plagued by a rough idle.  Today it is fixed.

The little electrical gremlins that pop up were starting to drive me crazy.
One landing light sometimes comes on when it is turned off, and last night I
discovered that the nav lights don't stay on.  After about 15 min. of
running the engine on the ground the micro relay in my controlvision EXP
BUSS II must get overheated because the nav lights went out.  Turning them
off for a few seconds (resetting the micro relay) would allow them to come
on briefly before going out again.

Then the strobe did the same thing.  Now that I think back, it turns out
that every time I fly the strobes have been turning themselves off shortly
after starting the flight but I just never took notice. (while the landing
light turns itself on).  It seems that the circuits on the EXP Buss can not
really handle their rated power very well.  Those were supposed to be 7 amp
circuits which is a little more than the draw, but the circuit was only able
to last for about 10 min.

Then it hit me - The alternator is using an OV protected 5Amp circuit from
the same board… and the lights really seem to sort of flicker (have tried
about 10 different useless solutions for that one).

Anyway, the excitation current for the alternator must be right at about 5
amps.  Turns out the micro relay has been tripping, then resetting itself
2-3 times /sec. Turning the alternator on and off with it.  The poor voltage
regulator must have been working overtime as my buss voltage read a steady
14.2V.  The fluctuations were too fast to register on the voltmeter.  The
voltage must have been going from battery voltage up to about 16+ volts to
maintain the average of 14V read by the meter.  As you can guess,
electronics don’t like that kind of thing – but most things worked
surprisingly well.

I bypassed the stupid circuit board and connected the alternator field
directly to the alt output.  Wow what a difference.  The EC2 and fuel pumps
were probably the most affected.  All of a sudden I can get idle out of the
ultra rich and put the mixture right.  Idle is MUCH better.  I even had to
reset the idle stop so I could idle lower.  Down to 1000 RPM or less now and
it sounds great.  Oh, the lights stopped flickering and the radios sound
better too.  Go figure.

Dave Leonard


David,
What was the voltage issue ?

Steve

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On
Behalf Of DaveLeonard
Sent: Tuesday, October 05, 2004 8:05 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: #$!%@$ temperatures still high


Steve,  sorry to hear that your temps are so high.  One thing I
notice about
your description that is different from what I experience is the
speed with
which your temps seem to change.  My system seems to have
significantly more
inertia.

It is possible to me to overheat the coolant, but I really have to be
climbing hard or running a lot of boost.  On the first take off
of the day I
have several minutes of steep climbing (6-7000') before I need to
level out
some and pick up speed.  If the engine is already hot I have to be careful
from the start.  Likewise when coming down.  If I do get my coolant up to
220, it takes a full five minutes of low power descent to get it back into
the low-normal range.

I wonder what is different between our systems - volume of coolant?
Whatever it is, this may a clue for you.

I would definitely fix the mixture.  I had that problem as well and it was
greatly improved with detailed and repeated narrow width (mode 2)
programming.  Then I found my voltage problem and fixed it all.

JMHO,
Dave Leonard



> I flew the Cozy this after noon, and was very disappointed in the
> temperatures.  The OAT was 81, and the coolant read 225 on the
temperature
> gauge, and the oil climbed slowly to 207 peak.  The coolant did
come down
> about 10 degrees when I throttled back at pattern altitude, but
> leveled off
> there.
>
> When I throttled back on approach the coolant was about 180 and
oil 190 on
> touchdown.
>
> It appears to me that I don't have enough sq in of inlet area.  I
> do have a
> P51 style scoop that I can bolt on, and try, but I don't have
> allot of faith
> that it will solve the problem.  Tomorrow, it is suppose to be
> cooler, about
> 55 or so in the A.M., so maybe I'll try the other scoop with the cool
> temperatures just to see what happens.  If the temperatures are
low, I may
> fly for an hour or more, just to test some other systems.
>
> My next plan is to cut off the 2 12 sq in armpit scoops and
> enlarge them to
> 25 sq in.  I'll then remove the oil cooler from the main scoop,
which will
> give the A/C evaporator cores about 22 sq in of additional inlet
> area.  I'll
> feed the oil cooler from one of the armpit scoops.  The other
armpit scoop
> feeds the intercooler and engine inlet air.
> That is, unless someone has a better idea.
>
> I have a couple of other nagging issues:
>
> 1) I seem to be running rich.  I turned the fuel pressure down
> some (30 PSI
> on my gauge (don't know if it's accurate)). That helped, but
running both
> fuel pumps makes the engine run very rich at full power.
Turning off one
> pump increases power and smoothness.  At an idle, 1000-2000
RMS, if I shut
> off the main fuel pump, the engine smoothes out, and gain a little rpm,
> before running out of fuel.
>
> 2) For whatever reason the "coil test" has stopped working.  I
used to be
> able to go to the "B" controller, and do the coil test to check
> the leading
> or trailing coils.  That doesn't work, and if I turn it to off
(I'm using
> the ignition switch), it keeps on running.  Used to kill the
> engine before.
> I'm not sure what this is, and haven't really done any testing yet.
>
> Steve Brooks (praying for cold weather)
>
>
>
>
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