X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-lpp01m020-f180.google.com ([209.85.217.180] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTPS id 5384782 for flyrotary@lancaironline.net; Mon, 06 Feb 2012 11:26:22 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.217.180; envelope-from=rwstracy@gmail.com Received: by lboi8 with SMTP id i8so1037286lbo.25 for ; Mon, 06 Feb 2012 08:25:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=AtfU0bzdgtX4ISlbSdSLf+rt7PiIizjPYAUA7he9ybw=; b=eybohy6S33hAyKa3I157mtt6qYGp/CPu47N9KEBfgEu5A5DYg4j5pNP/EEtYAbRBSV CNanQ9twqV8V537Nk9CuvN7sUT2wOBxr3tn3M22Tr8++ozDi1TffpAH0vJG/Uv1S7rR6 cmQkDlS+na4RG2atvQGL4ATAJOkteI8QYHcC4= MIME-Version: 1.0 Received: by 10.112.25.74 with SMTP id a10mr5005540lbg.58.1328545546802; Mon, 06 Feb 2012 08:25:46 -0800 (PST) Received: by 10.112.75.74 with HTTP; Mon, 6 Feb 2012 08:25:46 -0800 (PST) In-Reply-To: References: Date: Mon, 6 Feb 2012 11:25:46 -0500 Message-ID: Subject: Re: [FlyRotary] Re: Upper end tuning From: Tracy To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=bcaec55556ba62960804b84e1db9 --bcaec55556ba62960804b84e1db9 Content-Type: text/plain; charset=ISO-8859-1 Hmmm.... Hard RPM limit... Using the 13 BREW... Have we discussed the EC2 3rd gen crank sensor compatibility issue? Tracy On Mon, Feb 6, 2012 at 11:15 AM, wrote: > This was at any altitude- I'll take off at sea level and on climb out if > the rpms get to 6100, the engine stumbles as if it were suddenly way too > lean. So, what I'm saying is that this can happen at any altitude. It seems > to be more of a RPM issue than of manifold pressure. > > As far as the EGT goes, it may be an instrumentation error. > > I've tried to richen up the mixture and then go up past 6100 rpm, but I > still get the power drop. > > And yes, I have the EM2 set at the factory setting for engine max power, > so all I'm seeing is just an arbitrary number. > > So, I'm going to change spark plugs and do some more flying. The weather > is nice out here for the next few days so I have some opportunity to fully > explore what's going on. > > Brian Trubee > > > -----Original Message----- > From: Tracy > To: Rotary motors in aircraft > Sent: Mon, Feb 6, 2012 6:00 am > Subject: [FlyRotary] Re: Upper end tuning > > Can't make an educated guess from the data given but here's a few > questions & comments. > > Can you clarify what you mean by "precipitous power drop"? Does the power > go down at higher MP? (6100 at 22.6" aint bad on a FP prop. What was the > airspeed & altitude? EVERYTHING MATTERS!) > > Is the EGT imbalance only at high power? Are you sure it's not > instrumentation error? > > As Ed asked, what was the result of varying the mixture control at high > power? > > You say that engine is silky smooth below 6100. Does that imply it is > rough above 6100? > > The % power readout of the EM2 is meaningless if the fuel flow function > isn't calibrated and you haven't plugged in a realistic value for your > engine's max power. > > Tracy > > > On Sun, Feb 5, 2012 at 10:01 PM, wrote: > >> I've got just over 20 hours on my plane today, all of the lower- end bugs >> have been worked out. Right now I'm having power drop off precipitously >> right at 6100 rpm- 22.6 inches of MP and around 70% power according to the >> EM2. This is around 130-140 mph IAS. The fuel injection Map shows a smooth >> graph at that point. I thought that there might be a timing issue so I >> tried advancing the timing about 2 degrees but that did not change a thing >> so I set the timing back where it was previously. I am seeing about a 180 f >> difference on the two rotors- I went to mode four to try to balance out the >> egts, but I could only effect about a 20 degree change. Rotor 2 >> consistently shows somewhere above 1800 F, which I tend to question. I'll >> re-check my calibration. I have had the injectors cleaned and tested so >> unless one of them got clogged, that should not be an issue. Still, I >> should pull them and have them re-checked. I may have an issue with the EGT >> probes themselves. >> >> Down below 6100 rpm the engine is smooth as silk, but obviously there is >> an issue above that . >> >> >> Brian Trubee >> RV-4 13 BREW >> >> > > --bcaec55556ba62960804b84e1db9 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hmmm....=A0=A0 Hard RPM limit... =A0 Using the 13 BREW... =A0 Have we discu= ssed the EC2 3rd gen crank sensor compatibility issue?

Tracy
On Mon, Feb 6, 2012 at 11:15 AM, <bktrub@aol.com> wr= ote:
This was at any altitude- I'll take off at sea level=A0 and on cli= mb out if the rpms get to 6100, the engine stumbles as if it were suddenly = way too lean. So, what I'm saying is that this can happen at any altitu= de. It seems to be more of a RPM issue than of manifold pressure.
=A0
As far as the EGT goes, it may be an instrumentation error.
=A0
I've tried to richen up the mixture and then go up past 6100 rpm, = but I still get the power drop.
=A0
And yes, I have the EM2 set at the factory setting for engine max powe= r, so all I'm seeing is just an arbitrary number.
=A0
So, I'm going to change spark plugs and do some more flying. The w= eather is nice out here for the next few days so I have some opportunity to= fully explore what's going on.
=A0
Brian Trubee


-----Original Message-----
From: Tracy <rws= tracy@gmail.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, Feb 6, 2012 6:00 am
Subject: [FlyRotary] Re: Upper end tuning

Can't make an educated guess from the data= given but here's a few questions & comments.

Can you clarify what you mean by "precipitous power drop"?=A0 Doe= s the power go down at higher MP?=A0 (6100 at 22.6" aint bad on a FP p= rop.=A0 What was the airspeed & altitude?=A0 EVERYTHING MATTERS!)

Is the EGT imbalance only at high power?=A0 Are you sure it's not instr= umentation error?

As Ed asked, what was the result of varying the mixture control at high pow= er?=A0

You say that engine is silky smooth below 6100.=A0 Does that imply it is ro= ugh above 6100?

The % power readout of the EM2 is meaningless if the fuel flow function isn= 't calibrated and you haven't plugged in a realistic value for your= engine's max power.

Tracy


On Sun, Feb 5, 2012 at 1= 0:01 PM, <bktrub@aol.com> wrote:
I've got just over 20 hours on my plane today, all of the lower- e= nd bugs have been worked out. Right now I'm having power drop off preci= pitously right at 6100 rpm- 22.6 inches of MP and around 70% power accordin= g to the EM2. This is around 130-140 mph IAS. The fuel injection Map shows = a smooth graph at that point. I thought that there might be a timing issue = so I tried advancing the timing about 2 degrees but that did not change a t= hing so I set the timing back where it was previously. I am seeing about a = 180 f difference on the two rotors- I went to mode four to try to balance o= ut the egts, but I could only effect about a 20 degree change. Rotor 2 cons= istently shows somewhere above 1800 F, which I tend to question. I'll r= e-check my calibration. =A0=A0I have had the injectors cleaned and tested s= o unless one of them got clogged, that should not be an issue. Still, I sho= uld pull them and have them re-checked. I may have an issue with the EGT pr= obes themselves.
=A0
=A0Down below 6100 rpm the engine is smooth as silk, but obviously the= re is an issue above that .
=A0
=A0
Brian Trubee
RV-4=A0 13 BREW
=A0


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