X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 18 Apr 2012 15:34:42 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-scoter.atl.sa.earthlink.net ([209.86.89.67] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTP id 5487499 for lml@lancaironline.net; Wed, 18 Apr 2012 14:55:44 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.67; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=DjK9KS4HufMKkhHIW9PUPUzJ1WcDDqFMGDqb9vLTNJyYYw2wrnmVPBpNPGCWGWRF; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [64.222.109.232] (helo=[192.168.1.24]) by elasmtp-scoter.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1SKa1z-0005qx-TI for lml@lancaironline.net; Wed, 18 Apr 2012 14:55:08 -0400 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-1147--14177847 Subject: Re: [LML] Re: TSIO 550 Hot #2 cylinder X-Original-Date: Wed, 18 Apr 2012 14:55:07 -0400 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: X-Mailer: Apple Mail (2.1084) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940d4ed604c7a936031e3eb4bbc7132ec4e350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 64.222.109.232 --Apple-Mail-1147--14177847 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Lynn, Is it a sure thing that you would not get into the fatally rich scenario = doing this? Colyn On Apr 18, 2012, at 11:00 AM, Lynn Farnsworth wrote: Ralf, =20 If you think the high CHT is being caused by lean mixture at 32=94 MP = with the mixture full rich, try this; turn on the high boost fuel pump. = This will normally increase the fuel flow by 4 to 5 GPH. If this keeps = your #4 CHT down your have validated your suspicion. =20 If you have GAMI injectors you can try replacing the current injector = with one that allows more fuel to that cylinder. =20 =20 Turning on the high boost for a temporary condition it an inexpensive = remedy.=20 =20 Just a thought. =20 Lynn =20 =20 From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = Craig Berland Sent: Tuesday, April 17, 2012 4:55 PM To: lml@lancaironline.net Subject: [LML] Re: TSIO 550 Hot #2 cylinder =20 Ralf, =20 I had the exact same situation on my IV-P. At full power (2700 rpm; 38 = inHg; 43 gph) my engine ran nice and cool. At all LOP conditions, my = engine ran nice and cool. I define nice and cool as below 380 degF. At = full rich and 65% to 95% power, my engine ran hot because it was =93too = lean=94 at full rich. I went out and fuel mapped my engine from 2200 = rpm to 2700 rpm and 22 inHg to 38 inHg. I didn=92t fill in all the boxes = but most of them. I did not run high MAP at the lower rpm=92s. When I = plotted out the data, using my best estimate for power at each setting, = my suspicion was confirmed. The fuel system was running about 3-4 gph = lean at the reduced power settings when full rich. The solution was a = bit radical. I worked with Dave Dewell at Great Planes Fuel Metering = and he modified my fuel cam to fix the problem. In the process, we = correlated my flight data to his test stand data. This process is not = for the weak of heart but my engine now runs cool at all power settings. =20 Dave Dewell Great Planes Fuel Metering ddgpfm@tulsacoxmail.com 918 695 4356 =20 Craig Berland N7VG =20 =20 Dear subscribers, =20 Since we are talking about hot cylinders I got one question that bothers = me: I have a plenum and I tried to do a very anal job in sealing all the = leaks around the engine =96 I followed Fred Moreno=92s instructions = there. I have different temperature patterns amongst the cylinders for = different situations. LOP cruise: #2 is the warmest and is usually between 330 and 370 = depending on altitude, humidity, fuel flow etc. =96 always very cool no = issue at all Climb 32=94 MAP, 2500 1/min, full rich : cylinder 4 wants to get warm = and I keep the airspeed around 180 in order to stay below 400F. This is = the situation I am not really happy about =96 if I don=92t pay attention = on a warm day the #4 will get above 400F Climb 2500 1/min, full rich, full throttle: even temperature profile = amongst the cylinders. Engine runs generally cooler and airplane climbs = faster. =20 I tried to watch the EGTs and see if #4 is running lean but I could not = tell a difference in the EGT. #4 has the dip stick pipe and more hoses = that could influence airflow. =20 Any idea why #4 is warmer at 32=94? =20 Thanks for your help =20 Ralf --Apple-Mail-1147--14177847 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Lynn,

Is it a sure thing that = you would not get into the fatally rich scenario doing = this?

Colyn

On Apr 18, = 2012, at 11:00 AM, Lynn Farnsworth wrote:

If you = think the high CHT is being caused by lean mixture at 32=94 MP with the = mixture full rich, try this; turn on the high boost fuel pump. This will = normally increase the fuel flow by 4 to 5 GPH. If this keeps your #4 CHT = down your have validated your suspicion.
 
If you have GAMI injectors you can try replacing = the current injector with one that allows more fuel to that cylinder. =   
Just a = thought.
 
From: Lancair Mailing List = [mailto:lml@lancaironline.net] On Behalf Of Craig = Berland
Sent: Tuesday, April 17, 2012 = 4:55 PM
To: lml@lancaironline.net
Subj= ect: [LML] Re: = TSIO 550 Hot #2 cylinder
Ralf,
 
I had the exact same situation on my IV-P.  At full = power (2700 rpm; 38 inHg; 43 gph) my engine ran nice and cool.  At = all LOP conditions, my engine ran nice and cool.  I define nice and = cool as below 380 degF.  At full rich and 65% to 95% power, my = engine ran hot because it was =93too lean=94 at full rich.  I went = out and fuel mapped my engine from 2200 rpm to 2700 rpm and 22 inHg to = 38 inHg. I didn=92t fill in all the boxes but most of them.  I did = not run high MAP at the lower rpm=92s.  When I plotted out the = data, using my best estimate for power at each setting, my suspicion was = confirmed.  The fuel system was running about 3-4 gph lean at the = reduced power settings when full rich.  The solution was a bit = radical.  I worked with Dave Dewell at Great Planes Fuel Metering = and he modified my fuel cam to fix the problem.  In the process, we = correlated my flight data to his test stand data.  This process is = not for the weak of heart but my engine now runs cool at all power = settings.
 
Dave Dewell
Great Planes Fuel = Metering