X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 26 May 2012 15:34:38 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-mealy.atl.sa.earthlink.net ([209.86.89.69] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTP id 5561892 for lml@lancaironline.net; Sat, 26 May 2012 14:20:50 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.69; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=uF34OGrM0OMD0EIy43kLTd4U2S6VWr0Zy42+rsWN/aZIL4rEuBONasCw9A74oqah; 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 [70.20.47.48] (helo=[192.168.1.24]) by elasmtp-mealy.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1SYLay-0000ZE-7p for lml@lancaironline.net; Sat, 26 May 2012 14:20:08 -0400 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-88--1028044836 Subject: Re: [LML] boost pump for engine cooling 4P X-Original-Date: Sat, 26 May 2012 14:20:07 -0400 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: <3FF9C217-A0CE-4E37-9AEC-B1E80304D9B6@earthlink.net> X-Mailer: Apple Mail (2.1084) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940c733b39a75e5784aa4c10345f655ec40350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.20.47.48 --Apple-Mail-88--1028044836 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Ralf, I actually have my fuel set at 45gph @2750/38. That is the extreme = high end of the range. ..so one angle might be to add another 1.5 gph or so to your fuel flow. = =20 However, from everything else you are saying, it seems like you would = want to find out what is going on with cylinder #4. Do you have the airguides that hold the flow through the fins until the = very bottom of the cylinder? Is that cylinder slightly leaner than the others? On May 25, 2012, at 9:59 AM, = wrote: Dear subscribers, =20 A while back I reported a warmer cylinder 4 during climb at 32 MAP and = 2500 rpm. Lynn recommended I could test high boost during climb and see = if it makes a difference. =20 In the mean time I cranked up my fuel pump by approx. 1 GPH. At take-off = I see now 42.5 GPH at 38.4 MAP 2680 rpm (on a TSIO550 B which is rated = for 38 MAP at 41=8543GPH according to my manual). =20 In climb under full rpm/MAP engine stays very nice and cool. =20 Climb 2500 rpm with 32MAP: all EGTs show the same, after increasing the = fuel flow all CHTs stay generally a bit cooler but CHT 4 is still the = one that runs a little warmer. During climb when CHT4 approached 380 I = turned the high boost on =96 the CHT went down by approx. 10 degrees = back into the 360=92s. During the climb to 18000 I had the boost pump on = 3 times for may be 2 min each time. The Fuel flow increased from 30.5 to = 33 GPH. I climbed with +-170 kts at 1000 fpm. This is new: usually I = was never able to get the CHT down in climb unless I decreased the climb = rate. =20 Question: is it a reasonable practice to use the high boost for engine = cooling? How long can it run in high boost without getting damaged? =20 Craig reported earlier that he had his fuel pump modified to feed more = fuel under partial power =96 this sounds complicated and expensive and = if I don=92t have to I would rather not go there. =20 Thanks for you input =20 Ralf =20 =20 --Apple-Mail-88--1028044836 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Ralf,

I actually have my fuel = set at 45gph @2750/38.   That is the extreme high end of the = range.
..so one angle might be to add another 1.5 gph or so to = your fuel flow.   

However, from = everything else you are saying, it seems like you would want to find out = what is going on with cylinder #4.
Do you have the airguides = that hold the flow through the fins until the very bottom of the = cylinder?
Is that cylinder slightly leaner than the = others?



Dear = subscribers,
 
A = while back I reported a warmer cylinder 4 during climb at 32 MAP and = 2500 rpm. Lynn recommended I could test high boost during climb and see = if it makes a difference.
 
 
 
Climb 2500 rpm with = 32MAP: all EGTs show the same, after increasing the fuel flow all CHTs = stay generally a bit cooler but CHT 4 is still the one that runs a = little warmer. During climb when CHT4 approached 380 I turned the high = boost on =96 the CHT went down by approx. 10 degrees back into the = 360=92s. During the climb to 18000 I had the boost pump on 3 times for = may be 2 min each time. The Fuel flow increased from 30.5 to 33 GPH. I = climbed with +-170 kts at 1000 fpm.  This is new: usually I was = never able to get the CHT down in climb unless I decreased the climb = rate.
 
Question: is it a = reasonable practice to use the high boost for engine cooling? How long = can it run in high boost without getting damaged?
Craig reported earlier that he had = his fuel pump modified to feed more fuel under partial power =96 this = sounds complicated and expensive and if I don=92t have to I would rather = not go there.