X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail02.syd.optusnet.com.au ([211.29.132.183] verified) by logan.com (CommuniGate Pro SMTP 5.1.12) with ESMTPS id 2385422 for flyrotary@lancaironline.net; Sat, 13 Oct 2007 17:36:37 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.183; envelope-from=lendich@optusnet.com.au Received: from george (d220-237-214-70.dsl.nsw.optusnet.com.au [220.237.214.70]) by mail02.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l9DLZo4m001392 for ; Sun, 14 Oct 2007 07:35:51 +1000 Message-ID: <007301c80de1$0a274e90$46d6eddc@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: FW: [FlyRotary] Re: Coolant Water Pressure Date: Sun, 14 Oct 2007 07:35:55 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0070_01C80E34.DACD3930" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0070_01C80E34.DACD3930 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable quite the surprise. Japanese engineers are expert at making sure the = design has extra safety margin. Even back in the 70's. Although they are = much better at it now. I can't imagine they are rpm sensitive 33 years = later.=20 I have heard of a lot of guys adding flow restrictions on pump = inlet, not aware they are increasing pressure drop. Particularly true = with fuel systems.=20 -al wick My pump outlet has a 5/8" hole restrictor on the outlet. Same two = water pumps for 9 years. Shifting at 9,600 RPM. No cavitation damage at = all. Generally the radiator(s) will be enough restriction to keep the = pump well below its top flow rate, and lowest inlet pressure. If there = is little or no restriction on the outlet side, the pump might cavitate = momentarily during acceleration.=20 More likely with lower total system pressure, and low restriction. = Less likely with an accumulator system and more restriction,and higher = system pressure. Less likely with low system volume. More likely with = high system volume. With just a bit of anti freeze and its anti foaming = agents, very unlikely. More likely when air remains in the system. The = pumps are mounted high on the block, and will not pump at all with a bit = of air sitting in them. It is critical that the pump be submerged prior = to start up.=20 Lynn E. Hanover Lynn, Just to clarify! - Is that with standard pulley sizes? George ( down under) -------------------------------------------------------------------------= ----- See what's new at AOL.com and Make AOL Your Homepage. -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG Free Edition.=20 Version: 7.5.488 / Virus Database: 269.14.9/1069 - Release Date: = 13/10/2007 7:26 PM ------=_NextPart_000_0070_01C80E34.DACD3930 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
quite the surprise. Japanese engineers are expert = at making=20 sure the design has extra safety margin. Even back in the 70's. Although = they=20 are much better at it now. I can't imagine they are rpm sensitive 33 = years=20 later.
 
I have heard of a lot of guys = adding flow=20 restrictions on pump inlet, not aware they are increasing pressure = drop.=20 Particularly true with fuel systems.
 
-al = wick
My pump outlet has a 5/8" hole restrictor on the outlet. Same two = water=20 pumps for 9 years. Shifting at 9,600 RPM. No cavitation damage at all. = Generally the radiator(s) will be enough restriction to keep the pump = well=20 below its top flow rate, and lowest inlet pressure. If there is little = or no=20 restriction on the outlet side, the pump might cavitate = momentarily=20 during acceleration.
 
More likely with lower total system pressure, and low = restriction. Less=20 likely with an accumulator system and more restriction,and higher = system=20 pressure. Less likely with low system volume. More likely with = high=20 system volume. With just a bit of anti freeze and its anti foaming = agents,=20 very unlikely. More likely when air remains in the system. The pumps = are=20 mounted high on the block, and will not pump at all with a bit of air = sitting=20 in them. It is critical that the pump be submerged prior to start up. =
 
Lynn E. Hanover

 
Lynn,
Just to clarify!  - Is that with standard pulley = sizes?
George ( down under)


See what's new at AOL.com=20 and Make AOL Your Homepage.


No virus found in this incoming message.
Checked by AVG Free = Edition.
Version: 7.5.488 / Virus Database: 269.14.9/1069 - = Release Date:=20 13/10/2007 7:26 PM
------=_NextPart_000_0070_01C80E34.DACD3930--