Return-Path: Received: from smtp812.mail.sc5.yahoo.com ([66.163.170.82] verified) by logan.com (CommuniGate Pro SMTP 4.1.8) with SMTP id 3054961 for flyrotary@lancaironline.net; Tue, 02 Mar 2004 15:17:18 -0500 Received: from unknown (HELO Davidscmptr) (dcarter11@sbcglobal.net@64.219.115.116 with login) by smtp812.mail.sc5.yahoo.com with SMTP; 2 Mar 2004 20:17:17 -0000 Message-ID: <046b01c40093$4d379fa0$6401a8c0@Davidscmptr> Reply-To: "David Carter" From: "David Carter" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: overflow connections Date: Tue, 2 Mar 2004 14:16:52 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 To continue to beat up on this "air vent line from top of engine" - its been made clear that the line should not be large. I'd treat it like I would a "direct oil pressure gage": If the oil line to gage breaks, you don't want to dump all your engine oil out a big broken line, so folks use very small lines and even put in restrictors. Well, in this air/steam vent line, the issue is not breaking and dumping - rather, it is "bypassing the radiator". So, to minimize coolant that doesn't get cooled, then either use the smallest possible line, or, as in the oil pressure tubing, put in a restrictor. Air doesn't need much of a hole to flow up to your vent tank. For my education, Kelly, how big is a -3 hose? 3/16 ID? David ----- Original Message ----- From: To: "Rotary motors in aircraft" Sent: Tuesday, March 02, 2004 12:14 PM Subject: [FlyRotary] Re: overflow connections > > The input I got about the expansion tank was to plumb the lower connection > > down to the radiator and the upper connection to the top of the block. > > That's what I did, and apart from the problems I had with the thermostat, it > > seems to work fine. I have a 23 lb cap on the expansion tank and a small > > overflow bottle. > > > > Regards, > > john > > > Paul and John, > > Let me expand on this subject. The input I have said to plumb the bottom > fitting of the expansion tank to input (suction side) of the water pump/radiator > to keep system pressure seen by the pressure cap to a minimum. The upper expansion > tank fitting should be small (-3 an hose or not over 3/16" I.D.) and connected > as John said to the top of the engine block. Its function is to bleed any trapped > air in the system to the tank. IMHO > > Kelly Troyer >