X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf23aec.mail.bellsouth.net ([205.152.59.71] verified) by logan.com (CommuniGate Pro SMTP 4.3.4) with ESMTP id 989782 for flyrotary@lancaironline.net; Thu, 09 Jun 2005 07:52:03 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.71; envelope-from=sladerj@bellsouth.net Received: from ibm66aec.bellsouth.net ([65.8.33.158]) by imf23aec.mail.bellsouth.net with ESMTP id <20050609115108.RIGT8541.imf23aec.mail.bellsouth.net@ibm66aec.bellsouth.net> for ; Thu, 9 Jun 2005 07:51:08 -0400 Received: from JSLADE ([65.8.33.158]) by ibm66aec.bellsouth.net with ESMTP id <20050609115107.ONUK5308.ibm66aec.bellsouth.net@JSLADE> for ; Thu, 9 Jun 2005 07:51:07 -0400 From: "John Slade" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: Very strange problem after installing new turbo Date: Thu, 9 Jun 2005 07:51:06 -0400 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0123_01C56CC7.FDE4D010" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 This is a multi-part message in MIME format. ------=_NextPart_000_0123_01C56CC7.FDE4D010 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Dave, That is a strange one. I've had rpm drop from things like blown intake hoses, but the rpm didn't come back until the hose was fixed. Most of the problems you listed might cause an rpm "wall", but not a repeatable drop. This might not make much sense, but it sounds like something giving under pressure to me. What could "give under pressure", but then return to normal when pressure is removed? Something like a radiator pressure cap, a pop-off valve....an O ring? The other thing I might suspect would be something in the ignition tuning that's triggered at the peak rpm. A timing thing? See if retarding the ignition changes things. Just SWAGs. Regards, John ------=_NextPart_000_0123_01C56CC7.FDE4D010 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Dave,
That=20 is a strange one. I've had rpm drop from things like blown intake hoses, = but the=20 rpm didn't come back until the hose was fixed.
Most=20 of the problems you listed might cause an rpm "wall", but not a = repeatable=20 drop. This might not make much sense, but it sounds like something = giving under=20 pressure to me. What could "give under pressure", but then return to = normal when=20 pressure is removed? Something like a radiator pressure cap, a pop-off=20 valve....an O ring?
 
The=20 other thing I might suspect would be something in the ignition tuning = that's=20 triggered at the peak rpm. A timing thing?
See=20 if retarding the ignition changes things.
 
Just=20 SWAGs.
Regards,
John
 
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