X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-pd0-f172.google.com ([209.85.192.172] verified) by logan.com (CommuniGate Pro SMTP 6.0.8) with ESMTPS id 6702699 for flyrotary@lancaironline.net; Sat, 25 Jan 2014 16:45:15 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.192.172; envelope-from=christamarmc@gmail.com Received: by mail-pd0-f172.google.com with SMTP id p10so4370355pdj.31 for ; Sat, 25 Jan 2014 13:44:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=65EUTlEclg/ah8G6Wi8lgcByTaEvnawu4jTkJG/jBNs=; b=gMlKJAF5CY99p8YY0Czg3cy1qPBauqIxj+vS2Q0zc2cCycBT0PkmcrEyyMjTbSbXK7 Nje+ifTOX8LlObMMFZ6FwuVLT1oW9I2fx3cCzUhhZD0hMrdRYVlfVuSTQOpAXNrgqSBJ ibwVbE/UsuUV7aPQIxlc9Y9dXn+TcJa/bSNC/OGSa5jPumpmySDKdEky2gjnWhzDkBvS RkKZnTk0cvUyjje2pdFr2WUTKdnLX3K0YDryTxe0untdg1zjpNknE9e1Sv+R27fxOOpc xgNxHujzTzb5LXV9utaKBWefrE0Mh2KUsBqWzJeXYvh520cXx7TscS5tUlyCC2iW0EkP YMYw== X-Received: by 10.68.226.200 with SMTP id ru8mr21797961pbc.77.1390686281158; Sat, 25 Jan 2014 13:44:41 -0800 (PST) Return-Path: Received: from [172.20.10.2] ([101.169.226.27]) by mx.google.com with ESMTPSA id hb10sm16354269pbd.1.2014.01.25.13.44.39 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sat, 25 Jan 2014 13:44:39 -0800 (PST) Subject: Re: [FlyRotary] Exhaust Leak at Turbo Outlet Flange References: From: Christamarmc Content-Type: multipart/alternative; boundary=Apple-Mail-54E4060E-E035-4D29-AAD9-D485E5AE49C0 X-Mailer: iPad Mail (9B206) In-Reply-To: Message-Id: Date: Sun, 26 Jan 2014 07:44:32 +1000 To: Rotary motors in aircraft Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) --Apple-Mail-54E4060E-E035-4D29-AAD9-D485E5AE49C0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Thanks for keeping us all informed , helps us all to make sure we look for o= ften simple overlooked areas. Cheers Christian=20 Renises 13 b rv7 Sent from my iPad On 26/01/2014, at 3:17 AM, shipchief@aol.com wrote: > During the 8th flight of my RV8 with 13B Turbo, I experienced an exhaust l= eak at the turbo exhaust flange. I mistakenly used brass exhaust nuts which= are twice as tall as regular nuts. They work great on most engines. I shoul= d have know better, as the temperature at the turbo outlet, under the insula= tion is much higher. > The brass nuts softened and deformed into a flange face at the washer! Onc= e the tension was gone, the heat & vibration did the rest. > The exhaust gasket blew where the gap was widest, at the top. > The escaping heat burned thru the insulating jacket and the stick on refle= ctive aluminum. Then the fiberglass cowl charred, I smelled that! > I was close to my destination, and high, so I was able to pull off the pow= er, put down the nosed and get on the ground without incident. > I'm disassembling it now, looks like I need 4 high temperature lock nuts a= nd a TO-4 exhaust flange gasket. I should review and improve the insulation o= ver the turbine housing. Also I need to repair the charred area of the cowl,= which might be in the form of an aluminum access hatch. --Apple-Mail-54E4060E-E035-4D29-AAD9-D485E5AE49C0 Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=utf-8
Thanks for keeping us all informed , helps us all to make sure we look for often simple overlooked areas.

Cheers
Christian 
Renises 13 b rv7

Sent from my iPad

On 26/01/2014, at 3:17 AM, shipchief@aol.com wrote:

During the 8th flight of my RV8 with 13B Turbo, I experienced an exhaust leak at the turbo exhaust flange. I mistakenly used brass exhaust nuts  which are twice as tall as regular nuts. They work great on most engines. I should have know better, as the temperature at the turbo outlet, under the insulation is much higher.
The brass nuts softened and deformed into a flange face at the washer! Once the tension was gone, the heat & vibration did the rest.
The exhaust gasket blew where the gap was widest, at the top.
The escaping heat burned thru the insulating jacket and the stick on reflective aluminum. Then the fiberglass cowl charred, I smelled that!
I was close to my destination, and high, so I was able to pull off the power, put down the nosed and get on the ground without incident.
I'm disassembling it now, looks like I need 4 high temperature lock nuts and a TO-4 exhaust flange gasket. I should review and improve the insulation over the turbine housing. Also I need to repair the charred area of the cowl, which might be in the form of an aluminum access hatch.
--Apple-Mail-54E4060E-E035-4D29-AAD9-D485E5AE49C0--