Return-Path: Sender: (Marvin Kaye) To: lml@lancaironline.net Date: Sun, 18 Apr 2004 15:54:36 -0400 Message-ID: X-Original-Return-Path: Received: from imo-m24.mx.aol.com ([64.12.137.5] verified) by logan.com (CommuniGate Pro SMTP 4.2b2) with ESMTP id 3176843 for lml@lancaironline.net; Sun, 18 Apr 2004 08:58:16 -0400 Received: from Sky2high@aol.com by imo-m24.mx.aol.com (mail_out_v37_r1.2.) id q.66.3f3aaa12 (3310) for ; Sun, 18 Apr 2004 08:58:12 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: <66.3f3aaa12.2db3d563@aol.com> X-Original-Date: Sun, 18 Apr 2004 08:58:11 EDT Subject: Re: [LML] Re: Exhaust failure X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1082293091" X-Mailer: 9.0 for Windows sub 4060 -------------------------------1082293091 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 4/17/2004 8:54:29 PM Central Standard Time, marv@lancaironline.net writes: It 's a style III/IV-I for a lycoming IO 320 D1B, the crack is at the junction of the pipes coming from cylinder 1 and 2. The tailpipes aren't tied together. This exhaust come from Snowline. No, I don't use anything. No anti-seize (I don't know this product) and no exhaust insulating wrap.echappement Patrick Patrick, I have a type IV - slightly different configuration than your pictures show. On mine, the slip joint for cyls 1 & 2 shows movement of about 1/8 th inch and was liberally coated with anti-seize before assembly. Since I can only see the movement marks when the pipes are cold, I conclude that they are pushed together during flight conditions and if they couldn't slip that would place strain somewhere on the pipe. However, its appears that your crack is on the top - as though the pipe was being worked up and down? Some people have supported the pipes at the firewall with an automotive type hanger and some (like me) have tied the tail pipes together with a stainless steel band squeezed in the middle. I wonder if there is some interaction between the engine vibration, exhaust pulses, prop air pulses, loose tail pipe and the weight of the long pipe that could lead to such a crack. I did have the weld at a Y-joint crack on a new engine/pipe combination after less than 18 hours of flight, but that was caused by the #4 cylinder pipe hanging down 1 inch (for some unknown length of time) because the mechanic failed to use lock washers when the pipes were mounted. Scott Krueger AKA Grayhawk Sky2high@aol.com II-P N92EX IO320 Aurora, IL (KARR) LML, where ideas collide and you decide! -------------------------------1082293091 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 4/17/2004 8:54:29 PM Central Standard Time,=20 marv@lancaironline.net writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>It 's a=20 style III/IV-I for a lycoming IO 320 D1B, the crack is at the junction of=20 the pipes coming from cylinder 1 and 2.
The tailpipes aren't tied=20 together. This exhaust come from Snowline.
No, I don't use anything. No= =20 anti-seize (I don't know this product) and no
exhaust insulating=20 wrap.echappement

Patrick
Patrick,
 
I have a type IV - slightly different configuration than your pictures=20 show.  On mine, the slip joint for cyls 1 & 2 shows movement of abo= ut=20 1/8 th inch and was liberally coated with anti-seize before assembly. =20 Since I can only see the movement marks when the pipes are cold, I conclude=20= that=20 they are pushed together during flight conditions and if they couldn't slip=20= that=20 would place strain somewhere on the pipe.  However, its appears that yo= ur=20 crack is on the top - as though the pipe was being worked up and=20 down? 
 
Some people have supported the pipes at the firewall with an automotive= =20 type hanger and some (like me) have tied the tail pipes together with a=20 stainless steel band squeezed in the middle.  I wonder if there is some= =20 interaction between the engine vibration, exhaust pulses, prop air puls= es,=20 loose tail pipe and the weight of the long pipe that could lead to such= a=20 crack. 
 
I did have the weld at a Y-joint crack on a new engine/pipe combination= =20 after less than 18 hours of flight, but that was caused by the #4 cylinder p= ipe=20 hanging down 1 inch (for some unknown length of time) because the mecha= nic=20 failed to use lock washers when the pipes were mounted.=20
 
Scott Krueger=20 AKA Grayhawk
Sky2high@aol.com
II-P N92EX IO320 Aurora, IL=20 (KARR)

LML, where ideas collide and you=20 decide!
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