X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 17 Dec 2009 10:11:43 -0500 Message-ID: X-Original-Return-Path: Received: from imr-da01.mx.aol.com ([205.188.105.143] verified) by logan.com (CommuniGate Pro SMTP 5.3c3) with ESMTP id 4025862 for lml@lancaironline.net; Thu, 17 Dec 2009 10:07:33 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.188.105.143; envelope-from=MikeEasley@aol.com Received: from imo-da04.mx.aol.com (imo-da04.mx.aol.com [205.188.169.202]) by imr-da01.mx.aol.com (8.14.1/8.14.1) with ESMTP id nBHF6ofL013982 for ; Thu, 17 Dec 2009 10:06:50 -0500 Received: from MikeEasley@aol.com by imo-da04.mx.aol.com (mail_out_v42.5.) id q.bc3.5eabdcc4 (37254) for ; Thu, 17 Dec 2009 10:06:47 -0500 (EST) Received: from MikeNotebook (c-75-71-55-189.hsd1.co.comcast.net [75.71.55.189]) by cia-ma07.mx.aol.com (v126.13) with ESMTP id MAILCIAMA074-91864b2a4905aa; Thu, 17 Dec 2009 10:06:46 -0500 X-Original-Date: Thu, 17 Dec 2009 08:06:51 -0700 From: mikeeasley Subject: Re: [LML] Re: Oil Pressure Sender Installation (was Legacy Crash Watsonville?) X-Original-To: "Lancair Mailing List" In-Reply-To: X-Original-Message-ID: References: X-Mailer: Nexus Desktop Client 3.1.20.1 MIME-Version: 1.0 Content-Type: MULTIPART/alternative; BOUNDARY=12df0a25-47b6-4f80-bd35-51d6c2cd547e Content-Transfer-Encoding: 8bit X-AOL-IP: 75.71.55.189 X-Spam-Flag:NO X-AOL-SENDER: MikeEasley@aol.com --12df0a25-47b6-4f80-bd35-51d6c2cd547e Content-Type: TEXT/plain; charset=us-ascii Gary, I figure the restrictor fitting is the key to preventing an engine fire from a leak. Adding components like hoses and other fittings downstream from the restrictor fitting add potential failure points, but the leaking sender is probably the most likely failure point. In my engine installation, I have a T fitting and the Hobbs pressure switch attached next to the oil pressure sender, double the leak potential. One thing nice about a stock IO-550N is there are no external oil lines. The oil cooler is mounted to the engine and no turbo oil lines to be concerned about. The guys with turbos and remote mounted oil filter modifications have a lot of oil running around the engine compartment in hoses and you can't use restrictor fittings on those! But I think properly fabricated, routed and secured hoses are a reliable way to keep the oil where it belongs. Mike In a message dated 12/17/09 07:52:09 Mountain Standard Time, casey.gary@yahoo.com writes: Not that I would disagree, but...aren't these the same "VDO" senders that have been used for maybe 50 years in cars, always directly attached to the engine? A lot of those were 4-cylinder engines that have a pretty high vibration level. I've seen a lot of them fail from leakage or intermittent resistor contacts, but none from falling off the engine. So would attaching them directly to the engine via a steel restrictor fitting really be worse than using a flexible hose, with its potential leakage potential? I'm not sure. Gary, having made my own restrictor fittings. Robert, If there is a "correct" way to install the oil pressure sender, you're supposed to use a restrictor fitting on the engine, a firesleeved hose to a firewall mounted sensor. Oil pressure senders can leak, so using a restrictor fitting is key. Better to have a drip instead of a huge leak. Mounting the sender away from engine vibration will significantly increase its lifespan. I have a JPI EDM 900 engine monitor and the instructions specifically say "DO NOT MOUNT SENSOR DIRECTLY TO ENGINE" but there's no mention of a restrictor fitting. They specify an Adel clamp around the sensor attached to the firewall. Vans sells a 45 degree steel elbow restrictor fitting for about $20. Wicks has an inline brass restrictor fitting for about $6. I think a restrictor fitting is a good idea on the fuel pressure sender hose fitting too. Mike In a message dated 12/16/09 08:04:56 Mountain Standard Time, lancair-esp@ustek.com writes: From: mikeeasley [mailto:mikeeasley@aol.com] Sent: Tuesday, December 15, 2009 8:41 AM To: lml@lancaironline.net Subject: Re: [LML] Re: Legacy Crash Watsonville? I can't think on anything worse than an engine fire and it's important to discuss what to do when you have to deal with an in-flight fire. When the DAR signed off my GlaStar he pointed to the oil pressure sensor mounted directly to the engine, saying that it was not illegal but . . . the year previous a similar cantilevered positioning resulted in a fatigue failure, the oil spewed out, and when attempting to land the pilot flew into power lines. So maybe perhaps I might want to consider a change. And yeah, I did not move the plane until that was repositioned. Robert M. Simon ES-P N301ES --12df0a25-47b6-4f80-bd35-51d6c2cd547e Content-Type: TEXT/html; charset=utf-8 Content-Transfer-Encoding: 8BIT
Gary,
 
I figure the restrictor fitting is the key to preventing an engine fire from a leak.  Adding components like hoses and other fittings downstream from the restrictor fitting add potential failure points, but the leaking sender is probably the most likely failure point.  In my engine installation, I have a T fitting and the Hobbs pressure switch attached next to the oil pressure sender, double the leak potential.
 
One thing nice about a stock IO-550N is there are no external oil lines.  The oil cooler is mounted to the engine and no turbo oil lines to be concerned about.  The guys with turbos and remote mounted oil filter modifications have a lot of oil running around the engine compartment in hoses and you can't use restrictor fittings on those!  But I think properly fabricated, routed and secured hoses are a reliable way to keep the oil where it belongs.
 
Mike
 
In a message dated 12/17/09 07:52:09 Mountain Standard Time, casey.gary@yahoo.com writes:
Not that I would disagree, but...aren't these the same "VDO" senders that have been used for maybe 50 years in cars, always directly attached to the engine?  A lot of those were 4-cylinder engines that have a pretty high vibration level.  I've seen a lot of them fail from leakage or intermittent resistor contacts, but none from falling off the engine.  So would attaching them directly to the engine via a steel restrictor fitting really be worse than using a flexible hose, with its potential leakage potential?  I'm not sure.
Gary, having made my own restrictor fittings.

Robert,
 
If there is a "correct" way to install the oil pressure sender, you're supposed to use a restrictor fitting on the engine, a firesleeved hose to a firewall mounted sensor.  Oil pressure senders can leak, so using a restrictor fitting is key.  Better to have a drip instead of a huge leak.  Mounting the sender away from engine vibration will significantly increase its lifespan.
 
I have a JPI EDM 900 engine monitor and the instructions specifically say "DO NOT MOUNT SENSOR DIRECTLY TO ENGINE" but there's no mention of a restrictor fitting.  They specify an Adel clamp around the sensor attached to the firewall.
 
Vans sells a 45 degree steel elbow restrictor fitting for about $20.  Wicks has an inline brass restrictor fitting for about $6.  I think a restrictor fitting is a good idea on the fuel pressure sender hose fitting too.
 
Mike
 
 
 
 
In a message dated 12/16/09 08:04:56 Mountain Standard Time, lancair-esp@ustek.com writes:
From: mikeeasley [mailto:mikeeasley@aol.com] 
Sent: Tuesday, December 15, 2009 8:41 AM
To: lml@lancaironline.net
Subject: Re: [LML] Re: Legacy Crash Watsonville?
I can't think on anything worse than an engine fire and it's important to discuss what to do when you have to deal with an in-flight fire. 
 
  When the DAR signed off my GlaStar he pointed to the oil pressure sensor mounted directly to the engine, saying that it was not illegal but . . . the year previous a similar cantilevered positioning resulted in a fatigue failure, the oil spewed out, and when attempting to land the pilot flew into power lines.  So maybe perhaps I might want to consider a change.  And yeah, I did not move the plane until that was repositioned. 
 
Robert M. Simon
ES-P N301ES
 

 
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