X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp111.sbc.mail.mud.yahoo.com ([68.142.198.210] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with SMTP id 1145844 for flyrotary@lancaironline.net; Thu, 08 Jun 2006 00:36:05 -0400 Received-SPF: none receiver=logan.com; client-ip=68.142.198.210; envelope-from=dcarter11@sbcglobal.net Received: (qmail 78293 invoked from network); 8 Jun 2006 04:35:19 -0000 Received: from unknown (HELO davidsdell8200) (dcarter11@sbcglobal.net@67.41.226.150 with login) by smtp111.sbc.mail.mud.yahoo.com with SMTP; 8 Jun 2006 04:35:18 -0000 Message-ID: <3f5501c68ab5$0cba7de0$6401a8c0@davidsdell8200> From: "David Carter" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Water in Gasoline Date: Wed, 7 Jun 2006 22:36:02 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_3F52_01C68A82.C14E3EF0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 This is a multi-part message in MIME format. ------=_NextPart_000_3F52_01C68A82.C14E3EF0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable My first impression of the technical paper was that the writer was off = by an order of magnitude on the amount of water that can and does = condense on inside of, for example, Cessna 172 or 182 fuel tanks in = humit Gulf Coast areas, with cooling of air during the night, and water = condensing out inside the tank. . . . Of course that is the main reason that "good airmanship" says, = "Top off the tanks before putting the plane to bed for the night (or = longer)." . . . However and notwithstanding, there are times when the tanks may = not be topped off and then you'll get more water. These comments don't detract from or relate to Barry's excellent "first = take" summary. I'm simply saying I think the author of the paper is way = low on his estimates and desensitizes his analysis of effects of = condensation of water out of humid air. David Carter ----- Original Message -----=20 From: Barry Gardner=20 To: Rotary motors in aircraft=20 Sent: Wednesday, June 07, 2006 8:33 PM Subject: [FlyRotary] Re: Water in Gasoline Ed, I read the article but it didn't give me much pause.=20 They start with the fact that gasoline with water is a problem to = engines because they stop when they try to burn water. Okay, so far, so = good. Then they point out that MBTE oxygenated gas doesn't absorb very = much water. In case of water contamination, see problem one. Ethanol and water absorb 3.8 teaspoons per gallon without a problem. = So they point out that ethanol-oxygenated gasoline is actually more = tolerant of water and, therefore, less likely to cause problems for = minor contamination. The glitch comes if one has more water than that. Then phase = separation occurs and the excess water starts to absorb ethanol out of = the gasoline. Then four-stroke motors have problem number one (i.e. not = running). But for two-stroke engines, the water-ethanol mix can displace the = gas-oil mixture THAT LUBES THE ENGINE. That's why they remark that the = effects on two-strokes can be bad--inadequate lube. My take is: a) this effect is only present for gasoline that's so contaminated = that the ethanol can't absorb all the water, b) the difference between four-strokes and two-strokes is that = four-strokes quit running whereas two-strokes quit running and can = seize, and c) if you left your OEM apex seal lube in place instead of going to = just oil-fuel mix in your gas tank, you still might be okay. More reason = to install Richard Sohn's little lube pump reservoir and just replace = those goofy oil injection nylon lines with stainless ones. In note b above, if both four-strokes and two-strokes both quit in the = case of gross water contamination, it probably feels the same to you = experienced glider pilots. But if you have really displaced all your = lube through water contamination, then two-strokers get to rebuild the = engine too. That's bad but not unexpected when one runs out of lube, no = matter how it's delivered to the engine. Barry Gardner Wheaton, IL ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Wednesday, June 07, 2006 7:37 PM Subject: [FlyRotary] Water in Gasoline I ran across this interesting article on the effects of water in = gasoline and in combination with alcohol could have on engines. = Possibly indicates that MoGas with Alcohol might be a potentially very = bad combination for 2 stroke engines in particular. But, read for = yourself if interested. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com -------------------------------------------------------------------------= --- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ ------=_NextPart_000_3F52_01C68A82.C14E3EF0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
My first impression of the technical = paper was that=20 the writer was off by an order of magnitude on the amount of water that = can and=20 does condense on inside of, for example, Cessna 172 or 182 fuel tanks in = humit=20 Gulf Coast areas, with cooling of air during the night, and water = condensing out=20 inside the tank.
. . . Of course that is the main reason = that "good=20 airmanship" says, "Top off the tanks before putting the plane to bed for = the=20 night (or longer)."
. . . However and notwithstanding, = there are times=20 when the tanks may not be topped off and then you'll get more=20 water.
 
These comments don't detract from or = relate to=20 Barry's excellent "first take" summary.  I'm simply saying I think = the=20 author of the paper is way low on his estimates and desensitizes = his=20 analysis of effects of condensation of water out of humid = air.
 
David Carter
----- Original Message -----
From:=20 Barry=20 Gardner
Sent: Wednesday, June 07, 2006 = 8:33=20 PM
Subject: [FlyRotary] Re: Water = in=20 Gasoline

Ed,
 
I read the article but it didn't give = me much=20 pause.
 
They start with the fact that = gasoline with water=20 is a problem to engines because they stop when they try to burn water. = Okay,=20 so far, so good. Then they point out that MBTE oxygenated gas doesn't = absorb=20 very much water. In case of water contamination, see problem = one.
 
Ethanol and water absorb 3.8 = teaspoons per gallon=20 without a problem. So they point out that ethanol-oxygenated gasoline = is=20 actually more tolerant of water and, therefore, less likely to cause = problems=20 for minor contamination.
 
The glitch comes if one has more = water than that.=20 Then phase separation occurs and the excess water starts to absorb = ethanol out=20 of the gasoline. Then four-stroke motors have problem number = one=20 (i.e. not running).
 
But for two-stroke engines, the = water-ethanol mix=20 can displace the gas-oil mixture THAT LUBES THE ENGINE. That's why = they remark=20 that the effects on two-strokes can be bad--inadequate = lube.
 
My take is:
a) this effect is only present for = gasoline=20 that's so contaminated that the ethanol can't absorb all the=20 water,
b) the difference between = four-strokes and=20 two-strokes is that four-strokes quit running whereas two-strokes = quit=20 running and can seize, and
c) if you left your OEM apex seal = lube in place=20 instead of going to just oil-fuel mix in your gas tank, you still = might be=20 okay. More reason to install Richard Sohn's little lube pump=20 reservoir and just replace those goofy oil injection nylon lines = with=20 stainless ones.
 
In note b above, if both four-strokes = and=20 two-strokes both quit in the case of gross water contamination, it = probably=20 feels the same to you experienced glider pilots. But if you have = really=20 displaced all your lube through water contamination, then two-strokers = get to=20 rebuild the engine too. That's bad but not unexpected when one runs = out of=20 lube, no matter how it's delivered to the engine.
 
Barry Gardner
Wheaton, IL
----- Original Message -----
From:=20 Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Wednesday, June 07, = 2006 7:37=20 PM
Subject: [FlyRotary] Water in = Gasoline

I ran across this interesting article on the = effects=20 of water in gasoline and in combination with alcohol could have on=20 engines.  Possibly indicates that MoGas with Alcohol might be a = potentially very bad combination for 2 stroke engines in = particular. =20 But, read for yourself if interested.
 
Ed
 
Ed Anderson
Rv-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com

--
Homepage:  http://www.flyrotary.com/
Archive = and=20 UnSub:  =20 = http://mail.lancaironline.net/lists/flyrotary/
------=_NextPart_000_3F52_01C68A82.C14E3EF0--