X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-gx0-f16.google.com ([209.85.217.16] verified) by logan.com (CommuniGate Pro SMTP 5.2.9) with ESMTP id 3230703 for flyrotary@lancaironline.net; Mon, 20 Oct 2008 11:17:43 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.217.16; envelope-from=lehanover@gmail.com Received: by gxk9 with SMTP id 9so3576454gxk.19 for ; Mon, 20 Oct 2008 08:17:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:mime-version:content-type; bh=Ss4UufC7jnCUi8+bs+4EH7JYKB5b1D6/WsZ9LbhaOFg=; b=MfGSE30EqmmN/FWQDH3+Jhbtc6PXXFN+Sv/ZUfVUkIYeYc0lI5xDC/f8nnnc9eafEM v+NbSFxn5f3HtOTyNY28O6NryxmrHd2X0Nv6t4yneVTP0SaRCKlXlhPUUJXIIuTowC18 hi3qEEjyo5cHJsd5taMOI05mJi0xcSq731Bi0= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:mime-version:content-type; b=s/bkYhrv/ZGF5jmeSYiQH7B0cbqhtmlbr1S03/Avo2CgKECbB0GO2hMXjzDGKUqM4E wYbeauMfT6jD9R8jIdceVgYKFOINxOVJFE2gcIovJzOO1nu6sXQ0MS+v9J8+DDBxoac2 8rmuBGQdfYPI6uEDeIgdBagRdkwzaUBpU50wE= Received: by 10.142.254.6 with SMTP id b6mr3113155wfi.286.1224515826220; Mon, 20 Oct 2008 08:17:06 -0700 (PDT) Received: by 10.142.87.11 with HTTP; Mon, 20 Oct 2008 08:17:06 -0700 (PDT) Message-ID: <1ab24f410810200817v64042678s18671b7c0a2ff42a@mail.gmail.com> Date: Mon, 20 Oct 2008 08:17:06 -0700 From: "Lynn Hanover" To: flyrotary@lancaironline.net Subject: Water in the fuel? MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_47239_28882549.1224515826218" ------=_Part_47239_28882549.1224515826218 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline I always like to share happy little "incidents" with others on the list in hopes we all might benefit =96 not just me {:>). I landed at Shady Bend none-stop from NC with the left tank empty and 14.7 gallons in the right tank. On the way returning from the Rotary Round up at Shady bend; I stopped to refuel at WayCross, GA as I normally do. Everything thing has been work outstandingly on the trip thus far. I took off and got up to my intended cruise of 5500 MSL (30 kt headwind there, but bumpy as heck any lower). With such a headwind, I knew the flight would be uneventful (the incidents happen when I have a tail wind). After about 30 minutes I decided to switch from my right wing tank to my left. So I turned on the boost pump and both high pressure pumps and turne= d the fuel selector switch to the left tank. Normally there is a non-event, there is no hiccup or hesitation =96 normally! Well this time things were different, the engine started to surge - big time =96 as did my heart. The fuel pressure is wiggling a sma= ll amount but clearly with pressure above 35 psi it is adequate. My mind races back to that incident a long time ago where I glided 12 mile= s engine out =96 and I decided there was no benefit to be gained by repeating that experience. So as I rapidly raced cause and solution hypothesis through my head, I reached over and turned on the cold start switch. The engine began to run almost normally, I switched cold start off and the surg= e returned. I hit "nearest" on my Garmin and turned toward the nearest airport (17 miles). Then back to the engine. It is still surging although not quite as badly as it had been =96 but still way too much to be comforta= ble with =96 and that fuel pressure is still nominally around 40 psi. What goe= s? I then turned off my secondary injectors - the engine began to run smoothly (although I don't know if this was more than a coincident of timing). So recalling my lesson learned from that earlier incident (switch tanks, dummy!), I switched back to the right tank =96 happily every thing settled down (including my heart) and the engine ran normally. After getting a bit closer to the target airport, I gathered my nerves (wha= t remained of them) and switched back to the left tank =96 there was a moment= ary burble, but then the engine started running normally and did so for the res= t of the flight burning 10 gallons out of that tank. Naturally, I am trying to figure out what could possibility have cause this momentary hiccup. Here is the best I can come up with. I landed at Shady bend with the left tank with approx =BE gallon in it. It= so happens the gas cap on that tank is in need of an O ring replacement as I noticed a small amount of fuel streaming from the cap area. Well, the aircraft set outside through a few light rain showers while at Shady Bend. I believe that water may have seeped through the cap and collected in the tank. (No, I did not do a drain of my tanks checking for water as I should have). I used to do it religiously, but after 8 years of so of never finding a single drop of water, I had lapsed in that check. No excuses =96 just the facts. So if a =BD cup or water or so had gotten into that empty tank, it would naturally have settled at the bottom =96 right next to the fuel pick up. I refueled at WayCross putting fuel into both tanks =96 no problem with the right tank (with a non-leaking cap). So I believe that I took off with som= e amount of water in the left tank. When I switched fuel tanks that slug of water was sitting right there waiting to be sucked into the system. This i= s why (I believe) the fuel pressure did not go down as it would have if there had been no liquid being pumped through the system. So it basically took = a few hair raising moments to suck all the water through the system and into the engine =96 then all was well. I am not certain why hitting the "cold Start" switch would have made any difference, but I did turn it on twice and each time the engine settled down. Also when the secondary injectors were momentarily turned off the engine smoothed out. It may have to do with injecting water into the secondaries (which are positioned further away from the engine) and perhaps the evaporative effect was sufficient to freeze the water vapor??? Don't know, but I am convinced that water in the fuel was the most likely cause. I think the principal point is that had I done the fuel drain according to Hoyle I would have likely discovered the water and drained it. So once again, a bit red-faced to admit to failing to follow long established check-list procedures (I know none of the rest of you do that), I found an interesting "incident" to relate to the list. Fly Safely out there =96 Ya' hear! Ed *It is so nice of you to investigate every known failure mode, so the rest of us lessor pilots don't have to. *Thank you............ ** *The water injected, is displacing a like volume of fuel. It is not actuall= y the water that causes the stumble, but the fact that the engine is starved for fuel (over lean mixture). So the cold start adds fuel and the engine runs again. * ** *Lynn E. Hanover* Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com ------=_Part_47239_28882549.1224515826218 Content-Type: text/html; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline

I always like to share hap= py little "incidents" with others on the list in hopes we all might benefit= =96 not just me {:>).  I landed at Shady Bend none-stop from NC wi= th the left tank empty and 14.7 gallons in the right tank. 

 

On the way returning from the Rotary Round = up at Shady bend; I stopped to refuel at WayCross, GA as I normally do.&nbs= p; Everything thing has been work outstandingly on the trip thus far.

 

I took off and got up to my intended cruise= of 5500 MSL (30 kt headwind there, but bumpy as heck any lower).  Wit= h such a headwind, I knew the flight would be uneventful (the incidents hap= pen when I have a tail wind).    After about 30 minutes I de= cided to switch from my right wing tank to my left.  So I turned on th= e boost pump and both high pressure pumps and turned the fuel selector swit= ch to the left tank.

 

Normally there is a non-event, there is no = hiccup or hesitation =96 normally!   Well this time things were d= ifferent, the engine started to  surge - big time =96 as did my heart.=   The fuel pressure is wiggling a small amount but clearly with pressu= re above 35 psi it is adequate.

 

 My mind races back to that incident a= long time ago where I glided 12 miles engine out =96 and I decided there w= as no benefit to be gained by repeating that experience.  So as I rapi= dly raced cause and solution hypothesis through my head, I reached over and= turned on the cold start switch.  The engine began to run almost norm= ally, I switched cold start off and the surge returned.  I hit "neares= t" on my Garmin and turned toward the nearest airport (17 miles).  The= n back to the engine.  It is still surging although not quite as badly= as it had been =96 but still way too much to be comfortable with =96 and t= hat fuel pressure is still nominally around 40 psi.  What goes?  =

 

I then turned off my secondary injectors - = the engine began to run smoothly (although I don't know if  this was m= ore than a coincident of timing).  So recalling my lesson learned from= that earlier incident (switch tanks, dummy!), I switched back to the right= tank =96 happily every thing settled down (including my heart) and the eng= ine ran normally.

 

After getting a bit closer to the target ai= rport, I gathered my nerves (what remained of them) and switched back to th= e left tank =96 there was a momentary burble, but then the engine started r= unning normally and did so for the rest of the flight burning 10 gallons ou= t of that tank.

 

Naturally, I am trying to figure out what c= ould possibility have cause this momentary hiccup.  Here is the best I= can come up with.

 

I landed at Shady bend with the left tank w= ith approx =BE gallon in it.  It so happens the gas cap on that tank i= s in need of an O ring replacement as I noticed a small amount of fuel stre= aming from the cap area.  Well, the aircraft set outside through a few= light rain showers while at Shady Bend.  I believe that water may hav= e seeped through the cap and collected in the tank.  (No, I did not do= a drain of my tanks checking for water as I should have).  I used to = do it religiously, but after 8 years of so of never finding a single drop o= f water, I had lapsed in that check.  No excuses =96 just the facts.

 

So if a =BD cup or water or so had gotten i= nto that empty tank, it would naturally have settled at the bottom =96 righ= t next to the fuel pick up.  I refueled at WayCross putting fuel into = both tanks =96 no problem with the right tank (with a non-leaking cap).&nbs= p; So I believe that I took off with some amount of water in the left tank.=   When I switched fuel tanks that slug of water was sitting right ther= e waiting to be sucked into the system.  This is why (I believe) the f= uel pressure did not go down as it would have if there had been no liquid b= eing pumped through the system.   So it basically took a few hair= raising moments to suck all the water through the system and into the engi= ne =96 then all was well.

 

I am not certain why hitting the "cold Star= t" switch would have made any difference, but I did turn it on twice and ea= ch time the engine settled down.  Also when the secondary injectors we= re momentarily turned off the engine smoothed out.  It may have to do = with injecting water into the secondaries (which are positioned further awa= y from the engine) and perhaps the evaporative effect was sufficient to fre= eze the water vapor???  Don't know, but I am convinced that water in t= he fuel was the most likely cause.

 

I think the principal point is that had I d= one the fuel drain according to Hoyle I would have likely discovered the wa= ter and drained it.  So once again, a bit red-faced to admit to failin= g to follow long established check-list procedures (I know none of the rest= of you do that), I found an interesting "incident" to relate to the list.<= /span>

 

Fly Safely out there =96 Ya' hear!=
 
 

Ed

It is so nice of you to investiga= te every known failure mode, so the rest of us lessor pilots don't have= to. Thank you............
 
The water injected, is displacing= a like volume of fuel. It is not actually the water that causes the stumbl= e, but the fact that the engine is starved for fuel (over lean mixture). So= the cold start adds fuel and the engine runs again. <= /font>
 
Lynn E. Hanover

 

Ed Anderson

Rv-6A N494BW Rotary Powered

Matthews, NC

eander= son@carolina.rr.com

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