X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 25 May 2012 11:58:13 -0400 Message-ID: X-Original-Return-Path: Received: from imr-da03.mx.aol.com ([205.188.105.145] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTP id 5559849 for lml@lancaironline.net; Fri, 25 May 2012 10:58:55 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.105.145; envelope-from=n5276j@aol.com Received: from mtaomg-ma03.r1000.mx.aol.com (mtaomg-ma03.r1000.mx.aol.com [172.29.41.10]) by imr-da03.mx.aol.com (8.14.1/8.14.1) with ESMTP id q4PEw8tt017907 for ; Fri, 25 May 2012 10:58:08 -0400 Received: from core-mld002c.r1000.mail.aol.com (core-mld002.r1000.mail.aol.com [172.29.122.80]) by mtaomg-ma03.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id CDB27E000090 for ; Fri, 25 May 2012 10:58:07 -0400 (EDT) References: X-Original-To: lml@lancaironline.net Subject: Re: [LML] 360 still surging In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: steve X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CF089DEDD8420A_22C4_FE3B7_webmail-m088.sysops.aol.com" X-Mailer: AOL Webmail 36081-STANDARD Received: from 166.250.165.230 by webmail-m088.sysops.aol.com (64.12.224.203) with HTTP (WebMailUI); Fri, 25 May 2012 10:58:07 -0400 X-Original-Message-Id: <8CF089DEDD11E11-22C4-4116E@webmail-m088.sysops.aol.com> X-Originating-IP: [166.250.165.230] X-Original-Date: Fri, 25 May 2012 10:58:07 -0400 (EDT) x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:400297024:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d290a4fbf9dff6601 This is a multi-part message in MIME format. ----------MB_8CF089DEDD8420A_22C4_FE3B7_webmail-m088.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" Bernie, It is now becoming apparent that the preheating of the fuel is causing the= problem. Van's and Spruce have a shield for the fuel pump with the blast= tube. It works a lot better then the blast tube only. You should also make= a shield with blast tube for the gasolator if you cannot buy one that's fi= ts your model. Installing these covers increase's the blast tube effectiven= ess greatly along with shielding from radiant heat. You might also consider= insulating them (covers) for more effectiveness. You might also do the sam= e for the boost pump assuming it is on the firewall. I would consider all t= his an AD if it were my butt in it.=20 As some have mention fuel injection is subject to some surging. Some more t= hen others depending on the prop you are spinning. The heavier the prop (me= tal) the less the surge. Lighter (wood) the more the surge. =20 I see no need for a check valve and I hope it was not a sniffle. Sniffle v= alves are to drain fuel out of the manifolds on horizonial intakes after sh= utdown.You have two pumps that I believe have check valves built in. You sh= ould eliminate as many restrictions as possible, Did you open up and clean= the flow divider yet.? steve alderman N25SA 360 -----Original Message----- From: Berni Breen To: lml Sent: Thu, May 24, 2012 9:01 pm Subject: [LML] 360 still surging Today I made 2 changes to my airplane in an effort to remedy my surging iss= ue. Both changes were made as per suggestions from LMLers. =20 Change #1 - I removed the in line fuel filter and in line fuel check valve = formerly located in the cabin footwell of my airplane. I bought a 28" piec= e of rubber fuel line and clamped in on the void created by removing these = items. I then took the airplane for a flight during which it performed fla= wlessly as it always does in a first start scenario. I taxied back to my h= anger, shut down and let it sit for 20 minutes. I tried a restart but expe= rienced difficulty for the first time. I was not able to restart utill I t= urned the electric fuel pump on and left it on during the start. I then ta= xied and still experienced my surge issue. I was able to turn the pump off= and fast taxi. My theory on why I experienced the start issue was that the removal do the = check valve allows fuel to pass back though the system unimpeded creating t= he possibility of a loss of prime at the engine driven fuel pump. I believ= e that check valve (sniffle valve) needs to be in the fuel line. Comments? Change #2 - I installed a blast tube and directed the airflow directly onto= the engine mounted fuel pump. I started the engine (it was again cool fro= m sitting idle for a couple of hours) and went for flight #2. Again the en= gine performed flawlessly. I landed, taxied back to my hanger, shut down a= nd let the airplane sit for 20 minutes. I restarted (again had to keep the= aux fuel pump on) and began to taxi but felt the surge right away but it w= as not as pronounced a before and seemed to be lessening. During run up I = let the engine run a bit longer than usual at 1800 RPM. When I went back t= i idle...no surge. I taxied to the active...no surge and took off. Flew g= reat, landed and repeated the=20 Et sit for 20 minute thing. I restarted, taxied with a bit of a surge but = was able to eliminate it during taxi and run up. I am not ready to celebrate yet but I definitely see a marked reduction in = the severity of the surge and the ability, at least today, to eliminate any= surge by simply taxiing and or a bit of an extended run up. I believe the= blast air is the reason for the improvement. I believe I should also add = a second blast tube with the air directed at the gascolator. Does this make sense? Any and all comments welcome! Berni ----------MB_8CF089DEDD8420A_22C4_FE3B7_webmail-m088.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="us-ascii"
Bernie,
 
 It is now becoming apparent that the preheating of the fuel is c= ausing the problem.  Van's and Spruce have a  shie= ld for the fuel pump with the blast tube. It works a lot better then the bl= ast tube only. You should also make a shield with blast tube = ;for the gasolator if you cannot buy one that's fits your model. Installing= these covers increase's the blast tube effectiveness greatly along with sh= ielding from radiant heat. You might also consider insulating them (co= vers) for more effectiveness. You might also do the same for the boost pump= assuming it is on the firewall. I would consider all this an AD if it were= my butt in it.
 
As some have mention fuel injection is subject to some surging. Some m= ore then others depending on the prop you are spinning. The heavier the pro= p (metal) the less the surge. Lighter (wood) the more the surge. 
 
 I see no need for a check valve and I hope it was not a sniffle.= Sniffle valves are to drain fuel out of the manifolds on horizonial intake= s after shutdown.You have two pumps that I believe have check valves built = in. You should eliminate as many restrictions as possible, Did you open up&= nbsp; and clean the flow divider yet.?
 
 
steve alderman   N25SA   360


= -----Original Message-----
From: Berni Breen <bbreen@cableone.net>
To: lml <lml@lancaironline.net>
Sent: Thu, May 24, 2012 9:01 pm
Subject: [LML] 360 still surging

Today I made 2 = changes to my airplane in an effort to remedy my surging issue.  Both = changes were made as per suggestions from LMLers.  

Change #1 - I removed the in line fuel filter and in line fuel check v= alve formerly located in the cabin footwell of my airplane.  I bought = a 28" piece of rubber fuel line and clamped in on the void created by remov= ing these items.  I then took the airplane for a flight during which i= t performed flawlessly as it always does in a first start scenario.  I= taxied back to my hanger, shut down and let it sit for 20 minutes.  I= tried a restart but experienced difficulty for the first time.  I was= not able to restart utill I turned the electric fuel pump on and left it o= n during the start.  I then taxied and still experienced my surge issu= e.  I was able to turn the pump off and fast taxi.

My theory on why I experienced the start issue was that the removal do the = check valve allows fuel to pass back though the system unimpeded creating t= he possibility of a loss of prime at the engine driven fuel pump.  I b= elieve that check valve (sniffle valve) needs to be in the fuel line.  = ;Comments?

Change #2 - I installed a blast tube and directed the airflow directly= onto the engine mounted fuel pump.  I started the engine (it was agai= n cool from sitting idle for a couple of hours) and went for flight #2. &nb= sp;Again the engine performed flawlessly.  I landed, taxied back to my= hanger, shut down and let the airplane sit for 20 minutes.  I restart= ed (again had to keep the aux fuel pump on) and began to taxi but felt the = surge right away but it was not as pronounced a before and seemed to be les= sening.  During run up I let the engine run a bit longer than usual at= 1800 RPM.  When I went back ti idle...no surge.  I taxied to the= active...no surge and took off.  Flew great, landed and repeated the&= nbsp;
Et sit for 20 minute thing.  I restarted, taxied with a bit of a = surge but was able to eliminate it during taxi and run up.

I am not ready to celebrate yet but I definitely see a marked reductio= n in the severity of the surge and the ability, at least today, to eliminat= e any surge by simply taxiing and or a bit of an extended run up.  I b= elieve the blast air is the reason for the improvement.  I believe I s= hould also add a second blast tube with the air directed at the gascolator.=

Does this make sense?  Any and all comments welcome!

Berni
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