X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 10 Apr 2012 16:07:22 -0400 Message-ID: X-Original-Return-Path: Received: from imr-da01.mx.aol.com ([205.188.105.143] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTP id 5474192 for lml@lancaironline.net; Mon, 09 Apr 2012 12:25:38 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.105.143; envelope-from=Sky2high@aol.com Received: from mtaomg-mb01.r1000.mx.aol.com (mtaomg-mb01.r1000.mx.aol.com [172.29.41.72]) by imr-da01.mx.aol.com (8.14.1/8.14.1) with ESMTP id q39GOsko013624 for ; Mon, 9 Apr 2012 12:24:54 -0400 Received: from core-mtc001b.r1000.mail.aol.com (core-mtc001.r1000.mail.aol.com [172.29.235.1]) by mtaomg-mb01.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 3C36FE000085 for ; Mon, 9 Apr 2012 12:24:54 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: <8fef.715f310b.3cb46756@aol.com> X-Original-Date: Mon, 9 Apr 2012 12:24:54 -0400 (EDT) Subject: Re: [LML] Re: Engine "surge" issue X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_8fef.715f310b.3cb46756_boundary" X-Mailer: AOL 9.6 sub 168 X-Originating-IP: [67.175.156.123] x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:437666016:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d29484f830d5619d5 --part1_8fef.715f310b.3cb46756_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Berni, Check engine timing. Check for induction system air leaks. During the surging, does your fuel pressure display indicate changes in pressure? How about fuel flow? Fuel flow is typically sensed in the line that feeds the spider, thus nearer the end of the fuel's trip to the cylinder. Fuel pressure is typically sensed between the engine pump and throttle body. In some cases you may want to investigate the route from the firewall to the fuel pressure sensor. That is, thru gascolator/filter, boost pump and engine pump. The area betwixt the firewall and rear engine baffling can build up quite a bit of heat because of dead air. You may want to consider a blast tube on one or more of these components. Fire shielding all fluid lines is a good thing and protects from radiated heat, but also retains heat not dissipated by a slow flow of fresh cool fuel (idle flow). Usually, heat-soaking of the engine pump can occur after a shut-down and it may cavitate a bit until cooled by the fuel flow. Usually, turning on the boost pump raises the fuel pressure enough to eliminate vapor bubble formation or forces such bubbles back into the fuel. It is serious if that doesn't resolve surging. Consider these possibilities and investigate further. Scott Krueger In a message dated 4/9/2012 10:55:38 A.M. Central Daylight Time, randylsnarr@yahoo.com writes: Berni, 100 octane fuel boils at a very low temp. Fuel is boiling in the injection lines when the engine is hot when you are idling. When you are above idle there is enough fuel traversing the fuel lines to keep them under the boiling point which is why you only get this this at idle when the engine is hot. This was explained to me by don Rivera at airflow performance, he designed the bendix injection system and is the guy who designed the airflow performance system as well so he knows what he is talking about. This same reason is responsible for the hot start issues in our fuel injection set ups. This is normal... Randy Snarr N694RS Sent from my iPad On Apr 8, 2012, at 8:37 PM, Berni Breen wrote: > Whenever my GAMI injected IO360 powered Lancair 360 is really heated up, following a flight and only a short time to cool down (less than 30 minutes) and restarted, the engine will surge during idle and taxi. Again this only happens when the engine is hot, has been shut down and restarted. The issue never occurs when the airplane (engine) is started for the first time on any given day (super hot day or super cold day). > > Since I feel the issue is fuel related I tried leaning and use of the electronic fuel pump during idle and taxi with zero improvement. The engine runs very badly with a pronounced surge. If I get on the runway and give the engine full throttle, the engine will develop good power and lift off as if there were no issue...that is until yesterday when the engine just about quit 2000' into my takeoff roll. I aborted the takeoff, did some high speed taxiing and then took off 3 minutes later (no shutdown). > > Today I took off, climbed aggressively to get the engine good and hot and landed. I shutdown, let the engine sit for about 10 minutes, restarted and once again experienced the surge during idle and or taxiing. I removed the upper and lower cowl but am still not able to identify the cause of my issue. > > Clearly I have an issue that is caused by heat affecting fuel. All of my fuel lines are heat shielded. Can anyone offer suggestions or ideas that I can try? > > Berni -- For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html --part1_8fef.715f310b.3cb46756_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Berni,
 
 
Check engine timing.
Check for induction system air leaks.
 
During the surging, does your fuel pressure display indicate changes i= n=20 pressure?  How about fuel flow?  Fuel flow is typically sensed in= the=20 line that feeds the spider, thus nearer the end of the fuel's trip to the= =20 cylinder.  Fuel pressure is typically sensed between the engine pump a= nd=20 throttle body. 
 
In some cases you may want to investigate the route from the firewall = to=20 the fuel pressure sensor.  That is, thru gascolator/filter, boost= pump=20 and engine pump.  The area betwixt the firewall and rear engine baffli= ng=20 can build up quite a bit of heat because of dead air.  You may want to= =20 consider a blast tube on one or more of these components.  Fire shield= ing=20 all fluid lines is a good thing and protects from radiated heat, but also= =20 retains heat not dissipated by a slow flow of fresh cool fuel (idle=20 flow).  Usually, heat-soaking of the engine pump can occur after a=20 shut-down and it may cavitate a bit until cooled by the fuel flow. =20 Usually, turning on the boost pump raises the fuel pressure enough to elimi= nate=20 vapor bubble formation or forces such bubbles back into the=20 fuel.  It is serious if that doesn't resolve surging.
 
Consider these possibilities and investigate further.
 
Scott Krueger
 
 
In a message dated 4/9/2012 10:55:38 A.M. Central Daylight Time,=20 randylsnarr@yahoo.com writes:
= Berni,=20 100 octane fuel boils at a very low temp. Fuel is boiling in the injectio= n=20 lines when the engine is hot when you are idling. When you are above idle= =20 there is enough fuel traversing the fuel lines to keep them under the boi= ling=20 point which is why you only get this this at idle when the engine is hot.= =20

This was explained to me by don Rivera at airflow performance, he= =20 designed the bendix injection system and is the guy who designed the airf= low=20 performance system as well so he knows what he is talking about. This sam= e=20 reason is responsible for the hot start issues in our fuel injection set= =20 ups.
This is normal...
Randy Snarr
N694RS


Sent from = my=20 iPad

On Apr 8, 2012, at 8:37 PM, Berni Breen=20 <bbreen@cableone.net> wrote:

> Whenever my GAMI injected = IO360=20 powered Lancair 360 is really heated up, following a flight and only a sh= ort=20 time to cool down (less than 30 minutes) and restarted, the engine will s= urge=20 during idle and taxi.  Again this only happens when the engine is ho= t,=20 has been shut down and restarted.  The issue never occurs when the= =20 airplane (engine) is started for the first time on any given day (super h= ot=20 day or super cold day).
>
> Since I feel the issue is fuel= =20 related I tried leaning and use of the electronic fuel pump during idle a= nd=20 taxi with zero improvement.  The engine runs very badly with a prono= unced=20 surge.  If I get on the runway and give the engine full throttle, th= e=20 engine will develop good power and lift off as if there were no issue...t= hat=20 is until yesterday when the engine just about quit 2000' into my takeoff= =20 roll.  I aborted the takeoff, did some high speed taxiing and then t= ook=20 off 3 minutes later (no shutdown).
>
> Today I took off, cli= mbed=20 aggressively to get the engine good and hot and landed.  I shutdown,= let=20 the engine sit for about 10 minutes, restarted and once again experienced= the=20 surge during idle and or taxiing.  I removed the upper and lower cow= l but=20 am still not able to identify the cause of my issue.
>
> Cle= arly=20 I have an issue that is caused by heat affecting fuel.  All of my fu= el=20 lines are heat shielded.  Can anyone offer suggestions or ideas that= I=20 can try?
>
> Berni

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