X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "David COOK hoursaway1@comcast.net" Received: from resqmta-c1p-023462.sys.comcast.net ([96.102.19.34] verified) by logan.com (CommuniGate Pro SMTP 6.3.11) with ESMTPS id 1019064 for flyrotary@lancaironline.net; Mon, 23 May 2022 18:19:26 -0400 Received-SPF: pass receiver=logan.com; client-ip=96.102.19.34; envelope-from=hoursaway1@comcast.net Received: from resomta-c1p-023411.sys.comcast.net ([96.102.18.231]) by resqmta-c1p-023462.sys.comcast.net with ESMTP id tExpnDQsqhZWrtGOLnzBEo; Mon, 23 May 2022 22:19:09 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=comcast.net; s=20190202a; t=1653344349; bh=GcZPhsbOMVaGaLDyrU/iRxBPuMGxZ7M+EWiKN0D/u5s=; h=Received:Received:Date:From:To:Message-ID:Subject:MIME-Version: Content-Type; b=slyP3sK/3qhwhG3UHI716lex8TrV9oSj0JnVMg+RuZU4AEMUvxE9O4RR7IMoMqdfh hzzC31hRzoRdRYEVu1/4f9OzF9j3n4IA/pnSp+phVTY4j5PD7DjYtILeXHmeXhurVX z1KkqgfDt9zZPIL1aMjxeRh+DduXeQ43H68Szo9CJGlyVYJ/zmwI5CfTiAU9mM4en/ CnvHBHRfMuDMrTkmu4dFPGFcwEALEyBV2MvhcXnXYXpqWia/hXHIoN4gA1wvCdC0is QZSxP0qPSKly40RYK2h1hwP2/ZLkNcVNAVCYvkgemMqzuNTFgfRsNXpOqBfmjFjpAV ry1eY8N4Kj43w== Received: from oxapp-ch2f-48o.email.comcast.net ([96.117.82.173]) by resomta-c1p-023411.sys.comcast.net with ESMTPS id tGNxn2Jtm2wrrtGNxnPxfC; Mon, 23 May 2022 22:18:48 +0000 X-Xfinity-VAAS: gggruggvucftvghtrhhoucdtuddrgedvfedrjedvgddtlecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucevohhmtggrshhtqdftvghsihdpqfgfvfdppffquffrtefokffrnecuuegrihhlohhuthemuceftddunecunecujfgurhepfffhvffkjghfufggtgfrkgfoihesrgdtsggsredtjeenucfhrhhomhepffgrvhhiugcuvefqqffmuceohhhouhhrshgrfigrhidusegtohhmtggrshhtrdhnvghtqeenucggtffrrghtthgvrhhnpedvheetfeffkeejhfdukeeikeejueetueevhfekjeehvdduteeiueegjeeuleelfeenucffohhmrghinheprghvrghsthdrtghomhdpfhhlhihrohhtrghrhidrtghomhdplhgrnhgtrghirhhonhhlihhnvgdrnhgvthenucfkphepleeirdduudejrdekvddrudejfedpudeihedrvddvhedrheeirdejfeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhephhgvlhhopehogigrphhpqdgthhdvfhdqgeekohdrvghmrghilhdrtghomhgtrghsthdrnhgvthdpihhnvghtpeeliedruddujedrkedvrddujeefpdhmrghilhhfrhhomhephhhouhhrshgrfigrhidusegtohhmtggrshhtrdhnvghtpdhnsggprhgtphhtthhopedupdhrtghpthhtohepfhhlhihrohhtrghrhieslhgrnhgtrghirhhonhhlihhnvgdrnhgvth X-Xfinity-VMeta: sc=0.00;st=legit Date: Mon, 23 May 2022 18:18:45 -0400 (EDT) To: Rotary motors in aircraft Message-ID: <1783369750.152567.1653344325578@connect.xfinity.com> In-Reply-To: References: Subject: Re: [FlyRotary] Re: Fuel pressure trending lower. MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_152566_116837175.1653344325552" X-Priority: 3 Importance: Normal X-Mailer: Open-Xchange Mailer v7.10.5-Rev21 X-Originating-IP: ::ffff:165.225.56.73 X-Originating-Client: open-xchange-appsuite ------=_Part_152566_116837175.1653344325552 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Move pump grounds between rubber straps, solid on alum. bracket. Motors lik= e clean elect. pathways. I bet you could grab and turn those terms on that = rubber.=20 > On 05/23/2022 9:20 AM Finn Lassen finn.lassen@verizon.net wrote: >=20 >=20 > Traditionally the "tunnel" in the RV-4 is between your feet and legs. >=20 > The "wells" I'm talking about are just forward of the main spar. Thei= r covers or lids are mainly used to step on or slide your heels on when sit= ting down, if not using the seat to stand on. >=20 > Finn > =20 > On 5/22/2022 10:42 PM, Charlie England ceengland7@gmail.com mailto:ce= england7@gmail.com wrote: >=20 > > > FWIW, neither of my purchased -4s had covers on the t= unnel. > >=20 > > On 5/22/2022 9:03 PM, Finn Lassen finn.lassen@verizon.net mailt= o:finn.lassen@verizon.net wrote: > >=20 > > > > > Factors in my favor: > > > Pumps are located opposite side from exhaust. > > > Pumps are elevated about 1.5" from floor (plastic cradles= ). > > > However, very likely that those enclosed "foot wells" hea= t up. > > > Definitely need to investigate that. > > > I guess I could even remove the cover (lid) and just feel= with my hand during flight. > > > Seems to be some discussion whether those covers are stru= ctural or not. Tracy flies without them. Others have hinged them for storag= e. > > >=20 > > > Finn > > >=20 > > > On 5/22/2022 9:13 PM, Charlie England ceengland7@gmail.co= m mailto:ceengland7@gmail.com wrote: > > >=20 > > > > > > > Since it's a positive displac= ement pump, pumped volume should be very similar (at the same supply voltag= e) whether the engine consumes any fuel. Temp is obviously a variable. RV4 = floors get hot; at least when powered by a Lyc. ;-) > > > >=20 > > > > On 5/22/2022 7:44 PM, Finn Lassen finn.lassen@veriz= on.net mailto:finn.lassen@verizon.net wrote: > > > >=20 > > > > > > > > > Thanks Steve. > > > > >=20 > > > > > From your March/April 2017 posts it was a GSL= 392 that failed (high current draw/low pressure, even after you removed the= insect you found in the inlet). > > > > >=20 > > > > > So this afternoon I ran the pump for about an= hour. Amp draw from 3.04 to 2.86 depending on voltage. Pressure between 43= and 40 psi (also depending on voltage). No noticeable degradation. Of cour= se the difference with this test is that no fuel went to engine -- all reci= rculated through pressure regulator and back to tank. But no signs of a fai= ling pump in terms of higher current draw and less pressure. > > > > >=20 > > > > > I guess I should put a temp probe on the pump= and see what it reads during flight to see if that could be a factor. > > > > >=20 > > > > > Finn > > > > >=20 > > > > > On 5/21/2022 9:01 PM, Stephen Izett stephen.i= zett@gmail.com mailto:stephen.izett@gmail.com wrote: > > > > >=20 > > > > > > > > > > > Hi Finn > > > > > >=20 > > > > > > I had from memory a 393 fail. Can=E2=80= =99t recall the symptoms sorry. > > > > > >=20 > > > > > > I test before takeoff and then run both= pumps below 2ooo ft incase of failure. > > > > > > I plan to instal a comparator relay boa= rd in fuel pressure circuit to automatically bring on backup pump and failu= re indicator. > > > > > > So testing before flight becomes - swit= ch off and back on main engine pump. This will save amps and wear of backup= pump. > > > > > > When I switch off a pump at WOT the eng= ine dies pretty much instantaneously and don't want to be fiddling with a r= estart in the Glasair which glides like a brick with the gear out in the br= eeze. > > > > > >=20 > > > > > > Regards =20 > > > > > > Steve Izett > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > >=20 > > > > > > > > > > > > > = On 21 May 2022, at 10:30 pm, Finn Lassen finn.lassen@verizon.net mai= lto:finn.lassen@verizon.net wrote: > > > > > > >=20 > > > > > > > Recently I noticed my fuel pressu= re being low. Noticed because engine did not come up in power when advancin= g to full throttle. Noticed mixture real lean. Checking fuel pressure as lo= w as 28 psi (normally 35 and up to 40 at full throttle). > > > > > > >=20 > > > > > > > Going over my engine logs since f= irst flight I now see that fuel pressure has been trending lower through ea= ch flight -- more pronounced on longer flights (40+ minutes). More and more= pronounced over the months and became really noticeable over last month. C= ould explain why mixture tuning appeared to have changed. Nice to have engi= ne logs from practically each flight. > > > > > > >=20 > > > > > > > But why? Pump getting weaker? > > > > > > >=20 > > > > > > > My primary fuel pump is a GSL414.= I figured it was wasted energy to push way more fuel than needed through t= he pressure regulator back to the tank. > > > > > > >=20 > > > > > > > My secondary (backup) pump is a G= SL393. When turning that on, fuel pressure comes back up to where it needs = to be. > > > > > > >=20 > > > > > > > Anyone have experience with faili= ng or weak EFI pumps, particularly the GSL414? > > > > > > >=20 > > > > > > > Finn > > > > > > >=20 > > > > > > > > > > > > >=20 > > > > > >=20 > > > > > > > > > > >=20 > > > > >=20 > > > > > > > > >=20 > > > > https://www.avast.com/sig-email?utm_medium=3Demail= &utm_source=3Dlink&utm_campaign=3Dsig-email&utm_content=3Demailclient&utm_t= erm=3Dicon > > > > Virus-free. www.avast.com https://www.avast.com/sig= -email?utm_medium=3Demail&utm_source=3Dlink&utm_campaign=3Dsig-email&utm_co= ntent=3Demailclient&utm_term=3Dlink > > > >=20 > > > > > > >=20 > > >=20 > > > > >=20 > > >=20 >=20 > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/L= ist.html >=20 ------=_Part_152566_116837175.1653344325552 MIME-Version: 1.0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable =20 =20
Move pump grounds between rubber straps, solid on alum. bracket. M= otors like clean elect. pathways. I bet you could grab and turn those terms= on that rubber. 
On 05/23/2022 9:20 AM Finn Lassen finn.lassen@verizon.net <flyrotary= @lancaironline.net> wrote:


Traditionally the "tunnel" in the RV-4 is between your feet and legs.

The "wells" I'm talking about are just forward of the main spar. Th= eir covers or lids are mainly used to step on or slide your heels on when s= itting down, if not using the seat to stand on.

Finn
 
On 5/22/2022 10:42 PM, Charlie England ceengland7@gmail.com wro= te:
FWIW, neither of my purchased -4s had covers on the tunnel.

On 5/22/2022 9:03 PM, Finn Lassen finn.lassen@verizon.net w= rote:
Factors in my favor:=20
Pumps are located opposite side from exhaust.
Pumps are elevated about 1.5" from floor (plastic cradles).
However, very likely that those enclosed "foot wells" heat up.
Definitely need to investigate that.
I guess I could even remove the cover (lid) and just feel with my= hand during flight.
Seems to be some discussion whether those covers are structural o= r not. Tracy flies without them. Others have hinged them for storage.

Finn

On 5/22/2022 9:13 PM, Charlie England ceeng= land7@gmail.com wrote:
Since it's a positive displacement pump, pumped volume should be ver= y similar (at the same supply voltage) whether the engine consumes any fuel= . Temp is obviously a variable. RV4 floors get hot; at least when powered b= y a Lyc. ;-)

On 5/22/2022 7:44 PM, Finn Lassen finn.= lassen@verizon.net wrote:
Thanks Steve.

From your March/April 2017 posts it was a GSL392 that failed (h= igh current draw/low pressure, even after you removed the insect you found = in the inlet).

So this afternoon I ran the pump for about an hour. Amp draw fr= om 3.04 to 2.86 depending on voltage. Pressure between 43 and 40 psi (also = depending on voltage). No noticeable degradation. Of course the difference = with this test is that no fuel went to engine -- all recirculated through p= ressure regulator and back to tank. But no signs of a failing pump in terms= of higher current draw and less pressure.

I guess I should put a temp probe on the pump and see what it r= eads during flight to see if that could be a factor.

Finn

On 5/21/2022 9:01 PM, Stephen Izett st= ephen.izett@gmail.com wrote:
Hi Finn

I had from memory a 393 fail. Can=E2=80=99t recall the symptoms so= rry.

I test before takeoff and then run both pumps below 2ooo ft incase= of failure.
I plan to instal a comparator relay board in fuel pressure circuit= to automatically bring on backup pump and failure indicator.
So testing before flight becomes - switch off and back on main eng= ine pump. This will save amps and wear of backup pump.
When I switch off a pump at WOT the engine dies pretty much instan= taneously and don't want to be fiddling with a restart in the Glasair which= glides like a brick with the gear out in the breeze.

Regards  
Steve Izett





On 21 May 2022, at 10:30 pm, Finn Lassen finn.lassen@verizon.ne= t <flyrotary@lancaironline.net> wrote:

Recently I noticed my fuel pressure being low. N= oticed because engine did not come up in power when advancing to full throt= tle. Noticed mixture real lean. Checking fuel pressure as low as 28 psi (no= rmally 35 and up to 40 at full throttle).

Going over my engine logs since first flight I n= ow see that fuel pressure has been trending lower through each flight -- mo= re pronounced on longer flights (40+ minutes). More and more pronounced ove= r the months and became really noticeable over last month. Could explain wh= y mixture tuning appeared to have changed. Nice to have= engine logs from practically each flight.

But= why? Pump getting weaker?

My primary fuel pump is a GSL414. I figured it w= as wasted energy to push way more fuel than needed through the pressure reg= ulator back to the tank.

My secondary (backup) pump is a GSL393. When tur= ning that on, fuel pressure comes back up to where it needs to be.

Anyone have experience with failing or weak EFI = pumps, particularly the GSL414?

Finn





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