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: "Charlie England ceengland7@gmail.com" Received: from mail-qv1-f43.google.com ([209.85.219.43] verified) by logan.com (CommuniGate Pro SMTP 6.3.11) with ESMTPS id 1017572 for flyrotary@lancaironline.net; Mon, 23 May 2022 10:39:18 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.219.43; envelope-from=ceengland7@gmail.com Received: by mail-qv1-f43.google.com with SMTP id c9so11551291qvx.8 for ; Mon, 23 May 2022 07:39:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :references:from:in-reply-to; bh=aEI2Mk+X03GiCd6onLo4eVidNDGkwzYChyL6L78UK40=; b=XbiAmOFzRLuDuRsqegoThKmHUfx4/Uz09suqhYTuWpC5ukbEax542y3kqhYOICyB9T XFjUypKHDGkFOuGIlCAyS7x6dcu6nNCXfvqOCE6s8CbmXugRA6dPbB9xm3VZTdWbK/5a CjNrvtInirpLzYRM98FhPYna8G7Gb19cBBckvFJstL1TitMsXXrzCSHxv/1LR1dtGNyD 7Rz2e0CPTTPUkL1LpVmTCP+4YjeiYg899TFkObtiRBeCj5GBE+m51ce6ZySl1GfWvoG5 jl4lJrxo3Pge4eY9mJuHWtzLHITjduFEeVLhiWK+NGEHUQ731c5xMV2FOhY3eFDCVeVX s03A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:references:from:in-reply-to; bh=aEI2Mk+X03GiCd6onLo4eVidNDGkwzYChyL6L78UK40=; b=u0WPyUX+1937H0KXk1p/W40gMTqJp7WMGVjMU17PC2RZpV27JoyAlMq8blaCNcQH45 VzFR993HlSe1TEbVslS8dBWlW/q5sPXhM/ZwaYFfGVx6ca6OkKc/TirthHssb0se5nZV emfskOJkOr/kYeIIRHkKYQ0HZjuT9Zj85HNV2PkNy64RDSj+PbHmBOlV6maVHIjWhkY3 NWDrumDY2eg3BKWF9NQ4eIZdLa5bqesagus9OC548HK3+f+qgcyu0ASuEiW8K2LHPyXZ L+maSiVyZiOBgMPRHs5DPtfegrJ6G8ogvqfInNCOqtWTrqm5Yy8/upxuU1qbVp3iLAJB /g8g== X-Gm-Message-State: AOAM5304d5gVPp8kBDHZF0PWmiGXZiDHi98OYzGIJMn3QlqRID6554tA vDa5hGaxc4GvCKWxkKy68JxB/fX1P+4= X-Google-Smtp-Source: ABdhPJybTIaj58ZGQy+ZEya3lOFG/CG8ov/8mdLJknFbhCZg9GT8zak8hslzqxL5JqBzptLmWlm9JQ== X-Received: by 2002:a05:6214:20e6:b0:45c:84f2:424c with SMTP id 6-20020a05621420e600b0045c84f2424cmr17306045qvk.101.1653316741757; Mon, 23 May 2022 07:39:01 -0700 (PDT) Return-Path: Received: from [192.168.1.28] ([172.58.146.171]) by smtp.googlemail.com with ESMTPSA id q186-20020a37a7c3000000b0069fd21d0b09sm4700669qke.0.2022.05.23.07.39.00 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 May 2022 07:39:01 -0700 (PDT) Content-Type: multipart/alternative; boundary="------------MNtikBFAoLlVmATmQ57jNmCq" Message-ID: <678ab8e5-148f-bc9f-37cd-2502324e9d7d@gmail.com> Date: Mon, 23 May 2022 09:38:43 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [FlyRotary] Re: Fuel pressure trending lower. Content-Language: en-US To: Rotary motors in aircraft References: In-Reply-To: X-Antivirus: Avast (VPS 220523-2, 5/23/2022), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. --------------MNtikBFAoLlVmATmQ57jNmCq Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Ah, yes; forgot about those. I thought you had your pumps in the tunnel; that's where the boost pump is mounted in the Lyc powered -4s. Don't know if the well covers are structural, but they sure have a lot of #8 screws in them. On 5/23/2022 8:20 AM, Finn Lassen finn.lassen@verizon.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. Their > covers or lids are mainly used to step on or slide your heels on when > sitting down, if not using the seat to stand on. > > Finn > > On 5/22/2022 10:42 PM, Charlie England ceengland7@gmail.com wrote: >> FWIW, neither of my purchased -4s had covers on the tunnel. >> >> On 5/22/2022 9:03 PM, Finn Lassen finn.lassen@verizon.net wrote: >>> 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" 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 or >>> not. Tracy flies without them. Others have hinged them for storage. >>> >>> Finn >>> >>> On 5/22/2022 9:13 PM, Charlie England ceengland7@gmail.com wrote: >>>> Since it's a positive displacement pump, pumped volume should be >>>> very 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 by 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 (high >>>>> 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 from >>>>> 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 pressure 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 >>>>> reads during flight to see if that could be a factor. >>>>> >>>>> Finn >>>>> >>>>> On 5/21/2022 9:01 PM, Stephen Izett stephen.izett@gmail.com wrote: >>>>>> Hi Finn >>>>>> >>>>>> I had from memory a 393 fail. Can’t recall the symptoms sorry. >>>>>> >>>>>> 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 >>>>>> engine pump. This will save amps and wear of backup pump. >>>>>> When I switch off a pump at WOT the engine dies pretty much >>>>>> instantaneously 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.net >>>>>>> wrote: >>>>>>> >>>>>>> Recently I noticed my fuel pressure being low. Noticed because >>>>>>> engine did not come up in power when advancing to full throttle. >>>>>>> Noticed mixture real lean. Checking fuel pressure as low as 28 >>>>>>> psi (normally 35 and up to 40 at full throttle). >>>>>>> >>>>>>> Going over my engine logs since first flight I now see that fuel >>>>>>> pressure has been trending lower through each flight -- more >>>>>>> pronounced on longer flights (40+ minutes). More and more >>>>>>> pronounced over the months and became really noticeable over >>>>>>> last month. Could explain why 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 was wasted energy >>>>>>> to push way more fuel than needed through the pressure regulator >>>>>>> back to the tank. >>>>>>> >>>>>>> My secondary (backup) pump is a GSL393. When turning 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 >>>>>>> >>>>>> >>>>> >>>> >>>> >>>> >>>> Virus-free. www.avast.com >>>> >>>> >>>> >>>> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> >>> >>> >> > > > -- > Homepage:http://www.flyrotary.com/ > Archive and UnSub:http://mail.lancaironline.net:81/lists/flyrotary/List.html -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --------------MNtikBFAoLlVmATmQ57jNmCq Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit
Ah, yes; forgot about those. I thought you had your pumps in the tunnel; that's where the boost pump is mounted in the Lyc powered -4s. Don't know if the well covers are structural, but they sure have a lot of #8 screws in them.

On 5/23/2022 8:20 AM, Finn Lassen finn.lassen@verizon.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. Their covers or lids are mainly used to step on or slide your heels on when sitting down, if not using the seat to stand on.

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

On 5/22/2022 9:03 PM, Finn Lassen finn.lassen@verizon.net wrote:
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" 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 or not. Tracy flies without them. Others have hinged them for storage.

Finn

On 5/22/2022 9:13 PM, Charlie England ceengland7@gmail.com wrote:
Since it's a positive displacement pump, pumped volume should be very 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 by 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 (high 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 from 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 pressure 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 reads during flight to see if that could be a factor.

Finn

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

I had from memory a 393 fail. Can’t recall the symptoms sorry.

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 engine pump. This will save amps and wear of backup pump.
When I switch off a pump at WOT the engine dies pretty much instantaneously 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.net <flyrotary@lancaironline.net> wrote:

Recently I noticed my fuel pressure being low. Noticed because engine did not come up in power when advancing to full throttle. Noticed mixture real lean. Checking fuel pressure as low as 28 psi (normally 35 and up to 40 at full throttle).

Going over my engine logs since first flight I now see that fuel pressure has been trending lower through each flight -- more pronounced on longer flights (40+ minutes). More and more pronounced over the months and became really noticeable over last month. Could explain why 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 was wasted energy to push way more fuel than needed through the pressure regulator back to the tank.

My secondary (backup) pump is a GSL393. When turning 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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