X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from sccrmhc12.comcast.net ([63.240.76.22] verified) by logan.com (CommuniGate Pro SMTP 4.3.6) with ESMTP id 624147 for flyrotary@lancaironline.net; Wed, 03 Aug 2005 19:16:24 -0400 Received-SPF: none receiver=logan.com; client-ip=63.240.76.22; envelope-from=n3773@comcast.net Received: from rv8 (c-24-21-140-241.hsd1.or.comcast.net[24.21.140.241]) by comcast.net (sccrmhc12) with SMTP id <2005080323152901200qlhpie>; Wed, 3 Aug 2005 23:15:39 +0000 Message-ID: <000a01c59881$43080790$f18c1518@rv8> Reply-To: "kevin lane" From: "kevin lane" To: "Rotary motors in aircraft" References: Subject: further testing - -lycoming O-320 Date: Wed, 3 Aug 2005 16:15:25 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01C59846.8E4C39A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0007_01C59846.8E4C39A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable my engine continues to baffle me and everyone else on the airport. I = would send it to a mechanic, but I've spoken with all of them and they = have no ideas either. it continues to look like fuel starvation, but no = gauges support this theory. it runs at 2150rpm, burning 11.5-12.3 gals = per hr, 3 lbs fuel pressure, for about 2 minutes then stumbles(and will = die unless I reduce the throttle to 1500rpm. )the stumbling occurs = when cht's are hitting 375 - 410. continued running at 1500 allows the = cht's to climb, so I have to shut things down. the same behavior = occurred when I flew the plane the first two times (until I realized I = could duplicate the problem on the ground) I have a new carb(ma4spa) = and 4 rebuilt cyls (on which I am attempting to set the rings, = unfortunately) if I run the engine at less than full rich the engine = won't stumble before temps hit 400+ and I have to pull power. I bypassed my fuel filters with no difference. I installed new filters = that have a core of little brass balls stuck together and seemingly much = better flow than the other filter(no angles either, just straight flow) I cleaned and backflushed the fuel pickups and vents, ran with the gas = caps off(no diff). my fuel flow is not changing(until it sputters back = to 1500rpm), so my idea that the carb bowl was slowly not being refilled = doesn't show up. the same problem existed before I had the cyls rebuilt = and welded, so I doubt that stuck valves/weak springs are to blame. = also, that would show problems from the start, not a few minutes later. everyone wants to blame the electronic ig. switching between mag and = elec. during the first minute shows no diff. switching after it starts = to falter shows no diff. pulling back to 1500rpm after falter shows no = diff. I can't believe I have a spark or timing problem because there = are no times when one works and the other doesn't. my slick mag is = brand new also. I haven't tried new plugs yet, the current ones are = new, although I've heard many stories of bad new plugs (hey, what do you = want for $20?) my 1" dia. cheapy van's fuel pressure meter is now showing 3 lbs. I = removed the pressure regulator. in the past it used to show 8lbs = pressure (hence I installed the regulator)and my carb showed signs of = leakage which is one reason I replaced it. I have no idea why it shows = only 3 lbs now. I tried plumbing the carb directly from a gas can. I = forgot to switch the fuel line off and shot fuel clear out on the wing = when the engine started. I would guess that the mech. fuel pump is = working correctly. the facet elec pump will pump about 1 gallon in 2 = minutes when pumping into a gas can thru the mechanical pump. it makes = no diff. if I run the facet or not. I have bypassed the mech. pump and = run just with the facet, no diff., in fact, when I shut off the facet = the engine still runs until the bowl burns down, maybe 30 sec.? it is hard to believe that both the auto plugs and aero plugs are = simultaneously failing due to heat. I could fly the plane at less than = full rich to see how long it would fly I suppose, but that seems = unnecessarily risky. I've had two "lucky" flights so far. I checked for induction leaks(pressurized and soap solution) and found = nothing. I am out of ideas. this problem is just kicking my butt. hopefully = one of you guys will spark an new idea or theory for me. Kevin Lane Portland, OR e-mail-> n3773@comcast.net ------=_NextPart_000_0007_01C59846.8E4C39A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
my engine continues to baffle = me and=20 everyone else on the airport.  I would send it to a mechanic, but = I've=20 spoken with all of them and they have no ideas either.  it = continues to=20 look like fuel starvation, but no gauges support this theory.  it = runs at=20 2150rpm, burning 11.5-12.3 gals per hr, 3 lbs fuel pressure, for about 2 = minutes=20 then stumbles(and will die unless I reduce the throttle to = 1500rpm.  )the=20 stumbling  occurs when cht's are hitting 375 - 410.  continued = running=20 at 1500 allows the cht's to climb, so I have to shut things down.  = the same=20 behavior occurred when I flew the plane the first two times (until I = realized I=20 could duplicate the problem on the ground)  I have a new = carb(ma4spa) and 4=20 rebuilt cyls (on which I am attempting to set the rings, = unfortunately)  if=20 I run the engine at less than full rich the engine won't stumble before = temps=20 hit 400+ and I have to pull power.
I bypassed my fuel filters = with no=20 difference.  I installed new filters that have a core of little = brass balls=20 stuck together and seemingly much better flow than the other = filter(no=20 angles either, just straight flow)
I cleaned and backflushed the = fuel=20 pickups and vents, ran with the gas caps off(no diff).  my fuel = flow is not=20 changing(until it sputters back to 1500rpm), so my idea that the carb = bowl was=20 slowly not being refilled doesn't show up.  the same problem = existed before=20 I had the cyls rebuilt and welded, so I doubt that stuck valves/weak=20 springs are to blame.  also, that would show problems from the = start,=20 not a few minutes later.
everyone wants to blame the = electronic=20 ig.  switching between mag and elec.  during the first minute = shows no=20 diff.  switching after it starts to falter shows no diff.  = pulling=20 back to 1500rpm after falter shows no diff.  I can't believe I = have a=20 spark or timing problem because there are no times when one works and = the other=20 doesn't.  my slick mag is brand new also.  I haven't tried new = plugs=20 yet, the current ones are new, although I've heard many stories of bad = new plugs=20 (hey, what do you want for $20?)
my 1" dia. cheapy van's fuel = pressure=20 meter is now showing 3 lbs.  I removed the pressure = regulator.  in the=20 past it used to show 8lbs pressure (hence I installed the regulator)and = my carb=20 showed signs of leakage which is one reason I replaced it.  I have = no idea=20 why it shows only 3 lbs now.  I tried plumbing the carb directly = from a gas=20 can.  I forgot to switch the fuel line off and shot fuel clear out = on the=20 wing when the engine started.  I would guess that the mech. fuel = pump is=20 working correctly.  the facet elec pump will pump about 1 gallon in = 2=20 minutes when pumping into a gas can thru the mechanical pump.  it = makes no=20 diff. if I run the facet or not.  I have bypassed the mech. pump = and run=20 just with the facet, no diff., in fact, when I shut off the facet the = engine=20 still runs until the bowl burns down, maybe 30 sec.?
it is hard to believe that = both the auto=20 plugs and aero plugs are simultaneously failing due to heat.  I = could fly=20 the plane at less than full rich to see how long it would fly I suppose, = but=20 that seems unnecessarily risky.  I've had two "lucky" flights so=20 far.
I checked for induction = leaks(pressurized=20 and soap solution) and found nothing.
    I am out = of=20 ideas.  this problem is just kicking my butt.  hopefully one = of you=20 guys will spark an new idea or theory for me.
Kevin Lane  Portland, OR
e-mail-> n3773@comcast.net
 
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