Return-Path: Received: from imf16aec.mail.bellsouth.net ([205.152.59.64] verified) by logan.com (CommuniGate Pro SMTP 4.3c1) with ESMTP id 725107 for flyrotary@lancaironline.net; Fri, 11 Feb 2005 12:48:55 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.64; envelope-from=sqpilot@bellsouth.net Received: from [209.214.45.60] by imf16aec.mail.bellsouth.net (InterMail vM.5.01.06.11 201-253-122-130-111-20040605) with ESMTP id <20050211174800.GTGI1983.imf16aec.mail.bellsouth.net@[209.214.45.60]> for ; Fri, 11 Feb 2005 12:48:00 -0500 Received: from 127.0.0.1 (AVG SMTP 7.0.300 [265.8.7]); Fri, 11 Feb 2005 11:47:37 -0600 Message-ID: <002601c51061$b80c67a0$3c2dd6d1@paul52u7f5qyav> From: "Paul" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Microtech EFI and Tuning, was Re: [FlyRotary] Re: Bad day at the airport Date: Fri, 11 Feb 2005 11:46:23 -0600 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 Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=======AVGMAIL-420CEFB90AC3=======" --=======AVGMAIL-420CEFB90AC3======= Content-Type: multipart/alternative; boundary="----=_NextPart_000_0023_01C5102F.4F5F7350" ------=_NextPart_000_0023_01C5102F.4F5F7350 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Message ----- Original Message -----=20 From: Russell Duffy=20 To: Rotary motors in aircraft=20 Sent: Wednesday, February 09, 2005 10:55 AM Subject: [FlyRotary] Re: Microtech EFI and Tuning, was Re: [FlyRotary] = Re: Bad day at the airport I got up to 5100 rpms static, and most people told me that the prop = would most likely unload in flight. How can I obtain more than 5100 = rpm's unless I fly it? =20 Hi Paul, I asked Tracy that same question when I was first tuning my EC-2. The = answer (for his unit) was that it didn't matter. The system bases it's = fuel injection pulse width on MAP, which will be nearly the same in = static runs as it is in normal climb speeds. When your prop unloads in = flight, you run higher rpms, but that doesn't change the pulse width = requirement for each intake cycle at a given MAP. It just means you = need more pulses, because you have more intake cycles. =20 It's VERY important to realize that everything I just said was based = on Tracy's EC-2. There's a very real chance that the MicroTech DOES = care what the rpm is. I know that the Power FC computer in my FD had a = fuel injection and timing table that was based on RPM and MAP. This = gives you more power to tune, but as they say, with power comes = responsibility :-) FWIW, I really do like the MicroTech unit, and I thought really hard = about getting a couple for the single rotor project, but eventually went = with what I know, which is Tracy's EC-2. Part of that decision was = based on having a backup controller if I ever suspected a problem, = though it sure would be nice if someone would include the ability to = save and restore tuning parameters (between slathering foam and = fiberglass on a clapped out travel trailer) :-) I also like the = built in backup (which would have ruled out an EFI tuning issue for = you), and don't quite know how you'd wire two MicroTech's together. I = also like the mixture knob, which is powerful enough to overcome almost = any tuning mistake. I also felt it was safer for me to have only one = unit to try to remember. =20 Hang in there Paul. Give this some thorough consideration before = doing anything drastic. I seem to recall you giving me some similar = advice not long ago. =20 Cheers, Rusty =20 Hi, Rusty....stealing your red color....Yes, you program the MicroTech = unit according to rpm's. At every 500 rpm, you can set it up for that = rpm....ie...3000 rpm, 3500, 4000, 4500, etc. I had it set up for 5000, = but could not really properly set it up for 5500 or 6000 until I reach = that rpm and do the fine tuning. I just set the 5500 and 6000 the same = as the 5000 rpm settings, figuring that would be close enough to at = least continue running so that I could fine tune it in the air. I have not been able to get to the computer for a couple of = days, so I have 324 messages to look at, so if I say something in this = post that is out of date, I appologize.=20 I went to the airport yesterday and pulled the spark plugs and = inspected them. They looked brand new. No soot, no sign of overheating = or porcelain damgae. I fired the engine up and of course it ran like a fine swiss = watch. Good idle, good midrange, and 5300 rpm's static instead of the = usual 5200 rpm's. I have been doing a lot of thinking (dangerous = territory, I know) about my incident. I'm 99.95% sure it was vapor = lock/fuel delivery problems, not the MicroTech unit or it's settings. = On the day of the incident, I had run the engine up with the larger prop = until the temps got too hot. (pusher, no prop blast to help cool it), = then I immediately swapped props (installed the smaller prop to get more = rpm's), which only took about 10 minutes with my brother's help, then = fired it up, lined up on the runway and tried to do some more tuning for = max rpm's. Now, the temps were above 220 and climbing. I needed to get = it airborne ASAP, as my cooling system will cool the engine even in a = climb. Unfortunately, I suspect that by the time I rotated, the temps = were probably around 230 or 240, with the engine at WOT. Pretty good = scenario for hot cowling temps and vapor lock. The one thing that I failed to do, and probably should have = done was to turn on the aux fuel pump. I have a Facet fuel pump that = was originally intended to supply 6 psi to the sump tank. Never needed = it, but it certaintly wouldn't have hurt anything to turn it on. It = would only pressurize the sump tank, and that may or may not have had = any effect, as the sump tank is always full because it gets fuel from = both the tanks as well as the return fuel from the fuel pressure = regulator.=20 Looking at my fuel system closer led me to a couple of = observations/improvements that might solve the problem. Number one = would be to install firesleeve over the stainless steel braided fuel = supply line that goes from the fuel pumps to the fuel rail, as it is = close to the engine, and attached to the engine with adel clamps. Second might be to move the two high pressure fuel pumps to the = cold side of the firewall, or install a small duct to allow cooling air = to the pumps. In rethinking this, the duct would not supply any air = unless the plane was moving, and I believe the pumps get plenty of = moving air as is in flight. Third....avoid long max throttle runups just prior to takeoff. I = think this is the biggest "helpful hint" of all. Yesterday, when I ran = the engine up until the water temp hit 240, the surge tank overflow was = spitting out antifreeze about 3 feet. It just did it for a moment, then = I put a 100 volt fan under the NACA duct to supply cooling air. After = 10 minutes, the water temp still read 230, so I started the engine, and = as the water circulated at idle, the temps immediately came back down to = around 180. =20 Hope I didn't bore everyone to death with this long post. Just = trying to keep everyone informed. Paul Conner -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.8.6 - Release Date: 2/7/2005 ------=_NextPart_000_0023_01C5102F.4F5F7350 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Message
 
----- Original Message -----
From:=20 Russell=20 Duffy
Sent: Wednesday, February 09, = 2005 10:55=20 AM
Subject: [FlyRotary] Re: = Microtech EFI=20 and Tuning, was Re: [FlyRotary] Re: Bad day at the airport

I got up to 5100 rpms static, = and most=20 people told me that the prop would most likely unload in flight.  = How can=20 I obtain more than 5100 rpm's unless I fly it?   
 
 
Hi Paul,
 
I asked Tracy that same question when I was = first tuning=20 my EC-2.  The answer (for his unit) was that it didn't = matter.  The=20 system bases it's fuel injection pulse width on MAP, which will = be nearly=20 the same in static runs as it is in normal climb = speeds.  =20 When your prop unloads in flight, you run higher rpms, but that = doesn't change=20 the pulse width requirement for each intake cycle at a given = MAP.  It=20 just means you need more pulses, because you have more intake=20 cycles.  
 
It's VERY important to realize that = everything I just=20 said was based on Tracy's EC-2.  There's a very real chance that = the=20 MicroTech DOES care what the rpm is.  I know that the Power = FC=20 computer in my FD had a fuel injection and timing table that was based = on RPM=20 and MAP.  This gives you more power to tune, but as they say, = with power=20 comes responsibility :-)
 
FWIW, I really do like the MicroTech = unit, and I=20 thought really hard about getting a couple for the single rotor = project, but=20 eventually went with what I know, which is Tracy's EC-2.   = Part of=20 that decision was based on having a backup controller if I ever = suspected a=20 problem, though it sure would be nice if someone would include = the=20 ability to save and restore tuning parameters (between=20 slathering foam and fiberglass on a clapped out travel = trailer) =20 :-)    I also like the built in backup (which would = have ruled=20 out an EFI tuning issue for you), and don't quite know how you'd = wire two=20 MicroTech's together.   I also like the mixture knob, which = is=20 powerful enough to overcome almost any tuning mistake.  I also = felt it=20 was safer for me to have only one unit to try to = remember.   =20
 
Hang in there Paul.   Give this=20 some thorough consideration before doing anything drastic.  = I seem=20 to recall you giving me some similar advice not long=20 ago.  
 
Cheers,
Rusty  

Hi, Rusty....stealing your red = color....Yes, you program the MicroTech unit according to rpm's.  = At=20 every 500 rpm, you can set it up for that rpm....ie...3000 rpm, 3500, = 4000,=20 4500, etc.  I had it set up for 5000, but could not really = properly set=20 it up for 5500 or 6000 until I reach that rpm and do the fine tuning. = I just=20 set the 5500 and 6000 the same as the 5000 rpm settings, figuring that = would=20 be close enough to at least continue running so that I could fine tune = it in=20 the air.
      = I have not=20 been able to get to the computer for a couple of days, so I have 324 = messages=20 to look at, so if I say something in this post that is out of date, I=20 appologize.
     I = went to the=20 airport yesterday and pulled the spark plugs and inspected them. They = looked=20 brand new. No soot, no sign of overheating or porcelain = damgae.
    I fired the = engine up=20 and of course it ran like a fine swiss watch. Good idle, good = midrange, and=20 5300 rpm's static instead of the usual 5200 rpm's.   I have = been=20 doing a lot of thinking (dangerous territory, I know) about my = incident. =20 I'm 99.95% sure it was vapor lock/fuel delivery problems, not the = MicroTech=20 unit or it's settings.  On the day of the incident, I had run the = engine=20 up with the larger prop until the temps got too hot. (pusher, no prop = blast to=20 help cool it), then I immediately swapped props (installed the smaller = prop to=20 get more rpm's), which only took about 10 minutes with my brother's = help, then=20 fired it up, lined up on the runway and tried to do some more tuning = for max=20 rpm's.  Now, the temps were above 220 and climbing.  I = needed to get=20 it airborne ASAP, as my cooling system will cool the engine even in a=20 climb.  Unfortunately, I suspect that by the time I rotated, the = temps=20 were probably around 230 or 240, with the engine at WOT.  Pretty = good=20 scenario for hot cowling temps and vapor lock.
       The=20 one thing that I failed to do, and probably should have done was to = turn on=20 the aux fuel pump.  I have a Facet fuel pump that was originally = intended=20 to supply 6 psi to the sump tank.  Never needed it, but it = certaintly=20 wouldn't have hurt anything to turn it on. It would only pressurize = the sump=20 tank, and that may or may not have had any effect, as the sump tank is = always=20 full because it gets fuel from both the tanks as well as the return = fuel from=20 the fuel pressure regulator.
      = Looking at=20 my fuel system closer led me to a couple of observations/improvements = that=20 might solve the problem.  Number one would be to install = firesleeve over=20 the stainless steel braided fuel supply line that goes from the fuel = pumps to=20 the fuel rail, as it is close to the engine, and attached to the = engine with=20 adel clamps.
     = Second might be=20 to move the two high pressure fuel pumps to the cold side of the = firewall, or=20 install a small duct to allow cooling air to the pumps.  In = rethinking=20 this, the duct would not supply any air unless the plane was moving, = and I=20 believe the pumps get plenty of moving air as is in = flight.
     = Third....avoid=20 long max throttle runups just prior to takeoff. I think this is the = biggest=20 "helpful hint" of all.  Yesterday, when I ran the engine up = until=20 the water temp hit 240, the surge tank overflow was spitting out = antifreeze=20 about 3 feet. It just did it for a moment, then  I put a 100 volt = fan=20 under the NACA duct to supply cooling air.  After 10 minutes, the = water=20 temp still read 230, so I started the engine, and as the water = circulated at=20 idle, the temps immediately came back down to around 180.  =
     Hope = I didn't=20 bore everyone to death with this long post.  Just trying to keep = everyone=20 informed.  Paul Conner

No virus found in this incoming message.
Checked by AVG=20 Anti-Virus.
Version: 7.0.300 / Virus Database: 265.8.6 - Release = Date:=20 2/7/2005
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