Return-Path: Received: from fed1rmmtao10.cox.net ([68.230.241.29] verified) by logan.com (CommuniGate Pro SMTP 4.2) with ESMTP id 381180 for flyrotary@lancaironline.net; Fri, 27 Aug 2004 13:50:45 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.29; envelope-from=ALVentures@cox.net Received: from BigAl ([68.107.116.221]) by fed1rmmtao10.cox.net (InterMail vM.6.01.03.02.01 201-2131-111-104-103-20040709) with ESMTP id <20040827174959.QLLG11367.fed1rmmtao10.cox.net@BigAl> for ; Fri, 27 Aug 2004 13:49:59 -0400 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Engine run Date: Fri, 27 Aug 2004 10:50:07 -0700 Message-ID: <000001c48c5e$4a9aa600$6400a8c0@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C48C23.9E3BCE00" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C48C23.9E3BCE00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Yeah; I=92m sure my experience isn=92t much different than others on the = first runs. I guess I had higher expectations since I=92ve run on the dyno, = and had things pretty well dialed in. The other is that; except where I was = using different sensors, I expected to have hard data from the EM2, and it = seems there are enough surprises that it cast a shadow on much of the data. = Makes for some anxiety. =20 First fuel pressure is key. You want it lower. I have the same TWM = fuel pressure regulator that you do. Make sure that it is hooked up to the manifold. You should be seeing pressures closer to 32psi at idle. I = opened up the tension screw on the pressure regulator all the way. That gives = me about 41 PSI with the engine off, up near 50 when running boost, and 32 = at idle. Any test I made with higher fuel pressures made the situation = much worse. =20 =20 I understand that the EM2 is preset for a VDO 0-100 fuel pressure = sender. Mine is a 0 -80, so I adjusted the scale factor from 10.23 to 12.8, and = the low level offset just a bit to get 0 at zero pressure. But is the = reading now correct? I guess I=92ll believe it when I have another gauge to = verify it. =20 Try different configurations with the manifold pressure lines. Make = SURE that each line is connected to all the runners/rotors. In my set up controller A samples both rotors right at the port, while controller B samples the pressure (from both runners T'd) just downstream of the = throttle body. I find that A runs a little better on the ground and B seem to be = a little smoother at altitude (though both work very well above 2000 RPM. = =20 The TWM MAP port is connected to two of the three barrels (one per = rotor) so it is averaging rotors 2 & 3. Worked fine in the dyno runs. I added a = port at the rotor 1 intake, which I=92m using for the controller B and the = fuel pressure regulator. =20 Keep playing with the MAP and work very hard to make sure there are no = gaps. Use a wide Mode 2 band at first, then fine tune with a narrow one. =20 I had the mixture correction table mapped out pretty well on the dyno, except at very low MAP, I think around 12-13 is as low as we saw on the dyno. Two things have changed since then =96 the pressure regulator I = had then was not MAP referenced (fixed at 40 psi); and, when I sent the EC2 = back to Tracy for updating earlier this year, he made some adjustment (I know = not what) to compensate for the two injector sizes that I have (570 cc.min primaries and 500 secondary). I intended to star over with the default, = but following the directions to reset did not change the correction values. = I then decided it best to work off the mixture mapping I had done. I have made no attempt to change the mixture table yet, and viewing it on the = EM2 it seems OK. I adjusted the mixture with the EC2 mixture knob at 2000 = rpm from about 10:00 oclock (rough - too lean) to 5:00 (rough - too rich), = and it was smoothest at about 2:00, but still rough. =20 I finally got my to idle pretty good down to about 1200 or 1300 = (sometimes 1000). It actually seems to run a little better when cold. Sometimes = it runs exceedingly well and sounds like music. Sometimes not. But if it = runs rough all I have to do lately is get it back above 1600 and it settles = down. =20 Keep at it. If you want I will be working on mine all weekend and you = can come down to MYF and hear it idle if interested. =20 Did I know you were at Montgomery? I thought you were somewhere up = around LA. I might like to get down there and chat, but don=92t know when = right now. Maybe you could send me a number where I can get in touch. = Alg3@cox.net. =20 Thanks, =20 Al =20 Dave Leonard >=20 > I guess I have now done what I=92d consider the first serious runs of = the > engine on the plane, and I have so many question marks in my head, = it=92s hard > to know what to address next. >=20 > The biggest issue is; I cannot get smooth running up to about 2200 = rpm; > which is as far as I went. At about 2000 I adjusted mixture from too = lean > to too rich, and nowhere does it smooth out completely =96 some = roughness, > mild surging. At lower rpm, 1000 =96 1500 it is quite rough and = unsteady, > which is disconcerting in itself, but worrisome when it goes through periods > of torsional vibration with the reduction gear backlash, which is = noisy and > shakes the plane. >=20 > Of course it brings back the recent discussions of you other guys with = the > 550 injectors in the primary. I kind of glossed over that because I > recalled smooth running on the dyno. In hindsight now, I think the operator > figured out early-on that to keep it smooth he needed to keep some = load on =96 > just turn the load knob a little and it was fine. And on the dyno = when it > wasn=92t running smooth, no big deal =96 no redrive to backlash, and = the engine > is bolted down in the next room. You could just hear that it wasn=92t running > smooth. >=20 > Still, I suspect something is different now; and perhaps you=92ll = indulge my > dumping, and pass on a clue or two. >=20 > At 2000 I=92m seeing a 13.1 MAP reading. Seems low to me. Is it? = That puts > it below the stage point, yet when I turned off the primary injectors, = it > continued to run; just rougher. Same effect turning off the = secondaries. > Hotest EGT was at about 1100, lowest about 980. Bigger spread than I = ever > saw on the dyno runs, but the data we took there was always under = higher > load. >=20 > Fuel pressure reads 50 psi, TWM tells me it came to me preset at 43.5. When > the coolant temp read 125 when the pipes and rad tanks were just about = too > hot to touch, which I guessed to be more like 140. I=92m suspicious = of just > about every readout. Later when the WT read 140, the CHT TC that = measure > temps in and out of the rads were reading about 85. I believed backup > gauges were unnecessary. >=20 > Oh yeah; the mixture bar reads just about full scale all the time, = even when > the engine is about to die from being too lean. I have a different = heated > Bosch sensor, which I assumed would have the same 0-1volt range. = Maybe not. > Is the sensor output voltage low when lean or rich? With the engine = off and > sensor heated I measured .052 volts. I tried to get a reading with = the > engine running, but all I got was about .025 and I can=92t be certain = I had > contact with the lead =96 and with the prop spinning so close by I = didn=92t > spend too much time trying. >=20 > One other major concern. With hot oil (150) at the filter block where = the > feed goes to the redrive, the =BC=94 Al line to the redrive was hardly = above > ambient temp a minute or two after shutdown; suggesting little or no = flow > was going there. Oil pressure was in the 90=92s. I=92m not aware = that there is > an orifice in there. This has me a bit baffled. >=20 > Oil pressure, coolant pressure, Oil temp seem fine. >=20 > Maybe I should go to a movie. >=20 > Al (not ecstatic) >=20 > =20 >=20 >=20 >=20 =20 =20 >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_0001_01C48C23.9E3BCE00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Yeah; = I’m sure my experience isn’t much different than others on the first runs.=A0 = I guess I had higher expectations since I’ve run on the dyno, and had things = pretty well dialed in.=A0 The other is that; except where I was using different = sensors, I expected to have hard data from the EM2, and it seems there are enough surprises that it cast a shadow on much of the data.=A0 Makes for some = anxiety.

 

First fuel pressure is key.=A0 You want it lower.=A0 I have the same TWM fuel = pressure regulator that you do.=A0 Make sure that it is hooked up to the = manifold.=A0 You should be seeing pressures closer to 32psi at idle.=A0 I opened up the = tension screw on the pressure regulator all the way.=A0 That gives me about 41 = PSI with the engine off, up near 50 when running boost, and 32 at idle.=A0 Any = test I made with higher fuel pressures made the situation much = worse.

 

 

I understand = that the EM2 is preset for a VDO 0-100 fuel pressure sender.=A0 Mine is a 0 -80, = so I adjusted the scale factor from 10.23 to 12.8, and the low level offset = just a bit to get 0 at zero pressure. =A0But is the reading now correct?=A0 I = guess I’ll believe it when I have another gauge to verify it.

 

Try different configurations with the manifold pressure lines.=A0 Make SURE = that each=A0 line is connected to all the runners/rotors.=A0 In my set up controller = A samples both rotors right at the port, while controller B samples the pressure = (from both runners T'd) just downstream of the throttle body.=A0 I find that A = runs a little better on the ground and B seem to be a little smoother at = altitude (though both work very well above 2000 RPM.=A0

 

The TWM MAP = port is connected to two of the three barrels (one per rotor) so it is averaging = rotors 2 & 3. Worked fine in the dyno runs. =A0I added a port at the rotor = 1 intake, which I’m using for the controller B and the fuel pressure = regulator.

 

Keep playing with the MAP and work very hard to make sure there are no = gaps.=A0 Use a wide Mode 2 band at first, then fine tune with a narrow = one.

 

I had the = mixture correction table mapped out pretty well on the dyno, except at very low = MAP, I think around 12-13 is as low as we saw on the dyno. =A0Two things have = changed since then – the pressure regulator I had then was not MAP = referenced (fixed at 40 psi); and, when I sent the EC2 back to Tracy for updating = earlier this year, he made some adjustment (I know not what) to compensate for = the two injector sizes that I have (570 cc.min primaries and 500 secondary).=A0 = I intended to star over with the default, but following the directions to = reset did not change the correction values. =A0I then decided it best to work = off the mixture mapping I had done.=A0 I have made no attempt to change the = mixture table yet, and viewing it on the EM2 it seems OK. =A0I adjusted the mixture = with the EC2 mixture knob at 2000 rpm from about 10:00 oclock (rough - too lean) to 5:00 (rough - = too rich), and it was smoothest at about 2:00, but = still rough.

 

I finally got my to idle pretty good down to about 1200 or 1300 (sometimes 1000).=A0 It actually seems to run a little better when cold.=A0 = Sometimes it runs exceedingly well and sounds like music.=A0 Sometimes not. =A0But if it = runs rough all I have to do lately is get it back above 1600 and it settles = down.

 

Keep at it.=A0 If you want I will = be working on mine all weekend and you can come down to MYF and hear it idle if interested.

 

Did I know you = were at Montgomery?=A0 I thought you were somewhere up around LA.=A0 I might like to get down = there and chat, but don’t know when right now.=A0 Maybe you could send me a = number where I can get in touch. =A0Alg3@cox.net.

 

Thanks,<= /font>

 

Al

 

Dave Leonard

>

> I guess I have now done what I’d consider the first serious runs = of the

> engine on the plane, and I have so many question marks in my head, = it’s hard

> to know what to address next.

>

> The biggest issue is; I cannot get smooth running up to about 2200 = rpm;

> which is as far as I went.=A0 At about 2000 I adjusted mixture from too = lean

> to too rich, and nowhere does it smooth out completely – some = roughness,

> mild surging.=A0 At lower rpm, 1000 – 1500 it is quite rough and = unsteady,

> which is disconcerting in itself, but worrisome when it goes through = periods

> of torsional vibration with the reduction gear backlash, which is noisy = and

> shakes the plane.

>

> Of course it brings back the recent discussions of you other guys with = the

> 550 injectors in the primary.=A0 I kind of glossed over that because = I

> recalled smooth running on the dyno.=A0 In hindsight now, I think the = operator

> figured out early-on that to keep it smooth he needed to keep some load = on –

> just turn the load knob a little and it was fine.=A0 And on the dyno = when it

> wasn’t running smooth, no big deal – no redrive to backlash, = and the engine

> is bolted down in the next room.=A0 You could just hear that it = wasn’t running

> smooth.

>

> Still, I suspect something is different now; and perhaps you’ll = indulge my

> dumping, and pass on a clue or two.

>

> At 2000 I’m seeing a 13.1 MAP reading.=A0 Seems low to me.=A0 Is = it? That puts

> it below the stage point, yet when I turned off the primary injectors, = it

> continued to run; just rougher.=A0 Same effect turning off the = secondaries.

> Hotest EGT was at about 1100, lowest about 980.=A0 Bigger spread than I = ever

> saw on the dyno runs, but the data we took there was always under = higher

> load.

>

> Fuel pressure reads 50 psi, TWM tells me it came to me preset at = 43.5.=A0 When

> the coolant temp read 125 when the pipes and rad tanks were just about = too

> hot to touch, which I guessed to be more like 140.=A0 I’m = suspicious of just

> about every readout. Later when the WT read 140, the CHT TC that = measure

> temps in and out of the rads were reading about 85.=A0 I believed = backup

> gauges were unnecessary.

>

> Oh yeah; the mixture bar reads just about full scale all the time, even = when

> the engine is about to die from being too lean.=A0 I have a different = heated

> Bosch sensor, which I assumed would have the same 0-1volt range.=A0 = Maybe not.

> Is the sensor output voltage low when lean or rich?=A0 With the engine = off and

> sensor heated I measured .052 volts.=A0 I tried to get a reading with = the

> engine running, but all I got was about .025 and I can’t be = certain I had

> contact with the lead – and with the prop spinning so close by I didn’t

> spend too much time trying.

>

> One other major concern.=A0 With hot oil (150) at the filter block where = the

> feed goes to the redrive, the =BC” Al line to the redrive was = hardly above

> ambient temp a minute or two after shutdown; suggesting little or no = flow

> was going there.=A0 Oil pressure was in the 90’s.=A0 I’m not = aware that there is

> an orifice in there.=A0 This has me a bit baffled.

>

> Oil pressure, coolant pressure, Oil temp seem fine.

>

> Maybe I should go to a movie.

>

> Al (not ecstatic)

>

>=A0

>

>

>

 

 

>>=A0 Homepage:=A0 http://www.flyrotary.com/

>>=A0 Archive:=A0=A0 = http://lancaironline.net/lists/flyrotary/List.html

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