Return-Path: Received: from [24.25.9.102] (HELO ms-smtp-03-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 3050868 for flyrotary@lancaironline.net; Sun, 29 Feb 2004 08:01:32 -0500 Received: from edward (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-03-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i1TD1Ts2024016 for ; Sun, 29 Feb 2004 08:01:30 -0500 (EST) Message-ID: <007601c3fec4$2a6edea0$2402a8c0@edward> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: 13B - No start problem Date: Sun, 29 Feb 2004 08:01:37 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0073_01C3FE9A.415D5440" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0073_01C3FE9A.415D5440 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageDavid, sounds like you on the trail of the problem, HOWEVER, I = would not stop yet. Here's my view of the problem. Yes, the EC2 will = draw some current if the power to the injectors are on, but it should be = on the order of milliamps. If you are using the Peak and Hold (low = impedance) injectors they require around 4 amps to unseat the pentle and = inject fuel. The high impedance injectors require around 2 amps. The = EC2 power requirements with the engine off is minimal - in the milliamp = range. I could be wrong, but to the best of my knowledge, the EC2 = should not be drawing enough current to unseat the injectors unless the = engine is running. Your diagnoses appears reasonable except the EC2 just does not normally = draw anywhere near sufficient current to unseat the injectors. I can = turn my injectors on - leaving the EC2 switch off - there is an initial = squirt of fuel due to the transit phenomena I mentioned, but after that = the injectors stay seated. Yes, the EC2 program light is on showing the = EC2 is drawing power through the injector power circuit the same as = yours. =20 However, your finding sounds significant. I would not hesitate to query = Tracy about what you have found, it does not sound normal to me. Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Sunday, February 29, 2004 2:59 AM Subject: [FlyRotary] Re: 13B - No start problem Ed & Rusty, thanks again for your replies. Today I went out to the = hangar and solved the issue, . it's very strange. I started by = applying an ohm meter across the injector leads with the fuses removed. = As we would expect from my problem one lead (hot lead) would indicate no = connection with ground while the other showed some current flow, but not = zero resistance with ground, 1.2 Kohms (or 0.2 Kohms if I reversed the = polarity of the ohmmeter).. (scratch head and look dumbfounded). The = same with the other injectors. Hmmmm. On a hunch I went and turned on the main power to the EC2 and re-tried = the above experiment. Low and behold, there was no longer any current = to ground. (infinite resistance both leads). The system would hold fuel = pressure and all was right in my little world. In other words, if there = is power to only the injectors the EC2 seems to need some current and = will draw across the injectors causing them to open. But if I applied = power to the main EC2 power input, the EC2 had enough power to properly = close the injector circuits. I repeated the entire experiment to make = sure I wasn't seeing things. Now that I know how things work, it wont be a problem.. But still I = haven't run the engine. J (i.e. and sure to be in dire straits again = soon) Thanks again for your help. David Leonard The Rotary Roster: http://members.aol.com/_ht_a/rotaryroster/index.html I am also having trouble picturing where I could have gone wrong in = the wiring. It seems unlikely to me that I could have grounded all 4 of = the injector leads. Your idea about testing with the main connector = unplugged is a good place to start. But assuming that checks out OK (no = ground with the connector unplugged), I really would have no idea what = to do next. I can't believe that I would put all 4 injector leads in = the wrong hole. BTW, I did not install an injector disable switch. Hi David, Ed's message is great, and I won't try to add much to it. =20 I did just take a look at the EC-2 plug again, and noticed that the = primary injector wires are pins 17 and 18, with a ground on 19. The = secondary wires are pins 35 and 36, with the ground on 37. These are = supposed to be larger wire than the rest, so they don't fit as well in = the plug. All it would take is a strand of wire between 18 and 19, or = between 36 and 37 to cause one injector to open up when you apply power. = I'm betting you'll find your problem in the connector. Of course it = also wouldn't be too hard to accidentally swap one of the injector wires = with one of the grounds, which might do it too. Naturally, I would = never make such a mistake (ahem...) :-) Good luck, Rusty (off to TIG some stainless)=20 ------=_NextPart_000_0073_01C3FE9A.415D5440 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
David, sounds like you on the trail of = the problem,=20 HOWEVER, I would not stop yet.  Here's my view of the = problem.  Yes,=20 the EC2 will draw some current if the power to the injectors are on, but = it=20 should be on the order of milliamps.  If you are using the Peak and = Hold=20 (low impedance) injectors they require around 4 amps to unseat the = pentle and=20 inject fuel. The high impedance injectors require around 2 = amps.  The=20 EC2 power requirements with the engine off is minimal - in the milliamp=20 range.  I could be wrong, but to the best of my = knowledge,=20  the EC2 should not be drawing enough current to unseat the = injectors=20 unless the engine is running.
 
Your diagnoses appears reasonable = except the EC2=20 just does not normally draw anywhere near sufficient current to = unseat=20 the injectors.  I can turn my injectors on - leaving the EC2 switch = off -=20 there is an initial squirt of fuel due to the transit phenomena I = mentioned, but=20 after that the injectors stay seated.  Yes, the EC2 program light = is on=20 showing the EC2 is drawing power through the injector power circuit the = same as=20 yours. 
 
However, your finding sounds = significant.  I=20 would not hesitate to query Tracy about what you have found, it does not = sound=20 normal to me.
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From:=20 David=20 Leonard
Sent: Sunday, February 29, 2004 = 2:59=20 AM
Subject: [FlyRotary] Re: 13B - = No start=20 problem

Ed & = Rusty, =20 thanks again for your replies.  Today I went out to the hangar = and solved=20 the issue, =85 it=92s very strange.   I started by applying = an ohm meter=20 across the injector leads with the fuses removed.  As we would = expect=20 from my problem one lead (hot lead) would indicate no connection with = ground=20 while the other showed some current flow, but not zero resistance with = ground,=20 1.2  Kohms (or 0.2 Kohms if I reversed the polarity of the = ohmmeter)=85.=20 (scratch head and look dumbfounded).  The same with the other=20 injectors.  Hmmmm.

 

On a hunch = I went and=20 turned on the main power to the EC2 and re-tried the above = experiment. =20 Low and behold, there was no longer any current to ground. (infinite=20 resistance both leads).  The system would hold fuel pressure and = all was=20 right in my little world.  In other words, if there is power to = only the=20 injectors the EC2 seems to need some current and will draw across the=20 injectors causing them to open.  But if I applied power to the = main EC2=20 power input, the EC2 had enough power to properly close the injector=20 circuits.  I repeated the entire experiment to make sure I = wasn=92t seeing=20 things.

 

Now that I = know how=20 things work, it wont be a problem=85.  But still I haven=92t run = the=20 engine=85  J  = (i.e. and sure=20 to be in dire straits again soon)

 

Thanks = again for your=20 help.

 

David=20 Leonard

The Rotary=20 Roster:

http://memb= ers.aol.com/_ht_a/rotaryroster/index.html

 

I am also = having=20 trouble picturing where I could have gone wrong in the wiring.  = It seems=20 unlikely to me that I could have grounded all 4 of the injector = leads. =20 Your idea about testing with the main connector unplugged is a good = place to=20 start.  But assuming that checks out OK (no ground with the = connector=20 unplugged), I really would have no idea what to do next.  I = can=92t believe=20 that I would put all 4 injector leads in the wrong hole.  BTW, I = did not=20 install an injector disable switch.

 

 

Hi=20 David,

 

Ed's = message is=20 great, and I won't try to add much to it.  =

 

I did just = take a=20 look at the EC-2 plug again, and noticed that the primary = injector wires=20 are pins 17 and 18, with a ground on 19.   The=20 secondary wires are pins 35 and 36, with the ground on 37.  These = are=20 supposed to be larger wire than the rest, so they don't fit as well in = the=20 plug.  All it would take is a strand of wire between 18 and 19, = or=20 between 36 and 37 to cause one injector to open up when you apply = power. =20 I'm betting you'll find your problem in the = connector.   =20 Of course it also wouldn't be too hard to accidentally swap = one of=20 the injector wires with one of the grounds, which might do it = too. =20 Naturally, I would never make such a mistake (ahem...) =20 :-)

 

Good=20 luck,

Rusty (off = to TIG=20 some stainless) 

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