X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao101.cox.net ([68.230.241.45] verified) by logan.com (CommuniGate Pro SMTP 5.3.5) with ESMTP id 4217211 for flyrotary@lancaironline.net; Sat, 10 Apr 2010 22:47:18 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.45; envelope-from=rv-4mike@cox.net Received: from fed1rmimpo01.cox.net ([70.169.32.71]) by fed1rmmtao101.cox.net (InterMail vM.8.00.01.00 201-2244-105-20090324) with ESMTP id <20100411024640.GVVO2579.fed1rmmtao101.cox.net@fed1rmimpo01.cox.net> for ; Sat, 10 Apr 2010 22:46:40 -0400 Received: from willsPC ([174.66.169.142]) by fed1rmimpo01.cox.net with bizsmtp id 42mg1e00134gpFS032mglW; Sat, 10 Apr 2010 22:46:40 -0400 X-VR-Score: -30.00 X-Authority-Analysis: v=1.1 cv=3rYd4LfcKLU522ZHXfO06E856SAcXud2pffNCWjpFlA= c=1 sm=1 a=s-76OcHdJycA:10 a=cPUexvdKvEVW1PN6gG+JiA==:17 a=1bAtt8XEktsfOAWTjlkA:9 a=OHcs-7h3Pvv96ZZgZNkuQ8bQ7DwA:4 a=wPNLvfGTeEIA:10 a=UretUmmEAAAA:8 a=Ia-xEzejAAAA:8 a=-V2tdp6T57Zhm0JDrAYA:9 a=ULFxew-4nkrWmTECRQEA:7 a=pWywe1WpSvh7mZtVyQ_mU817A6kA:4 a=iVkDmfvjeKcA:10 a=EzXvWhQp4_cA:10 a=cPUexvdKvEVW1PN6gG+JiA==:117 X-CM-Score: 0.00 Message-ID: <38C4B6DE03EE4508B83B63848E5516AC@willsPC> From: "Mike Wills" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Fuel Pressure sensor warning / crank sensor mounts Date: Sat, 10 Apr 2010 19:46:42 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0068_01CAD8E6.8B85CD40" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8089.726 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8089.726 This is a multi-part message in MIME format. ------=_NextPart_000_0068_01CAD8E6.8B85CD40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I had an isolator made by Autometer but was never able to completely = purge the air and get reliable readings. After multiple attempts I = finally gave up and deleted it. So I guess I may be on borrowed time = before I get the fuel leak. My history seems to be that if it can fail = on my airplane it will. If you identify something that works and is = relatively small and inexpensive please let us know. Mike Wills From: Tracy Crook=20 Sent: Saturday, April 10, 2010 2:34 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Fuel Pressure sensor warning / crank sensor = mounts Just got done doing a final flight test on the RV-8 before Sun n Fun = decision time. The battery had gone flat from being discharged to zero = too many times by the Blue Mountain EFIS. It draws some power even when = off. Replaced the battery yesterday with another Odessy 925 and the = engine turned over smartly. Had just changed out the EC2 for an EC3 just because i felt the need to = say I had personally flown it on a 20B. =20 Also made a new mount for the RX-8 crank sensor. I had been getting an = occasional high speed miss above 6200 rpm and suspected the problem = might be the same as a customer's Continental AC engine that was = equipped with an EC3. That turned out to be a resonant condition where = the mount would vibrate above a certain rpm causing the distance between = sensor and trigger wheel to vary enough to cause distortion of the = signal. That caused the EC3 to lose sync momentarily. Making a very = rigid mount cured the problem on the Cont. and my 20B. It's sweet at = all rpms now. This might have been the problem on Mark Steitle's 20B as = well. We thought it was the material it was made of but i'm not sure = about that now. He also replaced his mount and the problem went away. = Anyway, if you make your own crank sensor mount, make sure it is really = rigid. The RV-8 flew perfectly on the test flight with only engine anomaly = being a low fuel pressure reading. I knew it was an instrument problem = because the engine wouldn't run if the fuel pressure was only 6 psi. = Un-cowled the engine and heard a hissing noise coming from the fuel = pressure sensor. There was a steady drip of fuel from the terminal end = of the sensor. Why i didn't have an engine fire in flight I don't know. = SO, I can no longer recommend using the VDO pressure sensors for use = on fuel systems. Either an isolator must be used or a sensor rated for = fuel exposure be installed. I've been using one on my -4 for >7 years = with no problems. About 3 years ago VDO started putting a sticker in = the pressure sensor package saying not to use them on fuel pressure = applications. I suspect they changed something in the manufacturing = process. I'll do some research on sensors and see if I can find a = suitable replacement that doesn't cost a fortune. Anyone have a lead = on sensor isolators? My transponder also decided it wasn't going to work this time. I = recently had the instrument panel out for the EC3 change so I think it's = an antenna connector or coax problem. Bummer. Too many last minute squawks to fix in time so will have to = take the RV-4 to SnF :-(=20 Tracy ------=_NextPart_000_0068_01CAD8E6.8B85CD40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I had an isolator made by Autometer but was = never able=20 to completely purge the air and get reliable readings. After multiple = attempts I=20 finally gave up and deleted it. So I guess I may be on borrowed time = before I=20 get the fuel leak. My history seems to be that if it can fail on my = airplane it=20 will.  If you identify something that works and is relatively small = and=20 inexpensive please let us know.
 
Mike Wills

Sent: Saturday, April 10, 2010 2:34 PM
Subject: [FlyRotary] Re: Fuel Pressure sensor warning / = crank sensor=20 mounts


Just got done doing a final flight test on the RV-8 = before=20 Sun n Fun decision time.  The battery had gone flat from being = discharged=20 to zero too many times by the Blue Mountain EFIS.  It draws some = power even=20 when off.  Replaced the battery yesterday with another Odessy 925 = and the=20 engine turned over smartly.

 Had just changed out the EC2 = for an EC3=20 just because i felt the need to say I had personally flown it on a = 20B. =20

 Also made a new mount for the RX-8 crank sensor.  I = had been=20 getting an occasional  high speed miss above 6200 rpm and suspected = the=20 problem might be the same as a customer's Continental AC engine that was = equipped with an EC3.  That turned out to be a resonant condition = where the=20 mount would vibrate above a certain rpm causing the distance between = sensor and=20 trigger wheel to vary enough to cause distortion of the signal.  = That=20 caused the EC3 to lose sync momentarily.  Making a very rigid mount = cured=20 the problem on the Cont. and my 20B.  It's sweet at all rpms = now. =20 This might have been the problem on Mark Steitle's 20B as well.  We = thought=20 it was the material it was made of but i'm not sure about that = now.  He=20 also replaced his mount and the problem went away.  Anyway, if you = make=20 your own crank sensor mount, make sure it is really rigid.

The = RV-8 flew=20 perfectly on the test flight with only engine anomaly being a low fuel = pressure=20 reading.  I knew it was an instrument problem because the engine = wouldn't=20 run if the fuel pressure was only 6 psi.  Un-cowled the engine and = heard a=20 hissing noise coming from the fuel pressure sensor.  There was a = steady=20 drip of  fuel from the terminal end of the sensor.  Why i = didn't have=20 an engine fire in flight I don't know.  SO,  I can no = longer=20 recommend using the VDO pressure sensors for use on fuel = systems. =20 Either an isolator must be used or a sensor rated for fuel exposure be=20 installed.  I've been using one on my -4 for >7 years with no = problems.=20   About 3 years ago VDO started putting a sticker in the pressure = sensor=20 package saying not to use them on fuel pressure applications.   I = suspect=20 they changed something in the manufacturing process.  I'll do some = research=20 on sensors and see if I can find a suitable replacement that doesn't = cost a=20 fortune.   Anyone have a lead on sensor isolators?

My=20 transponder also decided it wasn't going to work this time.  I = recently had=20 the instrument panel out for the EC3 change so I think it's an antenna = connector=20 or coax problem.

Bummer.  Too many last minute squawks to = fix in=20 time so will have to take the RV-4 to SnF :-(

Tracy
------=_NextPart_000_0068_01CAD8E6.8B85CD40--