X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-04.southeast.rr.com ([24.25.9.103] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1125024 for flyrotary@lancaironline.net; Tue, 23 May 2006 13:36:36 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-111-186.carolina.res.rr.com [24.74.111.186]) by ms-smtp-04.southeast.rr.com (8.13.6/8.13.6) with SMTP id k4NHZeYx006266 for ; Tue, 23 May 2006 13:35:41 -0400 (EDT) Message-ID: <001501c67e8f$687bba40$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Another case of heat-soaked coils? Date: Tue, 23 May 2006 13:36:21 -0400 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="utf-8"; reply-type=original Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Virus-Scanned: Symantec AntiVirus Scan Engine Tracy, lost two LS1 coils believed due to over heating. He now has air flow to his 4 LS` coils (also sitting on top of the engine). I suspect the Mazda coils may take more heat than the LS1 coils, I have not lost one to heat (yet) - but that is just speculation on my part. Ed ----- Original Message ----- From: To: "Rotary motors in aircraft" Sent: Tuesday, May 23, 2006 1:30 PM Subject: [FlyRotary] Re: Another case of heat-soaked coils? > Heat soak of the coils is hard to believe. In the 3rd gen turbo cars the > coils sit on top of the engine between the engine and the intake manifold, > and they get mighty hot and hardly ever stop working, in traffic at +100F, > with ac on, stop and go.....? > Marc > > ---- Kelly Troyer wrote: >> And the people said "Amen" !! >> -- >> Kelly Troyer >> Dyke Delta/13B/RD1C/EC2 >> >> >> >> >> >> >> -------------- Original message from "Tracy Crook" >> : -------------- >> >> >> Right-O on the difficulty of long distance diagnosis. >> >> John did tell me that the threshold of 'splutter' was around 38" Hg MAP. >> Since the engine quickly went down hill even at lower throttle settings >> and he thought it was only running on one rotor at the end of testing, I >> suspect there are a lot of clues to what is wrong other than the >> 'splutter' at 38". We just don't know what they are. The coils being >> bad is a long shot since it would mean that two of them died at once, not >> likely but possible. >> >> Sermon follows: >> >> Guys, Learn to be very sensitive to your engine. Know every nuance of >> its character. If you don't know what the air drifting out of the inlets >> after shutdown smells like, you aren't paying enough attention. >> >> Tracy >> ----- Original Message ----- >> From: Ed Anderson >> To: Rotary motors in aircraft >> Sent: Tuesday, May 23, 2006 7:45 AM >> Subject: [FlyRotary] Re: Another case of heat-soaked coils? >> >> >> John, Not being there makes it hard to make an assessment. Anytime I >> have >> had an engine spitting and popping it either mean the air/fuel mixture >> was >> too lean or I had a ignition problem (mainly timing). I have no >> experience >> with any coils other than the stock Mazda but additional cooling >> certainly >> could not hurt. It really sounds like to me your engine is increasing >> rpm >> until its getting into a region where the air/fuel mixture may be too >> lean. >> Normally a too lean engine will pop and spit but not certain if your >> sputter >> is same as my sputter {:>). Also you did not mention what boost levels >> you >> were running when this was happening. >> >> Ed >> >> >> >> Any time my engine acts abnormal, its grounded until I figure out the >> problem >> ----- Original Message ----- >> From: "John Slade" >> To: "Rotary motors in aircraft" >> Sent: Monday, May 22, 2006 9:56 PM >> Subject: [FlyRotary] Another case of heat-soaked coils? >> >> >> > Yesterday I took a friend for a ride and the engine purred sweetly for >> > the >> > entire trip. Looking back, the only thing different was that there >> > didn't >> > seem to be an rpm drop when I disabled leading or trailing coils during >> > the runup. >> > >> > Today all was normal during runup (except perhaps the coil disable >> > causing >> > no rpm drop) and full power got me 5300 before I couldn't hold it any >> > more >> > on the brakes. Take-off and climb were normal. On the downwind I was >> > showing 5800 rpm so I decide to coursen the prop. When I did I felt a >> > splutter. I reduced throttle and the engine ran normally. I increased >> > throttle. More splutter. I reduced throttle and it ran normally at >> > 4600. >> > Any more throttle and all I got was reduced power & popping and >> > spitting. >> > I circled the field trying mixture adjustments, checking fuel pressure >> > on >> > both pumps, coil & injector defeat and swapping to B computer. Nothing >> > seemed to make any difference, so I landed. >> > >> > The only change since the previous flight was that I'd replaced the >> > plugs >> > with a clean set - not new - just clean. Suspecting a bad plug I let >> > the >> > engine cool down a bit, then installed new ones. Later in the day the >> > engine ran fine during taxi and again reached 5300 on runup. >> > Acceleration >> > seemed normal then, halfway through the takeoff roll, I felt a >> > splutter, >> > so I aborted and rolled off the runway. >> > >> > When I added power to taxi clear of the runway the spitting got much >> > worse. So bad, in fact that it seemed to be running on one rotor and >> > there >> > was insufficient thrust to move the plane forward. I tried adjusting >> > mixture and defeating injectors & coils again and the engine eventually >> > stopped. I was able to restart, but had the same symptoms. The rpm was >> > fairly steady at 1100 or so, but this was the max rpm I could get. The >> > EM2 >> > was flip flopping rpm readings 2300...400...2100..800...every couple of >> > seconds. >> > >> > I called Tracy from right there on the taxiway. As always - he took the >> > call and listened to my unscientific whining. Thank you Tracy :) >> > Anyway, >> > his best thought was that it sounded like it might be a coil heat-soak >> > problem. It definitely seems heat related, and my cowl has been running >> > a >> > bit hotter since I installed the new T04 turbo. >> > >> > I pushed (yes pushed) the plane back to the hangar, then tried turning >> > the >> > prop to feel all six compression strokes. To my untrained arm muscles >> > the >> > compressions all felt the same. I ordered 4 new coils and will report >> > if >> > this corrects the problem. Whether it does or not, I see a separate air >> > duct for the coils in my future. The blow tube I installed may not be >> > providing enough cooling. I once tried installing a temp sensor at the >> > coils, but this sent other EM2 temp readings haywire - induced current >> > from the ignition? - so unfortunately I don't have temp readings on the >> > coils. >> > >> > Anyone have additional thoughts on this? >> > >> > Sincerely, >> > Frustrated in Florida (I could add another F at the beginning to help >> > with >> > the .ing alliteration, but I won't) >> > >> > >> > >> > >> > -- >> > Homepage: http://www.flyrotary.com/ >> > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >> > >> >> >> >> -- >> Homepage: http://www.flyrotary.com/ >> Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ >