Something I did not mention was that two flights ago, I was drawing outside air from the front of the cowl through the filtered airbox directly into the carb. The last flight I had which lasted 1.4 hours, I had closed the front of the cowl and was drawing air into the carb from inside the cowl. This warm air entered the filtered airbox before the carb. Today's flight was the same set up, closed cowl drawing air from inside the cowl.
Mark Jones (N886MJ) Wales, WI Visit my web site: www.flykr2s.com E-mail: flyk...@wi.rr.com ----- Original Message ----- From: "david stroud" <dstr...@storm.ca> To: "Mark Jones" <flyk...@wi.rr.com> Sent: Thursday, November 23, 2006 4:34 PM Subject: Re: CorvAircraft> I give up !!!! Not... >I haven't been following your posts close enough to know what cht and > egt info you have onboard. You certainly wouldn't have had time at 240' or > so to make note of such things, but were you able to see any temp > excursions > while the hiccup happened at 4000'? > > What I am getting at, is that I had serious hicupp problems with my Vair > engine > ( and none of it was related to the Vair engine proper) when I had the > Holley > 2300 carb installed. It performed flawlessly on my Soob in all flight > attitudes > and that was the reason I installed it on my Vair. Only one slight mod was > done > to finish up the air box installation and that was to saw off flush the > 3/16" float > bowl vent tube which normally stood about 1/2" tall and the end of it was > cut > off at about 45 deg. The engine would run like a banshee on the ground and > in > level flight but, you guessed it, in climb attitude it would balk, hiccup > etc. call it > what you want but I got myself real proficient at emergency landings. The > only > thing that ever got changed on that carb was my cutting off the vent tube. > I never > cured the problem and can only surmise that by cutting off the vent tube, > I screwed > up some precious and necessary airflow ( or non airflow ) that was needed > to vent the > float bowl correctly and in a climb attitude the float bowl starved > (leaned) enough > to cause the condition we are talking about. I've said it before that I > hate frigging with > carbs, especially on an experimental installation and I hate that feeling > in your gut even > more when things start to crap out just when you've got little room to > spare. My suspicion > is that you have some kind of airflow dynamic that changes when you get > into a climb > attitude or even level flight whereby things lean out with no pilot input. > Could even be an > airflow thing in climb and ice another time in level flight. My cure and > I'm not making a > recommendation here, was to change carbs just because I couldn't figure > the damn thing > out myself. When you're this deep into things, quite often no one else is > available to help > cure the problem either. People are just not around when the stuff goes > into the fan. I > switched to the ultra simple Zenith (quasi old Harley) sidedraft carb > thanks to help from > Erik Meisterman and Clare Snyder and never looked back. Not one burp and > saved > about 10lbs in the transfusion. > If you don't solve the problem, be kindly advised that it will not only > remain a threat, it > will gnaw on your gut, make you less likely to enjoy flying, make your > family and friends > less confident in your abilities and in general, make the Corvair engine > and perhaps > homebuilding at large, a less than desirable proposition. I have every > confidence that > you will do the right thing. If you can't figure it out and cure the > existing configuration, > change out the frigging carb. Get a Marvellous Schlepper that Prince > William recommends > and put your troubles behind you. Easy, eh? > > This is an important subject, Mark...could we please change the subject > line to something > appropriate? Some others might learn something from this thread. > > > David Stroud Ottawa, Canada > C-FDWS Christavia > Fairchild 51 under construction > > ----- Original Message ----- > From: "Mark Jones" <flyk...@wi.rr.com> > To: "david stroud" <dstr...@storm.ca> > Sent: Thursday, November 23, 2006 4:49 PM > Subject: Re: CorvAircraft> I give up !!!! Not... > > >> Today, yes. Two flights ago, no, I was in level flight at 4000'. >> >> Mark Jones (N886MJ) >> Wales, WI >> Visit my web site: www.flykr2s.com >> E-mail: flyk...@wi.rr.com >> ----- Original Message ----- >> From: "david stroud" <dstr...@storm.ca> >> To: "Mark Jones" <flyk...@wi.rr.com>; "Corvair engines for homebuilt >> aircraft" <corvaircr...@mylist.net> >> Sent: Thursday, November 23, 2006 3:46 PM >> Subject: Re: CorvAircraft> I give up !!!! Not... >> >> >> > Mark, please read my question carefully. Is it only hiccupping when in >> > climb attitude? >> > >> > David Stroud Ottawa, Canada >> > C-FDWS Christavia >> > Fairchild 51 under construction >> > >> > >> > ----- Original Message ----- >> > From: "Mark Jones" <flyk...@wi.rr.com> >> > To: "KRnet" <kr...@mylist.net>; "Corvair Net" <corvaircr...@mylist.net> >> > Sent: Thursday, November 23, 2006 3:01 PM >> > Subject: CorvAircraft> I give up !!!! Not... >> > >> > >> >> Thanksgiving Day here in Wisconsin is absolutely beautiful with clear >> >> skies, calm winds and 54° F. I could not resist >> > the temptation to go and do some touch and goes. Everything in pre >> > flight >> > and run up were perfect. I taxied out to runway >> > 28 and fire walled her. She revved up to 3200 as I lifted off the >> > pavement >> > and then at 200' she hiccupped. I immediately >> > checked the interstate in front of me for traffic as I continued to >> > climb >> > out. Fortunately there were no more problems on >> > the circuit as I decided that I would do a t&g. I touched down at 70 >> > mph, >> > raised the speed brake, slowly applied throttle >> > and started climbing out. At 300' she hiccupped. So did my heart!!! >> > Then, >> > I decided to start my crosswind and at 450' she >> > hiccupped again as well as my heart. I started talking her around the >> > pattern and she ran fine the rest of the way in and >> > again brought me home safe. Now on the ground, she taxied in with no >> > problems and when I performed more run ups, there >> > was again no indication of problems. Something is apparently starting >> > to >> > crap out and I just wish I could find it. It >> > would be really nice to go for a flight again without having to worry. >> >> >> >> Hope everyone has a Happy Thanksgiving. >> >> >> >> Mark Jones (N886MJ) >> >> Wales, WI >> >> Visit my web site: www.flykr2s.com >> >> E-mail: flyk...@wi.rr.com >> >> _________________________________________________________ >> >> search the CorvAircraft archives at >> >> http://www.maddyhome.com/corvairsrch/index.jsp >> >> to UNsubscribe from CorvAircraft, send a message to >> >> corvaircraft-le...@mylist.net >> >> Other CorvAircraft list info is at >> >> http://www.krnet.org/corvaircraft_inst.html >> >> >> >> >> >> >> >> >> >> -- >> >> No virus found in this incoming message. >> >> Checked by AVG Free Edition. >> >> Version: 7.1.409 / Virus Database: 268.14.14/547 - Release Date: >> >> 11/22/06 >> >> >> >> >> >> >> >> >> -- >> No virus found in this incoming message. >> Checked by AVG Free Edition. >> Version: 7.1.409 / Virus Database: 268.14.14/547 - Release Date: 11/22/06 >> >>
