Colin I agree with you 100% Every thing you say is per the manual, I have one and have read it. I wasn't suggesting using the primer while cranking the engine, I just don't remember ever hearing anyone say or reading not to. You stated it as if it was verboten. I agree its not a good idea for the reasons you stated. I also believe that if you don't know how to use a primer you should not be flying an airplane. I also do not want to be dependent on a battery to stay in the air so I believe in gravity feed and mags. Murphy has proven himself to me more than once. I believe you are an instructor and was wondering if you tell your students that when something big goes wrong ( engine quits ) the first thing you do is wind the clock? My instructor did. This gives you time to think instead of just snatching and grabbing, turning and pulling and possibly making things worse but I'm sure you knew what I meant. I think you said you were about to get your ATP, I hope that worked out, and I asked if that's the same as an ATR. Since then i talked to a twenty year American pilot and he said his still is an ATR. Colin you are doing a very good job on this list and I respect you and your accomplishments and in no way mean to dispute anything you've said, as you say. Just my 2 cents worth.
Steve Bray Jackson, Tennessee >From: "Colin Rainey" <brokerpilot9...@earthlink.net> >Reply-To: brokerpilot9...@earthlink.net, KRnet <kr...@mylist.net> >To: kr...@mylist.net >Subject: KR> primer >Date: Wed, 30 Nov 2005 11:53:24 -0500 > >According to the 1980 Cessna 172 manual priming with one to two full >strokes should be sufficient to crank most engines that are cold, in normal >conditions. This should apply well to all KR engines where the manual >primer is properly matched to the engine. In winter up to 6 strokes may be >necessary. Also, priming during starting IS permitted, however a notation >is made to insure that the primer knob is secured prior to beginning flight >operations due to the possibility of drawing fuel through the primer, which >is unregulated, and unmeasured. This is what I meant about unknown amount. >Unless you take one apart, and then measure the injected amount, you have >no idea how much fuel you are putting in, same as the solenoid. Too much >causes cylinder wash which greatly increases the amount of wear on the >engine. MOST low hour pilots over richen their engines, or fail to lean >properly, or at all. The reason we teach not to use while cranking is the >increased fire hazard due to causing a backfire, and the fact that it could >be left unsecured, causing an over rich condition in cruise. This makes for >two problems: 1) Lack of fuel economy expected, which could result in an >emergency landing (number one reason for emergency landings overall, >running out of fuel); 2) fuel fouling plugs causing carbon buildup and >excessive engine wear, low power, and possible engine failure/shutoff in >flight. > >Just because one gets away with doing what is not recommended does not mean >it is correct, or good to do. If the manufacturer does not endorse it, and >they are the "expert" of that setup, then don't do it no matter who >recommends it. There is ALWAYS too much other information missing that >allows that person to use the unusual procedure that doesn't make it on to >the page when talking. > >Just my 2 cents worth... > >Colin Rainey >brokerpilot9...@earthlink.net >EarthLink Revolves Around You. >_______________________________________ >Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp >to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net >please see other KRnet info at http://www.krnet.org/info.html
