---------------------------------------------------------- Jabiru-List Digest Archive --- Total Messages Posted Wed 08/18/10: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:12 PM - ghost in the engine 2200A (tutuzulu) 2. 08:45 PM - Re: ghost in the engine 2200A (Don Honabach) ________________________________ Message 1 _____________________________________ Time: 07:12:18 PM PST US Subject: Jabiru-List: ghost in the engine 2200A From: "tutuzulu" Hi Listers, I have an engine problem that has everybody, mechanics, Jabiru personnel, and of course me, totally bamboozled. Any ideas would be welcome. Here's a review of the problem so far Immediately after the annual inspection in March, the engine began running rough above about 2,650 rpm. It starts with a little roughness, and the longer it runs above that rpm the rougher it gets, and soon the rpm starts bouncing around wildly within a range of about 2,500 to 2,750. One of the cylinders will start cooling down in EGTs and CHTs. Which cylinder it is will change; its nearly always 2 or 4, sometimes 3, and rarely 1. When the power is reduced below about 2,650, the cool cylinder warms up and everything runs smoothly. It seems like after every change (see below), it runs a little bit better for a little while, but then reverts to the same problem. Its interesting that I can run it for a while and have the problem be on one cylinder, then shut it down for 5 minutes and then start it again and have the problem be on another cylinder. The following have resulted in no change: L, R, or Both magnetos. Carb heat On or Off. Electric fuel pump On or Off. Replaced rotors, distributor cap, spark plug wires, and sparkplugs. New carburetor. (The only difference this made was that a couple EGTs ran too high.) Inspections that were normal: Ive removed the carb and looked into the intake manifold but could see no obstructions or abnormalities. There was no metal in the oil filter. All the valve springs appear to have the same resistance when I push on them. The rocker arms all appear perfectly aligned when in the full up/out position. I also removed the air intake Scat hose and tried running it with carb intake open to the engine compartment, with both the old and a new carb. No difference. I'm grounded and heartbroken. Anybody got any ideas? Many thanks, Bob Miller -------- Bob Miller Read this topic online here: http://forums.matronics.com/viewtopic.php?p=309346#309346 ________________________________ Message 2 _____________________________________ Time: 08:45:27 PM PST US From: Don Honabach Subject: RE: Jabiru-List: ghost in the engine 2200A I would have sworn you bumped the intake house during the annual as it sounded like turbulent air going into the carb which would have also made sense considering the cylinders temps, etc. I didn't see anything in your message about fuel testing beyond electric fuel pump on/off. Is it possible the mechanical fuel pump is bad/going bad (I'm assuming the 2200 has a mechanical fuel pump as my 3300A does?). Might be worth it to setup a temporary gravity feed setup that goes direct to the carb so you can bypass all fuel pumps. Good luck and please share when you find out the cause. Don Honabach -----Original Message----- From: owner-jabiru-list-server@matronics.com [mailto:owner-jabiru-list-server@matronics.com] On Behalf Of tutuzulu Sent: Wednesday, August 18, 2010 7:12 PM Subject: Jabiru-List: ghost in the engine 2200A Hi Listers, I have an engine problem that has everybody, mechanics, Jabiru personnel, and of course me, totally bamboozled. Any ideas would be welcome. Here's a review of the problem so far Immediately after the annual inspection in March, the engine began running rough above about 2,650 rpm. It starts with a little roughness, and the longer it runs above that rpm the rougher it gets, and soon the rpm starts bouncing around wildly within a range of about 2,500 to 2,750. One of the cylinders will start cooling down in EGTs and CHTs. Which cylinder it is will change; its nearly always 2 or 4, sometimes 3, and rarely 1. When the power is reduced below about 2,650, the cool cylinder warms up and everything runs smoothly. It seems like after every change (see below), it runs a little bit better for a little while, but then reverts to the same problem. Its interesting that I can run it for a while and have the problem be on one cylinder, then shut it down for 5 minutes and then start it again and have the problem be on another cylinder. The following have resulted in no change: L, R, or Both magnetos. Carb heat On or Off. Electric fuel pump On or Off. Replaced rotors, distributor cap, spark plug wires, and sparkplugs. New carburetor. (The only difference this made was that a couple EGTs ran too high.) Inspections that were normal: Ive removed the carb and looked into the intake manifold but could see no obstructions or abnormalities. There was no metal in the oil filter. All the valve springs appear to have the same resistance when I push on them. The rocker arms all appear perfectly aligned when in the full up/out position. I also removed the air intake Scat hose and tried running it with carb intake open to the engine compartment, with both the old and a new carb. No difference. I'm grounded and heartbroken. Anybody got any ideas? Many thanks, Bob Miller -------- Bob Miller Read this topic online here: http://forums.matronics.com/viewtopic.php?p=309346#309346 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message jabiru-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Jabiru-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/jabiru-list Browse Digests http://www.matronics.com/digest/jabiru-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.