---------------------------------------------------------- Continental-List Digest Archive --- Total Messages Posted Sun 09/14/08: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:15 AM - IO-520BB - Rough running at idle and low RPM (martymitchell) 2. 11:58 AM - Re: IO-520BB - Rough running at idle and low RPM (Daniel Michaels) 3. 02:05 PM - Re: IO-520BB - Rough running at idle and low RPM (F. Tim Yoder) 4. 03:52 PM - Re: IO-520BB - Rough running at idle and low RPM (martymitchell) ________________________________ Message 1 _____________________________________ Time: 10:15:59 AM PST US Subject: Continental-List: IO-520BB - Rough running at idle and low RPM From: "martymitchell" I have an IO-520BB in my Beech Bonanza that runs rough at idle and low RPM. I have changed the spark plugs, cleaned the injectors, checked the mag timing (just installed after 500 hour inspection and new distributor block), and had a mechanic check the idle fuel pump pressure and idle mixture setting. I also did a compression check and all cylinders are above 60/80. There doesn't seem to be any difference in drop with each mag at various RPM's. I have not changed the ignition wires. Any ideas on other things to look for? Thanks! -------- Marty Mitchell Bonanza N44GN Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4247#204247 ________________________________ Message 2 _____________________________________ Time: 11:58:37 AM PST US From: Daniel Michaels Subject: Re: Continental-List: IO-520BB - Rough running at idle and low RPM Cleaning the injectors sometimes creates more problems. I would start there then go to the splitter and look for flow problems. You can test the flow -I think at each injector. If you had an engine monitor it should tell yo u which cylinder to look at. Also look for an air-leak in the intake syst em. - Dan --- On Sun, 9/14/08, martymitchell wrote: From: martymitchell Subject: Continental-List: IO-520BB - Rough running at idle and low RPM I have an IO-520BB in my Beech Bonanza that runs rough at idle and low RPM. I have changed the spark plugs, cleaned the injectors, checked the mag timing (just installed after 500 hour inspection and new distributor block), and h ad a mechanic check the idle fuel pump pressure and idle mixture setting. I also did a compression check and all cylinders are above 60/80. There doesn't seem to be any difference in drop with each mag at various RPM's. I have not changed the ignition wires. Any ideas on other things to look for? Thanks! -------- Marty Mitchell Bonanza N44GN Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4247#204247 =0A=0A=0A ________________________________ Message 3 _____________________________________ Time: 02:05:48 PM PST US From: "F. Tim Yoder" Subject: Re: Continental-List: IO-520BB - Rough running at idle and low RPM Does it smooth out if you lean it at idle? Tim ----- Original Message ----- From: "martymitchell" Sent: Sunday, September 14, 2008 10:13 AM Subject: Continental-List: IO-520BB - Rough running at idle and low RPM > > I have an IO-520BB in my Beech Bonanza that runs rough at idle and low RPM. I have changed the spark plugs, cleaned the injectors, checked the mag timing (just installed after 500 hour inspection and new distributor block), and had a mechanic check the idle fuel pump pressure and idle mixture setting. > > I also did a compression check and all cylinders are above 60/80. There doesn't seem to be any difference in drop with each mag at various RPM's. I have not changed the ignition wires. > > Any ideas on other things to look for? > > Thanks! > > -------- > Marty Mitchell > Bonanza N44GN > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p 4247#204247 > > ________________________________ Message 4 _____________________________________ Time: 03:52:16 PM PST US Subject: Continental-List: Re: IO-520BB - Rough running at idle and low RPM From: "martymitchell" Thanks Tim and Dan. Yes, it smooths out quite a bit when I lean it out (about two inches of throttle position) but still misfires. I did clean the injectors with Hoppes #9 gun cleaner but no change. I'm not sure how to check for air leaks other than to verify tightness of all hose clamps and intake bolts. Also, how do you test injector flow? Do you remove them, then capture fuel thru each one into a cup simultaneously and compare levels? I have Gami's, so I would expect different levels in Front, Middle and Back positions. Do you use the boost pump for the test (can't use the engine driven pump)? I do have an engine monitor (EDM-700) and there's nothing too out of place at cruise, can't tell at idle as numbers tend to be all over the place. Thanks... -------- Marty Mitchell Bonanza N44GN Read this topic online here: http://forums.matronics.com/viewtopic.php?p 4292#204292 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message continental-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Continental-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/continental-list Browse Digests http://www.matronics.com/digest/continental-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.