---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Sun 06/15/08: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:19 PM - Question on EGT on Jab3300 (Juan Vega) 2. 07:16 PM - Re: Question on EGT on Jab3300 (Paul Mulwitz) 3. 07:22 PM - Re: Question on EGT on Jab3300 (jetboy) 4. 08:03 PM - Re: [Probable Spam] Question on EGT on Jab3300 (LarryMcFarland) ________________________________ Message 1 _____________________________________ Time: 06:19:12 PM PST US From: Juan Vega Subject: Zenith-List: Question on EGT on Jab3300 Question to the Engine geniuses on this site. My CHTs are all reading great, between 267 and 280 on all 6 cylinders on my Jabiru. Number 5, the right rear most side has an EGT of 1400 and all other EGTs are reading 1300 to 1320. so they read as follows EGT 1310 1320 1315 1315 1400 1320 Why are the CHTs running great but the 5th cylinder EGTs running hoter by 100 degrees than rest? Anythoughts? Juan Vega Jabiru 3300 ________________________________ Message 2 _____________________________________ Time: 07:16:29 PM PST US From: Paul Mulwitz Subject: Re: Zenith-List: Question on EGT on Jab3300 Hi Juan, It may be that your #5 jug is running hotter or it may be the sensor is measuring it differently from the other ones. Is there a way you can swap sensors between 3 and 5 and see if the hot jug moves? If it does, you know it is a measurement issue rather than something about the engine itself. Fortunately, I think the difference you are seeing is not a problem. It may just wind up being one of those curious things that you never figure out. Have fun, Paul XL getting close to done >Number 5, the right rear most side has an EGT of 1400 and all other >EGTs are reading 1300 to 1320. so they read as follows >EGT 1310 > 1320 > 1315 > 1315 > 1400 > 1320 > >Why are the CHTs running great but the 5th cylinder EGTs running >hoter by 100 degrees than rest? > >Anythoughts? > >Juan Vega Jabiru 3300 ________________________________ Message 3 _____________________________________ Time: 07:22:01 PM PST US Subject: Zenith-List: Re: Question on EGT on Jab3300 From: "jetboy" Juan, aside from probe placement being effectively different from the point of view of the gasflows, if you have a cylinder thats leaner than others and is near its peak EGT or running on the lean side of peak, the CHT on that cyl. will be less than for another cyl. running on the rich side of peak EGT. With the bing carb there is not much you can do other than rotate the carb to balance the mixtures (bottom of carb rotates towards the leaner cyl bank by 5 to 10 degs) or lag the #5 pipe with insulation if they are in a cold airstream. Also check there is no intake leaks or cyl. head to barrel leak. Ralph -------- Ralph - CH701 / 2200a Read this topic online here: http://forums.matronics.com/viewtopic.php?p=188035#188035 ________________________________ Message 4 _____________________________________ Time: 08:03:04 PM PST US From: LarryMcFarland Subject: Re: [Probable Spam] Zenith-List: Question on EGT on Jab3300 Juan, Not being an engine guy, I'd first exchange the sensor with another cylinder and try that. Then, consider why the mixture might be leaner on that particular cylinder. i.e., consider how more air or less fuel might be feeding into that particular cylinder. and lastly, perhaps how that cylinder's exhaust manifold may be different from the others as proximate to internal exhaust flow, valve gap and firing order, etc. This is not likely caused by external temps, airflow, or cooling, but should be found as an internal issue driven by the internal mechanicals. Larry McFarland 601HDS at www.macsmachine.com Juan Vega wrote: > > Question to the Engine geniuses on this site. My CHTs are all reading great, between 267 and 280 on all 6 cylinders on my Jabiru. > > Number 5, the right rear most side has an EGT of 1400 and all other EGTs are reading 1300 to 1320. so they read as follows > EGT 1310 > 1320 > 1315 > 1315 > 1400 > 1320 > > Why are the CHTs running great but the 5th cylinder EGTs running hoter by 100 degrees than rest? > > Anythoughts? > > Juan Vega Jabiru 3300 > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith-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/zenith-list Browse Digests http://www.matronics.com/digest/zenith-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.