---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Thu 09/20/07: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:08 AM - 601 XL overheating (E.T.Gmerek) 2. 08:09 PM - Re: 601 XL overheating (Don Morrisey) 3. 09:21 PM - Re: 601 XL overheating (T. Graziano) ________________________________ Message 1 _____________________________________ Time: 06:08:34 AM PST US From: "E.T.Gmerek" Subject: JabiruEngine-List: 601 XL overheating Do not archive. I=92ve read the recent messages regarding the Jabiru 3300 engine in other than a Jabiru. I have been unable to achieve CHTs within Jabiru=92s guidelines. Many thanks to the people that gave me the benefit of their own experiences with a special thank you to Jeff Small who worked with us for several months trying to help. Just for the record, my configuration is an original(older, mechanical lifters/less cooling fins) engine with a Sensenich Carbon Fiber ground adjustable prop and the latest Jabiru 601 cowling, and a Grand Rapids EIS. The engine has about 56 hours on it at this point, the carburetor was replaced with an NOS pre-economizer change carb to be sure the engine was not running lean, all probes have been checked and rechecked, air leaks in the intake system have been eliminated (there were none), compression checks made (hot and cold, automotive and aircraft), valves adjusted every five hours, a =91lip=92 of about 1 =BD to 2 inches has been added to the bottom of the cowl at the air exit to give a greater differential, cowling sealed, baffling =91tweaked=92 repeatedly adding =91fingerlets=92, speed bumps, an additional vertical baffling =91extension=92 at the #6 cylinder, pictures taken of the entire engine compartment as well as very detailed ones of the baffling. These were reviewed by the Jabiru dealer on the West Coast and nothing wrong was seen. I=92m sure there have been other things done, I=92m just trying to demonstrate that we have tried just about everything possible, without success. The latest numbers at the end of this post indicate we still have a very large problem. I=92d like to ask if anyone has attempted to install baffling which would be more the conventional Continental/Lycoming style, i.e. baffling that directs the ram air over the bottom of the cylinders, not just the top. The Sonex has a system for the 3300 that does just this, and, with some alterations, would fit beneath the cowling of a 601. Obviously the steep slope of the Sonex cowl would call for some change of the baffling, but I called the Sonex site and had the measurements taken directly off their demo and there would not be a very great change to their existing =91baffle box=92. My feeling is that there is inadequate cooling air with the 601/Jabiru cowl and the =91full upper/lower=92 cylinder baffling would make better, more complete use of what is available. The cost is not excessive, $250 plus shipping, and I=92m at the end of my rope. My next step is to replace my Jabiru engine with a Corvair. They don=92t have overheating problems as the full cylinder heads (3 cylinders per) distribute/dissipate heat more efficiently/evenly. The individual I bought the plane from sold it at 26 hours because he could not solve the problem. He was wiser than I. Thoughts/comments appreciated. The latest flight test runs follow: FLIGHT 9-10-2007 --------------------------------- INITIAL CLIMB OUT 283 299 298 351 274 323 --------------------------------- CRUISE 3000rpm 110mph indicated 295 321 331 324 274 303 --------------------------------- CRUISE 2900rpm 110mph indicated 270 291 320 303 269 292 --------------------------------- CRUISE 2800rpm 105mph indicated 271 282 312 299 266 291 --------------------------------- TOP SPEED RUN 3300rpm 120mph indicated oil temp set off alarm at 246 --------------------------------- these next numbers are in unknown configuration but occured after the top speed run 301 314 333 326 262 270 --------------------------------- another 2800rpm CRUISE 269 281 304 299 271 298 oil temp 218 --------------------------------- 500fpm climb at 2800rpm 95mph ind 217 oil temp 277 285 316 308 280 307 updated a little later 284 296 328 326 294 322 9/19/2007 3:59 PM ________________________________ Message 2 _____________________________________ Time: 08:09:18 PM PST US From: Don Morrisey Subject: RE: JabiruEngine-List: 601 XL overheating JP, go to the yahoo groups jabiru engine email list and sign up. Then do a search for "Fisher Dakotahawk". A recent post from a builder in New Zeala nd did exactly what you are thinking...built the standard lyc/conti air box and got excellent results after everything else he tried failed. Another builder on the list has photos in the photo section of a crossover tube he put between the fiberglass airboxes which helped his problem. It seems to me the standard air box accomplishes both. You could use the vertical piec es of the Sonex air box and rivet on extensions to come up to the top of yo ur cowl and basically create the lyc/conti style box. I plan to install my new engine (ser # 1390) this winter with the fiberglass ducts as provided but if that doesn't work I will quickly switch to what I just described. G ood luck. Don...www.donsbushcaddy.comDon Morrisey's Skunkworks From: jptook@jptook.cnc.netTo: jabiruengine-list@matronics.comSubject: Jabi ruEngine-List: 601 XL overheatingDate: Thu, 20 Sep 2007 06:07:27 -0700 Do not archive. I=92ve read the recent messages regarding the Jabiru 3300 engine in other t han a Jabiru. I have been unable to achieve CHTs within Jabiru=92s guidelin es. Many thanks to the people that gave me the benefit of their own experie nces with a special thank you to Jeff Small who worked with us for several months trying to help. Just for the record, my configuration is an original (older, mechanical lifters/less cooling fins) engine with a Sensenich Carbo n Fiber ground adjustable prop and the latest Jabiru 601 cowling, and a Gra nd Rapids EIS. The engine has about 56 hours on it at this point, the carbu retor was replaced with an NOS pre-economizer change carb to be sure the en gine was not running lean, all probes have been checked and rechecked, air leaks in the intake system have been eliminated (there were none), compress ion checks made (hot and cold, automotive and aircraft), valves adjusted ev ery five hours, a =91lip=92 of about 1 =BD to 2 inches has been added to t he bottom of the cowl at the air exit to give a greater differential, cowli ng sealed, baffling =91tweaked=92 repeatedly adding =91fingerlets=92, speed bumps, an additional vertical baffling =91extension=92 at the #6 cylinder, pictures taken of the entire engine compartment as well as very detailed o nes of the baffling. These were reviewed by the Jabiru dealer on the West C oast and nothing wrong was seen. I=92m sure there have been other things do ne, I=92m just trying to demonstrate that we have tried just about everythi ng possible, without success. The latest numbers at the end of this post in dicate we still have a very large problem. I=92d like to ask if anyone has attempted to install baffling which would b e more the conventional Continental/Lycoming style, i.e. baffling that dire cts the ram air over the bottom of the cylinders, not just the top. The Son ex has a system for the 3300 that does just this, and, with some alteration s, would fit beneath the cowling of a 601. Obviously the steep slope of the Sonex cowl would call for some change of the baffling, but I called the So nex site and had the measurements taken directly off their demo and there w ould not be a very great change to their existing =91baffle box=92. My feel ing is that there is inadequate cooling air with the 601/Jabiru cowl and th e =91full upper/lower=92 cylinder baffling would make better, more complete use of what is available. The cost is not excessive, $250 plus shipping, a nd I=92m at the end of my rope. My next step is to replace my Jabiru engine with a Corvair. They don=92t have overheating problems as the full cylinde r heads (3 cylinders per) distribute/dissipate heat more efficiently/evenly . The individual I bought the plane from sold it at 26 hours because he cou ld not solve the problem. He was wiser than I. Thoughts/comments appreciated. The latest flight test runs follow: FLIGHT 9-10-2007---------------------------------INITIAL CLIMB OUT283 299 298351 274 323---------------------------------CRUISE 3000rpm 110mph ind icated295 321 331324 274 303---------------------------------CRUISE 290 0rpm 110mph indicated270 291 320303 269 292---------------------------- -----CRUISE 2800rpm 105mph indicated271 282 312299 266 291------------- --------------------TOP SPEED RUN 3300rpm 120mph indicatedoil temp set off alarm at 246---------------------------------these next numbers are in unkn own configuration but occured after the top speed run301 314 333326 262 270---------------------------------another 2800rpm CRUISE269 281 304299 271 298oil temp 218---------------------------------500fpm climb at 2800 rpm 95mph ind217 oil temp277 285 316308 280 307updated a little later28 4 296 328326 294 322 9/19/2007 3:59 PM _________________________________________________________________ Gear up for Halo=AE 3 with free downloads and an exclusive offer. It=92s ou r way of saying thanks for using Windows Live=99. http://gethalo3gear.com?ocid=SeptemberWLHalo3_WLHMTxt_2 ________________________________ Message 3 _____________________________________ Time: 09:21:45 PM PST US From: "T. Graziano" Subject: JabiruEngine-List: Re: 601 XL overheating Instead of the "air dam" for the oil cooler, I used rubber engine baffeling type material to seal off most of the gaps around the oil cooler to cowling so that air mostly passes through the oil cooler and not around it. Also, of course as mentioned here many times, I only fill my oil to a max of about 40% on the dip stick. In hot weather, in the 90+F area, I still can not go high power low airspeed for long without going red line on CHT (always my #2, the left hand fwd cylinder.) I also have deflectors in the ducts for my #4 and #3 cylinders, about 3/4 inch by 4 inches and bigger deflectors for the #5 and #6. Do not close off the rear area where the duct ends around the #6 and #5 cylinder. Also, see below from my archives for anything that may help. Note: this was with the original economy mod, before the amendment to lower the EGTs Tony Graziano 601XL/Jab3300; N493TG, 291 hours Submitted By: charles.long@gm.com Email List: Zenith-List Name: Charles F. Long Date: Oct 23 2005 Subject: Cooling improvements on the Zenith 601HDS w/Jabiru 3300 Description: During my first few hours of flight, I experienced elevated cylinder head temperatures on my Zenith 601HDS with Jabiru 3300A engine. Also had issues with Exhaust Gas Temperature imbalance at full throttle. The following is a summary of changes made to improve the situation. This really just builds on the recommendations of Jabiru and Zenith to provide plenty of cooling for the 6 cylinder engine. I would like to thank Jeff Small, Fred Hulen, Stan Challgren as well as Pete Krotje at US Jabiru and Andy Sylvester at Sun Coast for their contributions. As a place to start, US Jabiru provides some good cooling suggestions at their website: My aircraft has the following modifications: 1) Fuel Economy Carb Kit as supplied by Jabiru. 2) Gull wing baffles between cylinders as recommended by Jabiru 3) Full deflectors angled down between the spark plugs of cylinder #5 & #6 as recommended by Jabiru. 4) Smaller deflectors angled down between the spark plugs of #3 & #4. These middle cylinder deflectors usually need some tuning. Would suggest starting with 3/4" tall. On #3, I stayed at 3/4", on #4 ended up trimming down to 1/2". 5) The inlet to the ram air ducts has a gap between the duct and the cylinders at the bottom. This allows air to escape downward without doing any useful work. I added some .025" aluminum plates that butt up against cylinder's #1 & #2 to prevent this from happening. To reduce the over cooling of the front two cylinders and force more air upward to the rear cylinders, I angled the material upward about an 2-3=A1=A8. The exact height needs to be determined by trial end error. The new XL cowl has openings that are quite small and located high on the cylinders. My modification attempts to duplicate the XL cowl openings and seems to work quite well. At the onset, this change appears to be counter-intuitive. Just keep it mind, the goal is to get as much use out of every air molecule as possible! 6) Small baffles mounted between valve tappet covers. This prevents more air from escaping without doing any useful work. 7) There is a temptation to add an L angle to the bottom rear of each ram duct. I tried this change and it elevated my temps rather than reducing them. 8) The oil cooler inlet is keep quite small to allow more air to find it's way through the cylinders. I ended up with about a 1.75" x 4.00" opening. The Jabiru website provides a good discussion on this. I tried a much bigger opening as can be seen in the picture and it provided very little benefit. 9) Don't forget to keep your oil level midway between the Full and Add mark. Jabiru indicates that overfilling can cause high oil temps. My #1 cylinder was running much cooler than the #2 cylinder with identical intake openings. I rotated the bottom of the carb 5-10 degrees towards #1 and that took care of it. The main jet feeds the carb at the bottom so if the carb is tilted, it can direct more fuel towards one bank of cylinders than the other. At full throttle, EGT's from left to right bank were 150 F different. I suspected that air entering the carb through the 90 degree intake elbow was piling up on the outside of the curve. I installed a vertical divider in the elbow to keep left side air separated from the right side air. This worked beautifully. My EGT's are now balanced within roughly 50 F at all throttle settings including WOT. The divider was fabricated out of a piece of 6061T6 aluminum - 5.25" x 3" x .016". The upper and lower edges were rolled around a 1/16" cable to add stiffness and prevent cutting of the rubber elbow. Finished height is just slightly over 2.25 inches so it fits snuggly within the elbow. After rolling the edges, the part was bent 90 degrees to fit the elbow contour by wrapping around a 2" diameter plastic pipe. After it springs back, you end up with a 2" bend radius whichis equivalent to the center radius of the elbow. Once the part is finished, the cable can be removed (prevents a potential corrosion issue). The rubber elbow is quite pliable in the free state, so the flow divider installs quite easily. After installation, the divider is trapped pretty well in all directions. With the Aid of my Engine Information System from Grand Rapids Technology, I was able to monitor my progress for each Cylinder Head Temperature: I now have the following readings at 60 F ambient temperature (my engine has 28 hours TT, so temps have fallen after break-in): -------------------------------------------------------------------- RPM IAS CHT1 CHT2 CHT3 CHT4 CHT5 CHT6 EGT5 EGT6 -------------------------------------------------------------------- 2600 110 247 228 259 247 272 245 1465 1423 2700 120 242 221 253 239 265 240 1486 1451 2800 125 242 226 252 242 265 244 1512 1498 2900 130 253 246 260 260 268 262 1482 1538 WOT 138 288 293 293 298 301 297 1463 1482 -------------------------------------------------------------------- This was a quickie test and temps/speeds were not totally stabilized. Oil temps varied from 200-230F depending on Throttle setting. This is an area where a NACA inlet could improve Oil Cooler efficiency. The new XL cowl incorporates one of these. The Flight Test was run at 3500 ft MSL and an ambient of 60F. Wheel pants and gear fairings are installed with an otherwise stock airframe. The Jabiru is running very nice. I'm happy with the installation, power and smoothness after getting through these initial teething problems. Fuel burn at lower cruise settings is estimated at a miserly 4 gph. With the fat wing, I suspect fuel burn will go way up at the higher cruise speeds. Chuck Long Zodiac 601HDS N601LE, 28 hr TT ------------------------- Subject: Subject: 601 XL overheating From: E.T.Gmerek (jptook@jptook.cnc.net) Date: Thu Sep 20 - 6:08 AM Do not archive. I=92ve read the recent messages regarding the Jabiru 3300 engine in other than a Jabiru. I have been unable to achieve CHTs within Jabiru=92s guidelines. Many thanks to the people that gave me the benefit of their own experiences with a special thank you to Jeff Small who worked with us for several months trying to help. Just for the record, my configuration is an original(older, mechanical lifters/less cooling fins) engine with a Sensenich Carbon Fiber ground adjustable prop and the latest Jabiru 601 cowling, and a Grand Rapids EIS. The engine has about 56 hours on it at this point, the carburetor was replaced with an NOS pre-economizer change carb to be sure the engine was not running lean, all probes have been checked and rechecked, air leaks in the intake system have been eliminated (there were none), compression checks made (hot and cold, automotive and aircraft), valves adjusted every five hours, a =91lip=92 of about 1 =BD to 2 inches has been added to the bottom of the cowl at the air exit to give a greater differential, cowling sealed, baffling =91tweaked=92 repeatedly adding =91fingerlets=92, speed bumps, an additional vertical baffling =91extension=92 at the #6 cylinder, pictures taken of the entire engine compartment as well as very detailed ones of the baffling. These were reviewed by the Jabiru dealer on the West Coast and nothing wrong was seen. I=92m sure there have been other things done, I=92m just trying to demonstrate that we have tried just about everything possible, without success. The latest numbers at the end of this post indicate we still have a very large problem. I=92d like to ask if anyone has attempted to install baffling which would be more the conventional Continental/Lycoming style, i.e. baffling that directs the ram air over the bottom of the cylinders, not just the top. The Sonex has a system for the 3300 that does just this, and, with some alterations, would fit beneath the cowling of a 601. Obviously the steep slope of the Sonex cowl would call for some change of the baffling, but I called the Sonex site and had the measurements taken directly off their demo and there would not be a very great change to their existing =91baffle box=92. My feeling is that there is inadequate cooling air with the 601/Jabiru cowl and the =91full upper/lower=92 cylinder baffling would make better, more complete use of what is available. The cost is not excessive, $250 plus shipping, and I=92m at the end of my rope. My next step is to replace my Jabiru engine with a Corvair. They don=92t have overheating problems as the full cylinder heads (3 cylinders per) distribute/dissipate heat more efficiently/evenly. The individual I bought the plane from sold it at 26 hours because he could not solve the problem. He was wiser than I. Thoughts/comments appreciated. From: E.T.Gmerek (jptook@jptook.cnc.net) Date: Thu Sep 20 - 6:08 AM Do not archive. I=92ve read the recent messages regarding the Jabiru 3300 engine in other than a Jabiru. I have been unable to achieve CHTs within Jabiru=92s guidelines. Many thanks to the people that gave me the benefit of their own experiences with a special thank you to Jeff Small who worked with us for several months trying to help. Just for the record, my configuration is an original(older, mechanical lifters/less cooling fins) engine with a Sensenich Carbon Fiber ground adjustable prop and the latest Jabiru 601 cowling, and a Grand Rapids EIS. The engine has about 56 hours on it at this point, the carburetor was replaced with an NOS pre-economizer change carb to be sure the engine was not running lean, all probes have been checked and rechecked, air leaks in the intake system have been eliminated (there were none), compression checks made (hot and cold, automotive and aircraft), valves adjusted every five hours, a =91lip=92 of about 1 =BD to 2 inches has been added to the bottom of the cowl at the air exit to give a greater differential, cowling sealed, baffling =91tweaked=92 repeatedly adding =91fingerlets=92, speed bumps, an additional vertical baffling =91extension=92 at the #6 cylinder, pictures taken of the entire engine compartment as well as very detailed ones of the baffling. These were reviewed by the Jabiru dealer on the West Coast and nothing wrong was seen. I=92m sure there have been other things done, I=92m just trying to demonstrate that we have tried just about everything possible, without success. The latest numbers at the end of this post indicate we still have a very large problem. I=92d like to ask if anyone has attempted to install baffling which would be more the conventional Continental/Lycoming style, i.e. baffling that directs the ram air over the bottom of the cylinders, not just the top. The Sonex has a system for the 3300 that does just this, and, with some alterations, would fit beneath the cowling of a 601. Obviously the steep slope of the Sonex cowl would call for some change of the baffling, but I called the Sonex site and had the measurements taken directly off their demo and there would not be a very great change to their existing =91baffle box=92. My feeling is that there is inadequate cooling air with the 601/Jabiru cowl and the =91full upper/lower=92 cylinder baffling would make better, more complete use of what is available. The cost is not excessive, $250 plus shipping, and I=92m at the end of my rope. My next step is to replace my Jabiru engine with a Corvair. They don=92t have overheating problems as the full cylinder heads (3 cylinders per) distribute/dissipate heat more efficiently/evenly. The individual I bought the plane from sold it at 26 hours because he could not solve the problem. He was wiser than I. Thoughts/comments appreciated. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message jabiruengine-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/JabiruEngine-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/jabiruengine-list Browse Digests http://www.matronics.com/digest/jabiruengine-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.