---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Tue 08/26/08: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:05 AM - Re: cooling cylinder heads s/n 346 3300 (Larry and Dee Pritchard) 2. 11:33 AM - Re: cooling cylinder heads s/n 346 3300 (bob noffs) 3. 03:11 PM - Re: cooling cylinder heads s/n 346 3300 (Peter and Jan Disher) 4. 10:19 PM - Re: cooling cylinder heads s/n 346 3300 (Ivan) ________________________________ Message 1 _____________________________________ Time: 10:05:12 AM PST US From: "Larry and Dee Pritchard" Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 To: Peter/Jan Disher: I am having CHT problems too and have worked with the air dams inside the ram air ducts.My heads have 3 small vertical holes drilled upward from the bottom that intersect a larger 5/8 inch horizontal hole drilled from the outside of the head that also intersects the upper cooling fins. I have installed a tube to draw cooling air from UNDER the head and dump it over board. I MAY install a cooling air line to the 5/8 dia. hole to put more air into the head to help with cooling. I am told the newer head design does not have these extra holes, what s/n I don't know. I have installed 8mm ring thermocouples under the head bolt above the spark plugs and found them to be about 50-60 F degrees lower than the 12mm ring thermocouples under the plugs, be careful with bolt length! This was NOT a good test. I am also not happy with the fit of the 12mm rings and the plugs. I am now using large copper washers under the plugs with the ring thermocouples between the copper and the head. I also had oil temp problems but seem to be OK now after three oil coolers and 4 years of work and many failed attempts. I ended up with a Positech aviation 200003c cooler with a 1 to 3 area ratio. I now have to worry about low oil temp in the cooler months. I very much want to see more comments on this problem. Larry Pritchard, located in Arizona, 100 to 110+ F degrees ________________________________ Message 2 _____________________________________ Time: 11:33:19 AM PST US From: "bob noffs" Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 larry, consider putting a thermostat in your cooler lines. below 180 deg. it shunts the oil back to the engine without going thru the cooler. i have installed one but am not done building yet. others have said it works well. bob noffs ----- Original Message ----- From: Larry and Dee Pritchard To: jabiruengine-list@matronics.com Sent: Tuesday, August 26, 2008 12:03 PM Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 To: Peter/Jan Disher: I am having CHT problems too and have worked with the air dams inside the ram air ducts.My heads have 3 small vertical holes drilled upward from the bottom that intersect a larger 5/8 inch horizontal hole drilled from the outside of the head that also intersects the upper cooling fins. I have installed a tube to draw cooling air from UNDER the head and dump it over board. I MAY install a cooling air line to the 5/8 dia. hole to put more air into the head to help with cooling. I am told the newer head design does not have these extra holes, what s/n I don't know. I have installed 8mm ring thermocouples under the head bolt above the spark plugs and found them to be about 50-60 F degrees lower than the 12mm ring thermocouples under the plugs, be careful with bolt length! This was NOT a good test. I am also not happy with the fit of the 12mm rings and the plugs. I am now using large copper washers under the plugs with the ring thermocouples between the copper and the head. I also had oil temp problems but seem to be OK now after three oil coolers and 4 years of work and many failed attempts. I ended up with a Positech aviation 200003c cooler with a 1 to 3 area ratio. I now have to worry about low oil temp in the cooler months. I very much want to see more comments on this problem. Larry Pritchard, located in Arizona, 100 to 110+ F degrees ________________________________ Message 3 _____________________________________ Time: 03:11:51 PM PST US From: "Peter and Jan Disher" Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 Hi Larry, I really can't comment at this time for I haven't flown my bird as yet, also our temp. here in Australia where I live may get to 100 Deg in summer only gets down to about 60 Deg in winter. People here tell me all different things like the engine will have heating problems and others tell me I won't, they will be cooling problems, so really I'm not sure what to expect. What I have done is allowed ducted cooling air to the sump that I can control from in the aircraft. I hope to be flying soon. Pete D ----- Original Message ----- From: Larry and Dee Pritchard To: jabiruengine-list@matronics.com Sent: Wednesday, August 27, 2008 3:03 AM Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 To: Peter/Jan Disher: I am having CHT problems too and have worked with the air dams inside the ram air ducts.My heads have 3 small vertical holes drilled upward from the bottom that intersect a larger 5/8 inch horizontal hole drilled from the outside of the head that also intersects the upper cooling fins. I have installed a tube to draw cooling air from UNDER the head and dump it over board. I MAY install a cooling air line to the 5/8 dia. hole to put more air into the head to help with cooling. I am told the newer head design does not have these extra holes, what s/n I don't know. I have installed 8mm ring thermocouples under the head bolt above the spark plugs and found them to be about 50-60 F degrees lower than the 12mm ring thermocouples under the plugs, be careful with bolt length! This was NOT a good test. I am also not happy with the fit of the 12mm rings and the plugs. I am now using large copper washers under the plugs with the ring thermocouples between the copper and the head. I also had oil temp problems but seem to be OK now after three oil coolers and 4 years of work and many failed attempts. I ended up with a Positech aviation 200003c cooler with a 1 to 3 area ratio. I now have to worry about low oil temp in the cooler months. I very much want to see more comments on this problem. Larry Pritchard, located in Arizona, 100 to 110+ F degrees Checked by AVG - http://www.avg.com 8/25/2008 8:48 PM ________________________________ Message 4 _____________________________________ Time: 10:19:57 PM PST US From: "Ivan" Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 My oil temps in Phoenix reach 224F on climbout in 90+ degree weather. I have a J-250 and have had the oil cooler flange installed as per service bulletin with great success Ivan ----- Original Message ----- From: Larry and Dee Pritchard To: jabiruengine-list@matronics.com Sent: Tuesday, August 26, 2008 10:03 AM Subject: Re: JabiruEngine-List: cooling cylinder heads s/n 346 3300 To: Peter/Jan Disher: I am having CHT problems too and have worked with the air dams inside the ram air ducts.My heads have 3 small vertical holes drilled upward from the bottom that intersect a larger 5/8 inch horizontal hole drilled from the outside of the head that also intersects the upper cooling fins. I have installed a tube to draw cooling air from UNDER the head and dump it over board. I MAY install a cooling air line to the 5/8 dia. hole to put more air into the head to help with cooling. I am told the newer head design does not have these extra holes, what s/n I don't know. I have installed 8mm ring thermocouples under the head bolt above the spark plugs and found them to be about 50-60 F degrees lower than the 12mm ring thermocouples under the plugs, be careful with bolt length! This was NOT a good test. I am also not happy with the fit of the 12mm rings and the plugs. I am now using large copper washers under the plugs with the ring thermocouples between the copper and the head. I also had oil temp problems but seem to be OK now after three oil coolers and 4 years of work and many failed attempts. I ended up with a Positech aviation 200003c cooler with a 1 to 3 area ratio. I now have to worry about low oil temp in the cooler months. I very much want to see more comments on this problem. Larry Pritchard, located in Arizona, 100 to 110+ F degrees ------------------------------------------------------------------------------------- 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.