---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Fri 08/22/14: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:31 PM - Tightening head bolts on Jab 2200, which method is best? (Frankd) 2. 03:07 PM - Re: Tightening head bolts on Jab 2200, which method is best? (Tim Yoder) 3. 07:36 PM - Re: Tightening head bolts on Jab 2200, which method is best? (Mark Hubelbank) ________________________________ Message 1 _____________________________________ Time: 12:31:35 PM PST US Subject: JabiruEngine-List: Tightening head bolts on Jab 2200, which method is best? From: "Frankd" Hello, I have a 2200 on a KOLB that I need to do the annual on and one item required is to tighten the head bolts to 24foot-Lbs. Do I unscrew the bolts a little first and then re-tighten to the correct torque or do I just tighten from their current position. I have received answers that recommend both!! from different people. My gut tells me that the correct method is to loosen the bolt first and then tighten to the spec, that way you don't fight the built in friction. Also, it says use anti-seize on these bolts, and if I loosen should I put some anti-seize on them as well? Thanks for your advise FrankD Kolb MkIII Xtra. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=429132#429132 ________________________________ Message 2 _____________________________________ Time: 03:07:35 PM PST US From: "Tim Yoder" Subject: RE: JabiruEngine-List: Tightening head bolts on Jab 2200, which method is best? Frank, Assuming that the head bolts were originally assembled with anti-corrision/anit-seize compound and torque to 24 ft. lbs., you re-torque to 20 ft. lbs. to see if there has been cylinder head over heating. Do not back off the bolt first or you negate the test. If they move, look at your cooling ducts and flight profile for reducing max CHT's. The bolts should not move on this check. This procedure is different, for example, than re-torque of wood props where you do loosen the bolt a little prior to re-torque. These bolts are assembled dry and you loosen them to relieve any binding from corrosion, etc. Hope this helps. Tim -----Original Message----- From: owner-jabiruengine-list-server@matronics.com [mailto:owner-jabiruengine-list-server@matronics.com] On Behalf Of Frankd Sent: Friday, August 22, 2014 12:31 PM Subject: JabiruEngine-List: Tightening head bolts on Jab 2200, which method is best? Hello, I have a 2200 on a KOLB that I need to do the annual on and one item required is to tighten the head bolts to 24foot-Lbs. Do I unscrew the bolts a little first and then re-tighten to the correct torque or do I just tighten from their current position. I have received answers that recommend both!! from different people. My gut tells me that the correct method is to loosen the bolt first and then tighten to the spec, that way you don't fight the built in friction. Also, it says use anti-seize on these bolts, and if I loosen should I put some anti-seize on them as well? Thanks for your advise FrankD Kolb MkIII Xtra. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=429132#429132 --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ________________________________ Message 3 _____________________________________ Time: 07:36:26 PM PST US From: Mark Hubelbank Subject: Re: JabiruEngine-List: Tightening head bolts on Jab 2200, which method is best? You might also note that a lot of Jabiru engines will have some head bolts keep moving for up to the first 100 hours. That was my observation. I carefully monitored CHTs and do believe they were kept within limits at all times. The biggest change was as one would expect in the first few hours but It didn't completely stabilize for a while. Quite different from automotive heads. And generally other aircraft engines don't have head bolts. -- Mark Hubelbank mhubel@nemon.com 978-443-3955 ------------------------------------------------------------------------------------- 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.