---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 04/17/18: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:27 PM - Re: 912 Cylinder head coolant temperature Gauge () 2. 01:47 PM - Re: 912 Cylinder head coolant temperature Gauge (william sullivan) 3. 03:59 PM - Re: 912 Cylinder head coolant temperature Gauge (John Hauck) 4. 06:22 PM - Re: 912 Cylinder head coolant temperature Gauge (Roger Lee) 5. 07:28 PM - Re: Re: 912 Cylinder head coolant temperature Gauge (John Hauck) 6. 07:51 PM - Re: Re: 912 Cylinder head coolant temperature Gauge (John Hauck) 7. 07:54 PM - Re: Re: 912 Cylinder head coolant temperature Gauge (Dave) ________________________________ Message 1 _____________________________________ Time: 01:27:42 PM PST US From: Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge Bill, I know how to "burp" the oil system, but I have never heard of "burping" the coolant system. How is that done? Hugh G. McKay III, P.E. Fellow, L.M. ASCE Senior Consultant Worldwide Engineering Inc. 4090 North NC Hwy. 16 Denver, NC 28037 Ph. 704-661-8271 Fax 704-483-5466 email hgmckay@bellsouth.net http://www.wwegeo.com -----Original Message----- From: william sullivan Sent: Saturday, April 14, 2018 4:41 PM Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge I am thinking the same way John is. You have an air bubble, and is has to be burped. The other option, as always, is a loose wire. Bill Sullivan Tarboro, NC (recently escaped from Connecticut!) -------------------------------------------- On Sat, 4/14/18, wrote: Subject: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge I have the new cylinder heads on my 912 UL engine. I am measuring the coolant temperature using the normal Rotax (VDO) gauge. During engine operation my gauge needle is quickly fluctuating (swinging) as much as 10 to 30 degrees Ph. 704-661-8271 Fax 704-483-5466 email hgmckay@bellsouth.net http://www.wwegeo.com ________________________________ Message 2 _____________________________________ Time: 01:47:10 PM PST US From: william sullivan Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge I have to plead ignorance on Rotax, but a number of automotive engines will hide an air bubble in the cooling system. The old Jeep 4.0 liter straight 6 was always doing that. You filled it up after working on it, and had to keep filling it for a few days until all of the air worked out of it. Maybe John Hauck knows. It used to drive me nuts, thinking I had a leak and not finding it. I would just fill it, run it, fill it, and run it over a few days, cooling off in between runs. Bill Sullivan -------------------------------------------- On Tue, 4/17/18, wrote: Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge To: rotaxengines-list@matronics.com Date: Tuesday, April 17, 2018, 4:27 PM Bill, I know how to "burp" the oil system, but I have never heard of "burping" the coolant system. How is that done? Hugh G. McKay III, P.E. Fellow, L.M. ASCE Senior Consultant Worldwide Engineering Inc. 4090 North NC Hwy. 16 Denver, NC 28037 Ph. 704-661-8271 Fax 704-483-5466 email hgmckay@bellsouth.net http://www.wwegeo.com -----Original Message----- From: william sullivan Sent: Saturday, April 14, 2018 4:41 PM To: rotaxengines-list@matronics.com Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge --> RotaxEngines-List message posted by: william sullivan I am thinking the same way John is. You have an air bubble, and is has to be burped. The other option, as always, is a loose wire. Bill Sullivan Tarboro, NC (recently escaped from Connecticut!) ________________________________ Message 3 _____________________________________ Time: 03:59:05 PM PST US From: "John Hauck" Subject: RE: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge Here is how I do it. After draining and refilling, I raise the tail higher than the nose, MKIII is a tail dragger, and back down. Top it off and rock it up and back down until I can't put any more coolant into the header tank. I bleed air the same way you describe Bill S. Until the header tank is completely full after a flight, shut down, and cool down, I check the header tank. I keep doing this procedure until all the air is gone. Do the same thing with all my other water cooled engines to bleed air. When all air is gone the coolant recovery tank will hit its high mark with the engine hot and suck coolant out of the coolant recovery tank as it cools. This keeps air out of the system. john h mkIII Titus, Alabama -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of william sullivan Sent: Tuesday, April 17, 2018 3:47 PM Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge I have to plead ignorance on Rotax, but a number of automotive engines will hide an air bubble in the cooling system. The old Jeep 4.0 liter straight 6 was always doing that. You filled it up after working on it, and had to keep filling it for a few days until all of the air worked out of it. Maybe John Hauck knows. It used to drive me nuts, thinking I had a leak and not finding it. I would just fill it, run it, fill it, and run it over a few days, cooling off in between runs. Bill Sullivan -------------------------------------------- On Tue, 4/17/18, wrote: Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge To: rotaxengines-list@matronics.com Date: Tuesday, April 17, 2018, 4:27 PM Bill, I know how to "burp" the oil system, but I have never heard of "burping" the coolant system. How is that done? Hugh G. McKay III, P.E. Fellow, L.M. ASCE Senior Consultant Worldwide Engineering Inc. 4090 North NC Hwy. 16 Denver, NC 28037 Ph. 704-661-8271 Fax 704-483-5466 email hgmckay@bellsouth.net http://www.wwegeo.com -----Original Message----- From: william sullivan Sent: Saturday, April 14, 2018 4:41 PM To: rotaxengines-list@matronics.com Subject: Re: RotaxEngines-List: 912 Cylinder head coolant temperature Gauge --> RotaxEngines-List message posted by: william sullivan I am thinking the same way John is. You have an air bubble, and is has to be burped. The other option, as always, is a loose wire. Bill Sullivan Tarboro, NC (recently escaped from Connecticut!) ________________________________ Message 4 _____________________________________ Time: 06:22:36 PM PST US Subject: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge From: "Roger Lee" The coolant system in the 912 is an open system. The fluid seeks its own level and rarely ever needs more after filling. Because it is an open system it is also very easy to evacuate the entire tire system. Fill and go. With all the hoses changes I do every year I never have trapped air that made a difference. -------- Roger Lee Tucson, Az. Rotax Instructor & Rotax IRC Light Sport Repairman Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=479413#479413 ________________________________ Message 5 _____________________________________ Time: 07:28:29 PM PST US From: "John Hauck" Subject: RE: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge I thought I was flying with a closed cooling system all these years. If it has a pressure cap and coolant recovery system, I call that a closed system. An open system would be like my old antique tractors, unpressurised and open to the atmosphere. I really don't know of an open system on a modern water cooled engine. Set me straight if I am wrong. Not trying to be argumentative. I do know the three 912 engines I have owned since 1993, all required bleeding air and fill/top off through the header tank. There are places in the engine that do trap air. Maybe the newer engines have different castings. john h mkIII Titus, Alabama -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Roger Lee Sent: Tuesday, April 17, 2018 8:22 PM Subject: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge The coolant system in the 912 is an open system. The fluid seeks its own level and rarely ever needs more after filling. Because it is an open system it is also very easy to evacuate the entire tire system. Fill and go. With all the hoses changes I do every year I never have trapped air that made a difference. -------- Roger Lee Tucson, Az. Rotax Instructor & Rotax IRC Light Sport Repairman Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=479413#479413 ________________________________ Message 6 _____________________________________ Time: 07:51:04 PM PST US From: "John Hauck" Subject: RE: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge Roger Lee: Took a quick look in the Rotax 912 Installation Manual. It describes the cooling system as closed. john h mkIII Titus, Alabama -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of John Hauck Sent: Tuesday, April 17, 2018 9:28 PM Subject: RE: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge I thought I was flying with a closed cooling system all these years. If it has a pressure cap and coolant recovery system, I call that a closed system. An open system would be like my old antique tractors, unpressurised and open to the atmosphere. I really don't know of an open system on a modern water cooled engine. Set me straight if I am wrong. Not trying to be argumentative. I do know the three 912 engines I have owned since 1993, all required bleeding air and fill/top off through the header tank. There are places in the engine that do trap air. Maybe the newer engines have different castings. john h mkIII Titus, Alabama -----Original Message----- From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Roger Lee Sent: Tuesday, April 17, 2018 8:22 PM Subject: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge The coolant system in the 912 is an open system. The fluid seeks its own level and rarely ever needs more after filling. Because it is an open system it is also very easy to evacuate the entire tire system. Fill and go. With all the hoses changes I do every year I never have trapped air that made a difference. -------- Roger Lee Tucson, Az. Rotax Instructor & Rotax IRC Light Sport Repairman Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=479413#479413 ________________________________ Message 7 _____________________________________ Time: 07:54:25 PM PST US From: Dave Subject: Re: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge Youre right on. And without the overflow tank with a hose submerged in coolant you will never get rid of the air. Dave Alberti > On Apr 17, 2018, at 9:28 PM, John Hauck wrote: > > > I thought I was flying with a closed cooling system all these years. If it > has a pressure cap and coolant recovery system, I call that a closed system. > > An open system would be like my old antique tractors, unpressurised and open > to the atmosphere. > > I really don't know of an open system on a modern water cooled engine. > > Set me straight if I am wrong. Not trying to be argumentative. > > I do know the three 912 engines I have owned since 1993, all required > bleeding air and fill/top off through the header tank. There are places in > the engine that do trap air. Maybe the newer engines have different > castings. > > john h > mkIII > Titus, Alabama > > > > > -----Original Message----- > From: owner-rotaxengines-list-server@matronics.com > [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Roger Lee > Sent: Tuesday, April 17, 2018 8:22 PM > To: rotaxengines-list@matronics.com > Subject: RotaxEngines-List: Re: 912 Cylinder head coolant temperature Gauge > > > The coolant system in the 912 is an open system. The fluid seeks its own > level and rarely ever needs more after filling. Because it is an open system > it is also very easy to evacuate the entire tire system. > > Fill and go. With all the hoses changes I do every year I never have trapped > air that made a difference. > > -------- > Roger Lee > Tucson, Az. > Rotax Instructor & Rotax IRC > Light Sport Repairman > Home 520-574-1080 TRY HOME FIRST > Cell 520-349-7056 > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=479413#479413 > > > > > > > > > > > > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-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/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-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.