---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Sat 09/10/16: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:08 PM - Re: Rough running 912 UL (Hugh McKay) 2. 04:04 PM - Re: Rough running 912 UL (Dennis Tubbs) 3. 04:10 PM - Re: Rough running 912 UL (Richard Girard) 4. 07:16 PM - Re: Rough running 912 UL (Dashwoodlock) ________________________________ Message 1 _____________________________________ Time: 02:08:41 PM PST US From: "Hugh McKay" Subject: Re: RotaxEngines-List: Rough running 912 UL Gentlemen (bjones,jelling Catz631 h&, Jeff Wemmelring, Bick Girard, John Hauck, Lowell Fitt, Dee LeBlanc, GHeal, et al) Well I found what was causing my rough running engine!! I am some what embarrassed, but it demonstrates how careful one must be when doing anything to a Rotax 912 series engine. All this started when I began to hear excessive engine noise in my head sets when transmitting on my radio. Well, if you read my earlier questions regarding the engine noise you will recall that I was advised (good advice)to first check all the grounds. This I did and found no bad grounds. In the course of checking the grounds there are two grounding points on the right side of the ignition modules where two screws screw down into the engine. One of these ground points has two ground wires attached to it. The other has three ground wires attached. I removed these grounds, cleaned them and reattached them to their proper screw location; or I thought I had. Well, after looking carefully at the top of the engine at these two ground points and feeling all of the wires in that area I found two loose black wires with a common ring terminal tucked under the intake manifold on that side of the engine. Well what a surprise!! Then I began to think, how can that be?? Then I noticed that these two wires with the common ring terminal exactly fit one of the two ground points I have just described. I then realized that I had pushed the end of this double ground wire with the common ring terminal under the manifold to get better access to clean the ground point. What I did not remember when it came time to reattach all the wires was that I had tucked this ground wire out of sight. I reattached all the =93visible=94 ground wires forgetting I had tucked one out of sight. Lesson learned! Make sure you know how many wires you have disconnected, and reconnect the =93same=94 number. Anyway, I am back flying and the engine is running fine. Flew down to the big Triple Tree Fly-In just below Woodruff, SC today with out a problem except the noise in my radio which is another story. Many thanks for all of your suggestions. I value them and your willingness to share. Regards, 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 From: John Hauck Sent: Thursday, September 08, 2016 6:05 PM Subject: RE: RotaxEngines-List: Rough running 912 UL Might be a good time to replace the connectors.=C2 Those have been rapid wear parts on my three 912s.=C2 They can be bought from Sparkplugs.com by getting the part number off of a connector.=C2 Price is a quarter what Rotax wants for them. john h mkIII Burns Junction, Oregon From: owner-rotaxengines-list-server@matronics.com [mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Richard Girard Sent: Thursday, September 08, 2016 3:25 PM Subject: Re: RotaxEngines-List: Rough running 912 UL Hugh, Old mechanics proverb, "90% of carburetor problems are solved in the ignition system". That being said, have you checked the resistance of your spark plug wires? Since you'll have to re-seat the wires anyway, take the time to trim each end about 1/4" so that the screw connector has a chance to seat into fresh, un-corroded wire. Also check the screws themselves for signs of corrosion. Unless the wires are too short afterward this check won't cost you anything but your time. Almost all the information you need is available in the Heavy Maintenance Manual section 74-00-00. Rick ________________________________ Message 2 _____________________________________ Time: 04:04:34 PM PST US From: Dennis Tubbs Subject: Re: RotaxEngines-List: Rough running 912 UL Thanks Hugh for letting us know what it was. I have learned a lot while following your thread, especially now that the problem is solved. On Sep 10, 2016 2:15 PM, "Hugh McKay" wrote: > Gentlemen (bjones,jelling Catz631 h&, Jeff Wemmelring, Bick Girard, > John Hauck, Lowell Fitt, Dee LeBlanc, GHeal, et al) > > Well I found what was causing my rough running engine!! I am some what > embarrassed, but it demonstrates how careful one must be when doing > anything to a Rotax 912 series engine. All this started when I began to > hear excessive engine noise in my head sets when transmitting on my radio .. > Well, if you read my earlier questions regarding the engine noise you wil l > recall that I was advised (good advice)to first check all the grounds. Th is > I did and found no bad grounds. In the course of checking the grounds the re > are two grounding points on the right side of the ignition modules where > two screws screw down into the engine. One of these ground points has two > ground wires attached to it. The other has three ground wires attached. I > removed these grounds, cleaned them and reattached them to their proper > screw location; or I thought I had. Well, after looking carefully at the > top of the engine at these two ground points and feeling all of the wires > in that area I found two loose black wires with a common ring terminal > tucked under the intake manifold on that side of the engine. Well what a > surprise!! Then I began to think, how can that be?? Then I noticed that > these two wires with the common ring terminal exactly fit one of the two > ground points I have just described. I then realized that I had pushed th e > end of this double ground wire with the common ring terminal under the > manifold to get better access to clean the ground point. What I did not > remember when it came time to reattach all the wires was that I had tucke d > this ground wire out of sight. I reattached all the =9Cvisible =9D ground wires > forgetting I had tucked one out of sight. > > Lesson learned! Make sure you know how many wires you have disconnected, > and reconnect the =9Csame=9D number. Anyway, I am back flyin g and the engine > is running fine. Flew down to the big Triple Tree Fly-In just below > Woodruff, SC today with out a problem except the noise in my radio which is > another story. Many thanks for all of your suggestions. I value them and > your willingness to share. > > Regards, > 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 > > *From:* John Hauck > *Sent:* Thursday, September 08, 2016 6:05 PM > *To:* rotaxengines-list@matronics.com > *Subject:* RE: RotaxEngines-List: Rough running 912 UL > > > Might be a good time to replace the connectors.=C3=82 Those have been ra pid > wear parts on my three 912s.=C3=82 They can be bought from Sparkplugs.co m by > getting the part number off of a connector.=C3=82 Price is a quarter wha t > Rotax wants for them. > > > john h > > mkIII > > Burns Junction, Oregon > > > *From:* owner-rotaxengines-list-server@matronics.com [mailto: > owner-rotaxengines-list-server@matronics.com] *On Behalf Of *Richard > Girard > *Sent:* Thursday, September 08, 2016 3:25 PM > *To:* rotaxengines-list@matronics.com > *Subject:* Re: RotaxEngines-List: Rough running 912 UL > > > Hugh, Old mechanics proverb, "90% of carburetor problems are solved in th e > ignition system". That being said, have you checked the resistance of you r > spark plug wires? Since you'll have to re-seat the wires anyway, take the > time to trim each end about 1/4" so that the screw connector has a chance > to seat into fresh, un-corroded wire. Also check the screws themselves fo r > signs of corrosion. Unless the wires are too short afterward this check > won't cost you anything but your time. Almost all the information you nee d > is available in the Heavy Maintenance Manual section 74-00-00. > > > Rick > > ________________________________ Message 3 _____________________________________ Time: 04:10:07 PM PST US From: Richard Girard Subject: Re: RotaxEngines-List: Rough running 912 UL Hugh, Wow! That's great. Always happy to learn of a successful repair, especially one where the price is so right. Now go out there and do some flying. Blue skies, Rick On Sat, Sep 10, 2016 at 4:06 PM, Hugh McKay wrote: > Gentlemen (bjones,jelling Catz631 h&, Jeff Wemmelring, Bick Girard, > John Hauck, Lowell Fitt, Dee LeBlanc, GHeal, et al) > > Well I found what was causing my rough running engine!! I am some what > embarrassed, but it demonstrates how careful one must be when doing > anything to a Rotax 912 series engine. All this started when I began to > hear excessive engine noise in my head sets when transmitting on my radio .. > Well, if you read my earlier questions regarding the engine noise you wil l > recall that I was advised (good advice)to first check all the grounds. Th is > I did and found no bad grounds. In the course of checking the grounds the re > are two grounding points on the right side of the ignition modules where > two screws screw down into the engine. One of these ground points has two > ground wires attached to it. The other has three ground wires attached. I > removed these grounds, cleaned them and reattached them to their proper > screw location; or I thought I had. Well, after looking carefully at the > top of the engine at these two ground points and feeling all of the wires > in that area I found two loose black wires with a common ring terminal > tucked under the intake manifold on that side of the engine. Well what a > surprise!! Then I began to think, how can that be?? Then I noticed that > these two wires with the common ring terminal exactly fit one of the two > ground points I have just described. I then realized that I had pushed th e > end of this double ground wire with the common ring terminal under the > manifold to get better access to clean the ground point. What I did not > remember when it came time to reattach all the wires was that I had tucke d > this ground wire out of sight. I reattached all the =9Cvisible =9D ground wires > forgetting I had tucked one out of sight. > > Lesson learned! Make sure you know how many wires you have disconnected, > and reconnect the =9Csame=9D number. Anyway, I am back flyin g and the engine > is running fine. Flew down to the big Triple Tree Fly-In just below > Woodruff, SC today with out a problem except the noise in my radio which is > another story. Many thanks for all of your suggestions. I value them and > your willingness to share. > > Regards, > 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 > > *From:* John Hauck > *Sent:* Thursday, September 08, 2016 6:05 PM > *To:* rotaxengines-list@matronics.com > *Subject:* RE: RotaxEngines-List: Rough running 912 UL > > > Might be a good time to replace the connectors.=C3=82 Those have been ra pid > wear parts on my three 912s.=C3=82 They can be bought from Sparkplugs.co m by > getting the part number off of a connector.=C3=82 Price is a quarter wha t > Rotax wants for them. > > > john h > > mkIII > > Burns Junction, Oregon > > > *From:* owner-rotaxengines-list-server@matronics.com [mailto: > owner-rotaxengines-list-server@matronics.com] *On Behalf Of *Richard > Girard > *Sent:* Thursday, September 08, 2016 3:25 PM > *To:* rotaxengines-list@matronics.com > *Subject:* Re: RotaxEngines-List: Rough running 912 UL > > > Hugh, Old mechanics proverb, "90% of carburetor problems are solved in th e > ignition system". That being said, have you checked the resistance of you r > spark plug wires? Since you'll have to re-seat the wires anyway, take the > time to trim each end about 1/4" so that the screw connector has a chance > to seat into fresh, un-corroded wire. Also check the screws themselves fo r > signs of corrosion. Unless the wires are too short afterward this check > won't cost you anything but your time. Almost all the information you nee d > is available in the Heavy Maintenance Manual section 74-00-00. > > > Rick > > -- =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx ________________________________ Message 4 _____________________________________ Time: 07:16:54 PM PST US From: Dashwoodlock Subject: Re: RotaxEngines-List: Rough running 912 UL i had a seriouse failure one day. after a short flight i landed. shut down for a couple minutes then took off again for 45min flight. this time engine would not shut down. i was too clos to obsticals so was stuck at idlel til l ground personel could spin me around. i had shut off fuel but at idle she was still running 10 minutes in. turned out i had lost one od the screws that holds aft end of modules on top of engine. so modules were not groundi ng proper. replaced missing fastener and was all good. ------------------------------------------------------------------------------------- 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.