---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Fri 05/18/12: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:09 AM - Re: 914 starts to surge at 3950 RPM (craig) 2. 05:48 AM - Re: 914 starts to surge at 3950 RPM (Frans Veldman) 3. 11:59 AM - Re: 914 starts to surge at 3950 RPM (Jerry Rehn) ________________________________ Message 1 _____________________________________ Time: 01:09:31 AM PST US From: "craig" Subject: RE: Europa-List: 914 starts to surge at 3950 RPM I'm no expert, but, if memory serves, this problem has been encountered before, I think it was tracked to a bad earth on the ignition modules ________________________________ Message 2 _____________________________________ Time: 05:48:22 AM PST US From: Frans Veldman Subject: Re: Europa-List: 914 starts to surge at 3950 RPM On 05/17/2012 12:36 AM, Robert Borger wrote: > Advance the throttle and it began to surge. Have you tried isolating the waste gate servo from the ECU? Frans ________________________________ Message 3 _____________________________________ Time: 11:59:21 AM PST US Subject: Re: Europa-List: 914 starts to surge at 3950 RPM From: Jerry Rehn I assume you mounted a switch for the servo motor on your panel. It's purpos e is to break the circuit of the servo motor for a short time in case of sur ging of the TCU. Maybe this is your problem? Run the engine and then briefly switch servo switch off and back on. Hopefully it's that simple. It is supp ose to stabilize the surging. Jerry Sent from my iPad On May 16, 2012, at 3:36 PM, Robert Borger wrote: > Friends, > > As many of you know, my Europa has been down for about a year while it was converted it to tri-gear and I rebuilt the instrument panel. We ran the en gine about 2 weeks ago to check the carb balance and idle. Those were OK at the time. I didn't run the engine any further that day because of other co mmitments (preparing for a 2 week trip to SC). Monday, I went out to do a f ull run-up and check of the engine. Started fine, idled OK as long as I hel d the "Choke" out while warming up. After it was warm it idled OK without t he "Choke." Engine nice and smooth. I slowly applied throttle and as it ap proached 4000 RPM it began to surge. Engine RPM dropped to about 3250 and w ould return to almost 4000 then drop down to 3250 and return to almost 4000, repeat, repeat, down/up/down/up/down Below 3950 RPM it ran smooth and fine. Advance the throttle and it began to surge. > > EGTs & CHTs all normal and close to equal. Mag drop at 3900 RPM were almo st equal. The lower plugs always have had a 50-75 RPM greater drop. Turnin g on the boost pump made no difference. Engine has about 25 hrs total time s o far and has run like a sewing machine up to now. > > Any ideas as to the source of the problem? Any suggestions as what to che ck? Could it be the Turbo or Turbo Controller? > > For starters, I guess I need someone to help operate the throttle while I o bserve the turbo controller and wastegate operation. Tommy will probably he lp there. > > Any input would be appreciated. > > Thanks in advance! > > Blue skies & tailwinds, > Bob Borger > Europa XS Tri, Rotax 914, Airmaster C/S Prop. > Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP > 3705 Lynchburg Dr. > Corinth, TX 76208-5331 > Cel: 817-992-1117 > rlborger@mac.com > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message europa-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Europa-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/europa-list Browse Digests http://www.matronics.com/digest/europa-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.