flyrotary@lancaironline.net Mailing List Archive

As a final comment, drilling the rotor housings for thermo-couples pretty much requires it be done with the engine disassembled. I would be very reluctant to try it otherwise. Mark On 8/20/12, Ed Anderson <eanderson@carolina.rr.com> wrote: > Ok, Mark, I get your viewpoint. I can see where temp rise would be detected > > earliest that way and perhaps permit you to throttle back and reduce power > before perhaps damage occurs. Be interesting to see what David ends up > with. > > Ed > > -------------------------------------------------- > From: "Mark Steitle" <msteitle@gmail.com> > Sent: Monday, August 20, 2012 10:15 AM > To: "Rotary motors in aircraft" <flyrotary@lancaironline.net> > Subject: [FlyRotary] Re: EM2 CHT ? > >> Ed, >> >> I think the idea is you'll get a more accurate measurement at the >> combustion surface of each rotor rather than measuring the temp of the >> coolant that has already blended with other coolant in the system. >> Its my understanding that the coolant temp will be higher around the >> plug area than elsewhere, so if you operate near the boiling point of >> your coolant, you would be able to tell it sooner rather than later. >> Still, if you know the safe high-temp limit, it seems you would get a >> better reading off the rotor housing liner than from the coolant. >> >> If you drill/tap each rotor housing you can see how hard each rotor is >> working, similar to EGT's. CHT can serve as a cross-check to EGT. >> >> Also, monitoring cooling system pressure should alert you to an >> imminent boilover event. But you already knew that. ;-) >> >> >> My 2 cents, >> Mark >> >> On 8/20/12, Ed Anderson <eanderson@carolina.rr.com> wrote: >>> I agree, Mark, that your suggestion would probably get you as close to >>> an >>> equivalent CHT as we can get. >>> >>> But, I'm still not understanding what that would usefully provide that >>> is >>> worth more than your coolant temps. >>> >>> I presume that if for some reason the engine temperature were to >>> rapidly >>> increase (perhaps due to detonation or other combustion events) that the >>> >>> CHT >>> reading would provide quicker information on the condition than would >>> the >>> coolant temp so perhaps you could take corrective action before damage. >>> Might be a comfort factor knowing "CHT" if using forced induction on a >>> rotary as things can happen pretty fast when at high boost levels. >>> >>> Ed >>> >>> >>> >>> >>> From: Mark Steitle >>> Sent: Sunday, August 19, 2012 8:48 PM >>> To: Rotary motors in aircraft >>> Subject: [FlyRotary] Re: EM2 CHT ? >>> >>> >>> Seems that this will tell you the coolant temp near the plugs, but not >>> the >>> CHT. If you want to measure the CHT, you'll need to locate a >>> thermo-couple >>> down near the steel liner. You can do this by drilling a small hole >>> down >>> into the web adjacent to the leading plug, stopping at the steel liner. >>> Then insert a thermo-couple down into the hole so that it is touching >>> the >>> steel liner. Now you're reading the temps nearest the combustion >>> chamber, >>> closest thing we have to CHT. >>> >>> >>> Mark >>> >>> >>> On Sun, Aug 19, 2012 at 10:02 AM, <hoursaway1@comcast.net> wrote: >>> >>> Sounds like a plan to me Ed, should have time Sun. to do. David >>> >>> >>> ------------------------------------------------------------------------------ >>> From: "Ed Anderson" <eanderson@carolina.rr.com> >>> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net> >>> Sent: Saturday, August 18, 2012 6:54:35 AM >>> Subject: [FlyRotary] Re: EM2 CHT ? >>> >>> >>> I think I would run the engine at operational rpms (>5000) and watch >>> the >>> coolant/oil temperatures - when they got to my maximum limit, I would >>> check >>> the CHT reading and perhaps add 50 degrees for the limit (to start >>> with). >>> If I got a lot of false alarms at that margin I would try another 50 >>> deg. >>> Just a WAG. >>> >>> Ed >>> >>> >>> From: hoursaway1@comcast.net >>> Sent: Friday, August 17, 2012 10:20 PM >>> To: Rotary motors in aircraft >>> Subject: [FlyRotary] EM2 CHT ? >>> >>> >>> What are we using for high temp numbers from the CHT sensors on the >>> 13B >>> rotary, I have the under the spark plug style sensors bolted to each >>> rotor >>> housing in some factory threaded holes just above the spark plugs, not >>> really the hottest spot but the holes were already in place so I KISSed >>> it & >>> moved on, now I need to set my high temp warning limit & do not know what >>> >>> to >>> use. Possibly do an eng. run with upper cowl off & check bolt/sensor >>> temp >>> with a lazer temp gun at about 4000 RPM & go another 50 deg. higher? >>> Ideas? David R. Cook RV6A Rotary >>> >>> >>> >>> >>> >>> No virus found in this message. >>> Checked by AVG - www.avg.com >>> Version: 2012.0.2197 / Virus Database: 2437/5206 - Release Date: >>> 08/17/12 >>> >>> >>> >>> No virus found in this message. >>> Checked by AVG - www.avg.com >>> Version: 2012.0.2197 / Virus Database: 2437/5211 - Release Date: >>> 08/20/12 >>> >> >> -- >> Homepage: http://www.flyrotary.com/ >> Archive and UnSub: >> http://mail.lancaironline.net:81/lists/flyrotary/List.html >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2012.0.2197 / Virus Database: 2437/5211 - Release Date: 08/20/12 >> > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html >