---------------------------------------------------------- RV-List Digest Archive --- Total Messages Posted Fri 06/10/11: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:01 AM - Re: sudden high temps (Dale Ensing) 2. 05:28 AM - RV6A CHT Problem (Jack Haviland) 3. 05:49 AM - Re: RV6A CHT Problem (Kelly McMullen) 4. 06:46 AM - Re: RV6A CHT Problem (Carl Froehlich) 5. 06:54 AM - Re: sudden high temps (thomas sargent) 6. 07:09 AM - Re: RV6A CHT Problem (Mike Robertson) 7. 07:11 AM - Re: sudden high temps (Mike Robertson) 8. 08:44 AM - Re: sudden high temps (Dale Ensing) 9. 09:22 AM - Re: RV6A CHT Problem (Ed Holyoke) 10. 05:43 PM - Re: RV6A CHT Problem (Doug Gray) ________________________________ Message 1 _____________________________________ Time: 03:01:37 AM PST US Subject: Re: RV-List: sudden high temps From: Dale Ensing You can buy pipe cleaners that have small wire bristles mixed in with the so ft fibers. Might be worth a try. I also had similar paint peeling on my Aerosport Power O-360 but no high tem ps that I attribute to it. I used a "chip chaser" tool to clean the loose pa int from the fins. Dale Ensing Sent from my iPad On Jun 10, 2011, at 1:39 AM, thomas sargent wrote: > I've been flying my 6A here in southern AZ since last august. I haven't ha d any heating problems until last week. Cyl. head and oil temps on my Bart L alonde IO-360 were much higher than normal. I carefully inspected everythin g, took off the cowl and cooling plenum. Everything looked OK except that l ooking at the cooling fins from underneath the engine there was a LOT of pee ling paint on them. (This engine has always had peeling paint.) On closer i nspection I found a lot of fins that had a "flap" of paint attached only at t he edge of the fin but laying down flat on the fin's surface. This could co ver a layer of air between the fin and the paint, thus "insulating" it. The flap of paint that isn't laying flat could impede airflow. I called Bart a nd he opined that the peeling paint might be the cause. He advised me to rem ove it and see what happens. > > I spent a couple hours tonight trying to get the loose paint off using den tal picks, tiny brushes, small files. It's difficult because it's hard to r each and the paint is pretty flexible and tough. Has any one else had this p roblem? Is there anything better to clean the paint out with? Something li ke a pipe cleaner but with brass bristles would be just right, I think. Any suggestions? > > -- > Tom Sargent > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 2 _____________________________________ Time: 05:28:25 AM PST US From: Jack Haviland Subject: RV-List: RV6A CHT Problem I'm seeking advice about a CHT issue with a recently completed RV6A with 30 hours on an O-320 D1A ordered from Van's. 1.5 quarts of break-in oil has been consumed during those hours and I'm getting ready to take plane out of service for an oil change etc. Climbing out at 120 knots produces 415 degrees F. CHT temperatures before getting to pattern altitude and cruise at around 65% power produces about 395 degrees (at ambient temperatures of 70-80 degrees F.). Oil temperatures remain below 210 degrees and both CHT and EGT temperatures are reasonably uniform across the four cylinders. Baffling (both above and below the cylinders) has been checked and the inlet area "ramps" are sealed on both the inboard and outboard ends. There is a 60 - 70 degree F. difference in EGT temperature between "full rich" and "leaned until the first cylinder peaks" during tests at 8500' (conducted without wheel pants or strut fairings). There is no fuel flow instrument but fuel pressure readings appear to be highly affected by engine temperature. On the ground it is 5 PSI (without the boost pump) but the drops to 1 PSI or less when the engine is hot. Since the measured cruise and full power CHT values are slightly below Lycoming's "acceptance levels" for an O-320 they (politely) say: 1) they are "unable to help", 2) the engine cannot be considered broken before 50 hours, and 3) high CHT temperatures are usually cause by airflow problems. Van's referred me to Bart in British Columbia who recommends drilling the carb jet .006" oversize. Web search results suggest opening up the lower cowl outlet area via louvres (or simply cutting back the lower cowl) would be helpful. I'd greatly appreciate advice from those who have "been there done that". jack ________________________________ Message 3 _____________________________________ Time: 05:49:37 AM PST US From: Kelly McMullen Subject: Re: RV-List: RV6A CHT Problem If you don't have wheel pants/fairings on, the engine will run hotter, probably 20-30 degrees. Make sure magneto(or equivalent electronic system) timing is spot on. If in doubt, try retarding a couple degrees. Ensure you climb at full throttle. Make sure your throttle cable is taking the carb to the stop. When the throttle is retarded 1/4-1/2 in. the carb power enrichment circuit closes and the engine will run significantly leaner and hotter. Ensure there is at least 1/8" gap between your baffles and cylinder head at front of #2 cyl and rear of #3. If you sealed that area tight, the intake side of the cyl head is not getting cooling because there are very thin to no fins there. Inserting a double thickness strip of baffle seal there to allow airflow will help. They are correct that temps will continue to come down as you get up to 50 hours. Until then be sure to run at least 100 degrees rich of peak EGT. Some of Vans cowlings are marginal in outlet area, but that usually also shows up with high oil temps as well as CHT. I would not have carb main jet drilled. That takes very precision drills. Field drilled jets don't necessarily flow in proportion to expected drilling. If you want to go that route, talk to Tempest(or whatever they are calling the carb company now) and get a new jet of desired size from them. Many carbs have several different jet sizes for different applications. Some 180 hp O-360s have 4 different jet sizes resulting in different 10- numbers where the main jet is the only difference. On 6/10/2011 5:24 AM, Jack Haviland wrote: > --> RV-List message posted by: Jack Haviland > > I'm seeking advice about a CHT issue with a recently completed RV6A with 30 hours on an O-320 D1A ordered from Van's. 1.5 quarts of break-in oil has been consumed during those hours and I'm getting ready to take plane out of service for an oil change etc. > > Climbing out at 120 knots produces 415 degrees F. CHT temperatures before getting to pattern altitude and cruise at around 65% power produces about 395 degrees (at ambient temperatures of 70-80 degrees F.). Oil temperatures remain below 210 degrees and both CHT and EGT temperatures are reasonably uniform across the four cylinders. Baffling (both above and below the cylinders) has been checked and the inlet area "ramps" are sealed on both the inboard and outboard ends. There is a 60 - 70 degree F. difference in EGT temperature between "full rich" and "leaned until the first cylinder peaks" during tests at 8500' (conducted without wheel pants or strut fairings). There is no fuel flow instrument but fuel pressure readings appear to be highly affected by engine temperature. On the ground it is 5 PSI (without the boost pump) but the drops to 1 PSI or less when the engine is hot. > > Since the measured cruise and full power CHT values are slightly below Lycoming's "acceptance levels" for an O-320 they (politely) say: > 1) they are "unable to help", > 2) the engine cannot be considered broken before 50 hours, and > 3) high CHT temperatures are usually cause by airflow problems. > Van's referred me to Bart in British Columbia who recommends drilling the carb jet .006" oversize. Web search results suggest opening up the lower cowl outlet area via louvres (or simply cutting back the lower cowl) would be helpful. > > I'd greatly appreciate advice from those who have "been there done that". > > jack > > ________________________________ Message 4 _____________________________________ Time: 06:46:57 AM PST US From: "Carl Froehlich" Subject: RE: RV-List: RV6A CHT Problem A side note, a recent RV-8 builder with an IO-390 engine noted a measureable drop in temperatures when he shifted from straight weight mineral oil to AeroShell multi-grade after engine break in. If you used only 1.5 quarts over the first 30 hours I'd say your break in is complete. Carl -----Original Message----- From: owner-rv-list-server@matronics.com [mailto:owner-rv-list-server@matronics.com] On Behalf Of Kelly McMullen Sent: Friday, June 10, 2011 8:47 AM Subject: Re: RV-List: RV6A CHT Problem If you don't have wheel pants/fairings on, the engine will run hotter, probably 20-30 degrees. Make sure magneto(or equivalent electronic system) timing is spot on. If in doubt, try retarding a couple degrees. Ensure you climb at full throttle. Make sure your throttle cable is taking the carb to the stop. When the throttle is retarded 1/4-1/2 in. the carb power enrichment circuit closes and the engine will run significantly leaner and hotter. Ensure there is at least 1/8" gap between your baffles and cylinder head at front of #2 cyl and rear of #3. If you sealed that area tight, the intake side of the cyl head is not getting cooling because there are very thin to no fins there. Inserting a double thickness strip of baffle seal there to allow airflow will help. They are correct that temps will continue to come down as you get up to 50 hours. Until then be sure to run at least 100 degrees rich of peak EGT. Some of Vans cowlings are marginal in outlet area, but that usually also shows up with high oil temps as well as CHT. I would not have carb main jet drilled. That takes very precision drills. Field drilled jets don't necessarily flow in proportion to expected drilling. If you want to go that route, talk to Tempest(or whatever they are calling the carb company now) and get a new jet of desired size from them. Many carbs have several different jet sizes for different applications. Some 180 hp O-360s have 4 different jet sizes resulting in different 10- numbers where the main jet is the only difference. On 6/10/2011 5:24 AM, Jack Haviland wrote: > --> RV-List message posted by: Jack Haviland > > I'm seeking advice about a CHT issue with a recently completed RV6A with 30 hours on an O-320 D1A ordered from Van's. 1.5 quarts of break-in oil has been consumed during those hours and I'm getting ready to take plane out of service for an oil change etc. > > Climbing out at 120 knots produces 415 degrees F. CHT temperatures before getting to pattern altitude and cruise at around 65% power produces about 395 degrees (at ambient temperatures of 70-80 degrees F.). Oil temperatures remain below 210 degrees and both CHT and EGT temperatures are reasonably uniform across the four cylinders. Baffling (both above and below the cylinders) has been checked and the inlet area "ramps" are sealed on both the inboard and outboard ends. There is a 60 - 70 degree F. difference in EGT temperature between "full rich" and "leaned until the first cylinder peaks" during tests at 8500' (conducted without wheel pants or strut fairings). There is no fuel flow instrument but fuel pressure readings appear to be highly affected by engine temperature. On the ground it is 5 PSI (without the boost pump) but the drops to 1 PSI or less when the engine is hot. > > Since the measured cruise and full power CHT values are slightly below Lycoming's "acceptance levels" for an O-320 they (politely) say: > 1) they are "unable to help", > 2) the engine cannot be considered broken before 50 hours, and > 3) high CHT temperatures are usually cause by airflow problems. > Van's referred me to Bart in British Columbia who recommends drilling the carb jet .006" oversize. Web search results suggest opening up the lower cowl outlet area via louvres (or simply cutting back the lower cowl) would be helpful. > > I'd greatly appreciate advice from those who have "been there done that". > > jack > > ________________________________ Message 5 _____________________________________ Time: 06:54:51 AM PST US Subject: Re: RV-List: sudden high temps From: thomas sargent Dale: That sounds interesting. Can you suggest where I might get such a thing? On Fri, Jun 10, 2011 at 2:57 AM, Dale Ensing wrote: > You can buy pipe cleaners that have small wire bristles mixed in with the > soft fibers. Might be worth a try. > > -- Tom Sargent ________________________________ Message 6 _____________________________________ Time: 07:09:26 AM PST US From: Mike Robertson Subject: RE: RV-List: RV6A CHT Problem Tom=2C One other suggestion. Have you tried using compressed air to blow out the area as you are trying to clean out everything? Mike Robertson > From: carl.froehlich@verizon.net > To: rv-list@matronics.com > Subject: RE: RV-List: RV6A CHT Problem > Date: Fri=2C 10 Jun 2011 09:42:58 -0400 > et> > > A side note=2C a recent RV-8 builder with an IO-390 engine noted a measur eable > drop in temperatures when he shifted from straight weight mineral oil to > AeroShell multi-grade after engine break in. > > If you used only 1.5 quarts over the first 30 hours I'd say your break in is > complete. > > Carl > > -----Original Message----- > From: owner-rv-list-server@matronics.com > [mailto:owner-rv-list-server@matronics.com] On Behalf Of Kelly McMullen > Sent: Friday=2C June 10=2C 2011 8:47 AM > To: rv-list@matronics.com > Subject: Re: RV-List: RV6A CHT Problem > > > If you don't have wheel pants/fairings on=2C the engine will run hotter =2C > probably 20-30 degrees. Make sure magneto(or equivalent electronic > system) timing is spot on. If in doubt=2C try retarding a couple degrees. > Ensure you climb at full throttle. Make sure your throttle cable is > taking the carb to the stop. When the throttle is retarded 1/4-1/2 in. > the carb power enrichment circuit closes and the engine will run > significantly leaner and hotter. Ensure there is at least 1/8" gap > between your baffles and cylinder head at front of #2 cyl and rear of > #3. If you sealed that area tight=2C the intake side of the cyl head is > not getting cooling because there are very thin to no fins there. > Inserting a double thickness strip of baffle seal there to allow airflow > will help. > They are correct that temps will continue to come down as you get up to > 50 hours. Until then be sure to run at least 100 degrees rich of peak > EGT. Some of Vans cowlings are marginal in outlet area=2C but that usuall y > also shows up with high oil temps as well as CHT. > I would not have carb main jet drilled. That takes very precision > drills. Field drilled jets don't necessarily flow in proportion to > expected drilling. If you want to go that route=2C talk to Tempest(or > whatever they are calling the carb company now) and get a new jet of > desired size from them. Many carbs have several different jet sizes for > different applications. Some 180 hp O-360s have 4 different jet sizes > resulting in different 10- numbers where the main jet is the only > difference. > > > On 6/10/2011 5:24 AM=2C Jack Haviland wrote: > > > > I'm seeking advice about a CHT issue with a recently completed RV6A wit h > 30 hours on an O-320 D1A ordered from Van's. 1.5 quarts of break-in oil h as > been consumed during those hours and I'm getting ready to take plane out of > service for an oil change etc. > > > > Climbing out at 120 knots produces 415 degrees F. CHT temperatures befo re > getting to pattern altitude and cruise at around 65% power produces about > 395 degrees (at ambient temperatures of 70-80 degrees F.). Oil temperatur es > remain below 210 degrees and both CHT and EGT temperatures are reasonably > uniform across the four cylinders. Baffling (both above and below the > cylinders) has been checked and the inlet area "ramps" are sealed on both > the inboard and outboard ends. There is a 60 - 70 degree F. difference in > EGT temperature between "full rich" and "leaned until the first cylinder > peaks" during tests at 8500' (conducted without wheel pants or strut > fairings). There is no fuel flow instrument but fuel pressure readings > appear to be highly affected by engine temperature. On the ground it is 5 > PSI (without the boost pump) but the drops to 1 PSI or less when the engi ne > is hot. > > > > Since the measured cruise and full power CHT values are slightly below > Lycoming's "acceptance levels" for an O-320 they (politely) say: > > 1) they are "unable to help"=2C > > 2) the engine cannot be considered broken before 50 hours=2C and > > 3) high CHT temperatures are usually cause by airflow problems. > > Van's referred me to Bart in British Columbia who recommends drilling t he > carb jet .006" oversize. Web search results suggest opening up the lower > cowl outlet area via louvres (or simply cutting back the lower cowl) woul d > be helpful. > > > > I'd greatly appreciate advice from those who have "been there done that ". > > > > jack > > > > > > > > > > > > > > > =========== =========== =========== =========== > > > ________________________________ Message 7 _____________________________________ Time: 07:11:09 AM PST US From: Mike Robertson Subject: RE: RV-List: sudden high temps Tom=2C Have you tried using compressed air while you are cleaning the paint out? That may help. Mike Robertson Subject: RV-List: sudden high temps From: sarg314@gmail.com I've been flying my 6A here in southern AZ since last august. I haven't had any heating problems until last week. Cyl. head and oil temps on my Bart Lalonde IO-360 were much higher than normal. I carefully inspected everyth ing=2C took off the cowl and cooling plenum. Everything looked OK except t hat looking at the cooling fins from underneath the engine there was a LOT of peeling paint on them. (This engine has always had peeling paint.) On c loser inspection I found a lot of fins that had a "flap" of paint attached only at the edge of the fin but laying down flat on the fin's surface. Thi s could cover a layer of air between the fin and the paint=2C thus "insulat ing" it. The flap of paint that isn't laying flat could impede airflow. I called Bart and he opined that the peeling paint might be the cause. He ad vised me to remove it and see what happens. I spent a couple hours tonight trying to get the loose paint off using dent al picks=2C tiny brushes=2C small files. It's difficult because it's hard to reach and the paint is pretty flexible and tough. Has any one else had this problem? Is there anything better to clean the paint out with? Somet hing like a pipe cleaner but with brass bristles would be just right=2C I t hink. Any suggestions? -- Tom Sargent ________________________________ Message 8 _____________________________________ Time: 08:44:18 AM PST US From: "Dale Ensing" Subject: Re: RV-List: sudden high temps If I remember correctly Tom, I purchased them at a tobacco/pipe shop. Dale ----- Original Message ----- From: thomas sargent To: rv-list@matronics.com Sent: Friday, June 10, 2011 9:52 AM Subject: Re: RV-List: sudden high temps Dale: That sounds interesting. Can you suggest where I might get such a thing? On Fri, Jun 10, 2011 at 2:57 AM, Dale Ensing wr ote: You can buy pipe cleaners that have small wire bristles mixed in with t he soft fibers. Might be worth a try. -- Tom Sargent ________________________________ Message 9 _____________________________________ Time: 09:22:40 AM PST US From: Ed Holyoke Subject: Re: RV-List: RV6A CHT Problem 415 to patten altitude? That's real hot, real fast. Do I read you to say that EGT on any given cylinder only spans 60 degrees from rich to lean? I'd expect to see a couple hundred, maybe more. Too bad you don't have a fuel flow. Sounds like you are lean. Check for full travel on both the mixture and throttle arms. If they are both on the stops, your main jet is probably too small. I wouldn't worry about the 1 psi fuel pressure, hot. Just run the boost pump for a few minutes after takeoff and the pressure will eventually come up as it moves more cool fuel into the carb. Pax, Ed Holyoke On 6/10/2011 5:24 AM, Jack Haviland wrote: > --> RV-List message posted by: Jack Haviland > > I'm seeking advice about a CHT issue with a recently completed RV6A with 30 hours on an O-320 D1A ordered from Van's. 1.5 quarts of break-in oil has been consumed during those hours and I'm getting ready to take plane out of service for an oil change etc. > > Climbing out at 120 knots produces 415 degrees F. CHT temperatures before getting to pattern altitude and cruise at around 65% power produces about 395 degrees (at ambient temperatures of 70-80 degrees F.). Oil temperatures remain below 210 degrees and both CHT and EGT temperatures are reasonably uniform across the four cylinders. Baffling (both above and below the cylinders) has been checked and the inlet area "ramps" are sealed on both the inboard and outboard ends. There is a 60 - 70 degree F. difference in EGT temperature between "full rich" and "leaned until the first cylinder peaks" during tests at 8500' (conducted without wheel pants or strut fairings). There is no fuel flow instrument but fuel pressure readings appear to be highly affected by engine temperature. On the ground it is 5 PSI (without the boost pump) but the drops to 1 PSI or less when the engine is hot. > > Since the measured cruise and full power CHT values are slightly below Lycoming's "acceptance levels" for an O-320 they (politely) say: > 1) they are "unable to help", > 2) the engine cannot be considered broken before 50 hours, and > 3) high CHT temperatures are usually cause by airflow problems. > Van's referred me to Bart in British Columbia who recommends drilling the carb jet .006" oversize. Web search results suggest opening up the lower cowl outlet area via louvres (or simply cutting back the lower cowl) would be helpful. > > I'd greatly appreciate advice from those who have "been there done that". > > jack > > ________________________________ Message 10 ____________________________________ Time: 05:43:16 PM PST US Subject: Re: RV-List: RV6A CHT Problem From: Doug Gray On Fri, 2011-06-10 at 08:24 -0400, Jack Haviland wrote: > 3) high CHT temperatures are usually cause by airflow problems. > My experience paralleled yours almost exactly (same engine RV6 sens prop) except my CHT remained below 400 at a 120 knot climb. This was fine except after holding for traffic on the ground for an extended period. In cruise the temps dropped to 333 341 372 367. I thought my baffle seals were fine because they were wide and fit the cowling well. Except: I hand tried to minimise the number of breaks in the fabric obviously to 'improve' the seal. But what I ended up doing was causing some MINOR puckering away from the cowl surface at the reverse bends in 4 places. Above the inlet ramps and above the rear cylinders. I expected air pressure would force these puckers against the cowling. I was thinking that perhaps during climb the increased angle of attack air at the puckers above the inlet ramps was causing the front seals to flip down and allow air to escape past the seal, then in cruise the seal fabric would settle back where it should be.. Only several weeks ago I was determined to solve the issue and drastic action was necessary so I popped the cowling off and slit the material at these puckers to allow them to lay flat flat on the cowling. The test flight following this surgery I was able to climb full power to 6500 at about 90 knots and the temps remained below 400. In cruise the temps dropped to 325 342 360 357, ie about 10 degree drop all round. Also my oil temp dropped (another!) 8 degrees. I am happy with the change. Possibly I need a deflector on cyl 1 to even the temps between 1 and 3. Good luck, Doug Gray ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV-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/rv-list Browse Digests http://www.matronics.com/digest/rv-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.