---------------------------------------------------------- Kitfox-List Digest Archive --- Total Messages Posted Thu 05/29/14: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:11 AM - 582 static rpm (Patrick Reilly) 2. 08:15 AM - Re: 582 breakin (mikeperkins) 3. 08:16 AM - Re: 582 static rpm (mikeperkins) 4. 01:28 PM - Re: Re: 582 static rpm (Patrick Reilly) 5. 02:02 PM - Re: Re: 582 static rpm (Guy Buchanan) 6. 02:31 PM - Re: 582 static rpm (mikeperkins) 7. 02:51 PM - Re: Re: 582 static rpm (Patrick Reilly) 8. 02:57 PM - Re: Re: 582 static rpm (Patrick Reilly) ________________________________ Message 1 _____________________________________ Time: 07:11:40 AM PST US Subject: Kitfox-List: 582 static rpm From: Patrick Reilly Hey Dave Fischer are you still out there? What should static rpm on a 582 with a 72" Warp Drive prop be? Would appreciate any other info on that set up also. -- Pat Reilly Mod 3 582 Rebuild Rockford,IL ________________________________ Message 2 _____________________________________ Time: 08:15:40 AM PST US Subject: Kitfox-List: Re: 582 breakin From: "mikeperkins" Hi Pat, Jared and I talked the other day offline. I mentioned my 532 static RPM was about 5800. But what I was shooting for was a Vx climb of 6600 RPM. When I finally got that, my static speed was 5800 RPM. But when I had a new crankshaft installed, along with the necessary seals and re-timed, I was getting only 4200 or so. The certified rebuilder's recommendation was to reduce the pitch because I had a "new" engine. I thought he was crazy because I was already convinced he'd screwed something up. But in fact by taking some pitch off the prop, I got back to about 6000 static. I'm also getting 6800 RPM on a Vx climb instead of 6600. So I probably need to add back in about 1/4 degree to get back 6600 again. But my overall performance numbers are close to what they were before the rebuild, so I'm not worried that I lost horsepower when it was rebuilt. Rather, the torque/RPM curve probably just moved somewhat. The one thing I've used as a rule is to not run my engine at high power until the coolant temp stabilizes. I don't exceed 3000 RPM until it does. The cylinder bores on the Rotax 2-strokes are round but the pistons are cam-ground, eccentric by about .010". That compensates for the cylinders' uneven expansion when everything heats up to operating temp. But at lower temperatures, the piston/cylinder clearances are not correct, and that often leads to scored pistons, which eventually leads to cold seizures. Following that rule has been pretty good for my engine; the pistons and cylinders are still looking good after 385 hours. I get the feeling that the big oil debate comes down to something else - full warm-ups prior to full power, getting the prop load matched to the engine, and watching the EGTs. (What I mean by matching the prop load to the engine is to get max RPM at max throttle in a Vx or Vy climb, your choice.) It's still possible in my airplane to exceed the 1200 degree EGT limit. I find that if I'm in a cruise descent with low power, say 30 percent, my EGTs soar. When I see that, I pull up to load the engine again and add a little power. Nothing brings the EGTs down quicker than that. It screws up my descent profile, but it helps the engine. The max RPM for a 582 is listed as 6800 (for 5 minutes), whereas my 532 is 6600. So your numbers will be different than mine. But I think the principles are the same. Good seeing you here again, Pat. Hope things are well with you. -------- Mike Perkins Havana, Illinois Model I, 532, B gearbox, GSC prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423968#423968 ________________________________ Message 3 _____________________________________ Time: 08:16:16 AM PST US Subject: Kitfox-List: Re: 582 static rpm From: "mikeperkins" Hi Pat, Jared and I talked the other day offline. I mentioned my 532 static RPM was about 5800. But what I was shooting for was a Vx climb of 6600 RPM. When I finally got that, my static speed was 5800 RPM. But when I had a new crankshaft installed, along with the necessary seals and re-timed, I was getting only 4200 or so. The certified rebuilder's recommendation was to reduce the pitch because I had a "new" engine. I thought he was crazy because I was already convinced he'd screwed something up. But in fact by taking some pitch off the prop, I got back to about 6000 static. I'm also getting 6800 RPM on a Vx climb instead of 6600. So I probably need to add back in about 1/4 degree to get back 6600 again. But my overall performance numbers are close to what they were before the rebuild, so I'm not worried that I lost horsepower when it was rebuilt. Rather, the torque/RPM curve probably just moved somewhat. The one thing I've used as a rule is to not run my engine at high power until the coolant temp stabilizes. I don't exceed 3000 RPM until it does. The cylinder bores on the Rotax 2-strokes are round but the pistons are cam-ground, eccentric by about .010". That compensates for the cylinders' uneven expansion when everything heats up to operating temp. But at lower temperatures, the piston/cylinder clearances are not correct, and that often leads to scored pistons, which eventually leads to cold seizures. Following that rule has been pretty good for my engine; the pistons and cylinders are still looking good after 385 hours. I get the feeling that the big oil debate comes down to something else - full warm-ups prior to full power, getting the prop load matched to the engine, and watching the EGTs. (What I mean by matching the prop load to the engine is to get max RPM at max throttle in a Vx or Vy climb, your choice.) It's still possible in my airplane to exceed the 1200 degree EGT limit. I find that if I'm in a cruise descent with low power, say 30 percent, my EGTs soar. When I see that, I pull up to load the engine again and add a little power. Nothing brings the EGTs down quicker than that. It screws up my descent profile, but it helps the engine. The max RPM for a 582 is listed as 6800 (for 5 minutes), whereas my 532 is 6600. So your numbers will be different than mine. But I think the principles are the same. Good seeing you here again, Pat. Hope things are well with you. -------- Mike Perkins Havana, Illinois Model I, 532, B gearbox, GSC prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423969#423969 ________________________________ Message 4 _____________________________________ Time: 01:28:47 PM PST US Subject: Re: Kitfox-List: Re: 582 static rpm From: Patrick Reilly Mike, Thanks for the quick reply and info. I took the Kitfox out today with 12 1/2 decrees of pitch on the Warp Drive prop. Same setting as yesterday with 5500rpm static (plane tied down). All I could get on a full throttle take off taxi was 4800rpm. Needless to say I didn't takeoff. I'm frustrated now with these different results 2 days in a row with identical prop setting. Plugs look good with rear plugs slightly blacker than front cyl. Guess I'll do a compression check next. I think it has to be carb related problem. Pat Reilly Mod 3 582 Rebuilt Rockford, IL On Thu, May 29, 2014 at 10:13 AM, mikeperkins wrote: > > Hi Pat, > > Jared and I talked the other day offline. I mentioned my 532 static RPM > was about 5800. But what I was shooting for was a Vx climb of 6600 RPM. > When I finally got that, my static speed was 5800 RPM. But when I had a new > crankshaft installed, along with the necessary seals and re-timed, I was > getting only 4200 or so. The certified rebuilder's recommendation was to > reduce the pitch because I had a "new" engine. I thought he was crazy > because I was already convinced he'd screwed something up. But in fact by > taking some pitch off the prop, I got back to about 6000 static. I'm also > getting 6800 RPM on a Vx climb instead of 6600. So I probably need to add > back in about 1/4 degree to get back 6600 again. But my overall performance > numbers are close to what they were before the rebuild, so I'm not worried > that I lost horsepower when it was rebuilt. Rather, the torque/RPM curve > probably just moved somewhat. > > The one thing I've used as a rule is to not run my engine at high power > until the coolant temp stabilizes. I don't exceed 3000 RPM until it does. > The cylinder bores on the Rotax 2-strokes are round but the pistons are > cam-ground, eccentric by about .010". That compensates for the cylinders' > uneven expansion when everything heats up to operating temp. But at lower > temperatures, the piston/cylinder clearances are not correct, and that > often leads to scored pistons, which eventually leads to cold seizures. > Following that rule has been pretty good for my engine; the pistons and > cylinders are still looking good after 385 hours. I get the feeling that > the big oil debate comes down to something else - full warm-ups prior to > full power, getting the prop load matched to the engine, and watching the > EGTs. (What I mean by matching the prop load to the engine is to get max > RPM at max throttle in a Vx or Vy climb, your choice.) > > It's still possible in my airplane to exceed the 1200 degree EGT limit. I > find that if I'm in a cruise descent with low power, say 30 percent, my > EGTs soar. When I see that, I pull up to load the engine again and add a > little power. Nothing brings the EGTs down quicker than that. It screws up > my descent profile, but it helps the engine. > > The max RPM for a 582 is listed as 6800 (for 5 minutes), whereas my 532 is > 6600. So your numbers will be different than mine. But I think the > principles are the same. > > Good seeing you here again, Pat. Hope things are well with you. > > -------- > Mike Perkins > Havana, Illinois > Model I, 532, B gearbox, GSC prop > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=423969#423969 > > -- Pat Reilly Mod 3 582 Rebuild Rockford,IL ________________________________ Message 5 _____________________________________ Time: 02:02:34 PM PST US From: Guy Buchanan Subject: Re: Kitfox-List: Re: 582 static rpm I had a weird thing happen on the old 582 a while ago. I thought my peak RPM was a little high so I added a little pitch, probably 1/2 degree or so. (Long time past.) My static RPM was about the same, but when I hammered it on the runway, the initial RPM was high, but then the prop seemed to "hook-up", the RPM dropped to about 4500 and I couldn't get going. I had to abort the takeoff. I tried a few times and got the same result. (I'd say the prop hooked up at 10-20 knots ground speed.) I went back, pulled out the increased pitch, and everything was fine. My unofficial guess what that the prop was partially stalled static, then un-stalled when I got rolling. I thought that spectacularly unlikely, but could think of no other reason. Oh yes: Warp Drive tapered. Guy Buchanan Ramona, CA Kitfox IV-1200 / 912-S / Warp 3cs / 500 hrs. and grounded Now a glider pilot, too. On 5/29/2014 1:25 PM, Patrick Reilly wrote: > Mike, Thanks for the quick reply and info. I took the Kitfox out today > with 12 1/2 decrees of pitch on the Warp Drive prop. Same setting as > yesterday with 5500rpm static (plane tied down). All I could get on a > full throttle take off taxi was 4800rpm. Needless to say I didn't > takeoff. I'm frustrated now with these different results 2 days in a > row with identical prop setting. Plugs look good with rear plugs > slightly blacker than front cyl. Guess I'll do a compression check > next. I think it has to be carb related problem. > > Pat Reilly > Mod 3 582 Rebuilt > Rockford, IL > > > On Thu, May 29, 2014 at 10:13 AM, mikeperkins > wrote: > > > > > Hi Pat, > > Jared and I talked the other day offline. I mentioned my 532 > static RPM was about 5800. But what I was shooting for was a Vx > climb of 6600 RPM. When I finally got that, my static speed was > 5800 RPM. But when I had a new crankshaft installed, along with > the necessary seals and re-timed, I was getting only 4200 or so. > The certified rebuilder's recommendation was to reduce the pitch > because I had a "new" engine. I thought he was crazy because I was > already convinced he'd screwed something up. But in fact by taking > some pitch off the prop, I got back to about 6000 static. I'm also > getting 6800 RPM on a Vx climb instead of 6600. So I probably need > to add back in about 1/4 degree to get back 6600 again. But my > overall performance numbers are close to what they were before the > rebuild, so I'm not worried that I lost horsepower when it was > rebuilt. Rather, the torque/RPM curve probably just moved somewhat. > > The one thing I've used as a rule is to not run my engine at high > power until the coolant temp stabilizes. I don't exceed 3000 RPM > until it does. The cylinder bores on the Rotax 2-strokes are round > but the pistons are cam-ground, eccentric by about .010". That > compensates for the cylinders' uneven expansion when everything > heats up to operating temp. But at lower temperatures, the > piston/cylinder clearances are not correct, and that often leads > to scored pistons, which eventually leads to cold seizures. > Following that rule has been pretty good for my engine; the > pistons and cylinders are still looking good after 385 hours. I > get the feeling that the big oil debate comes down to something > else - full warm-ups prior to full power, getting the prop load > matched to the engine, and watching the EGTs. (What I mean by > matching the prop load to the engine is to get max RPM at max > throttle in a Vx or Vy climb, your choice.) > > It's still possible in my airplane to exceed the 1200 degree EGT > limit. I find that if I'm in a cruise descent with low power, say > 30 percent, my EGTs soar. When I see that, I pull up to load the > engine again and add a little power. Nothing brings the EGTs down > quicker than that. It screws up my descent profile, but it helps > the engine. > > The max RPM for a 582 is listed as 6800 (for 5 minutes), whereas > my 532 is 6600. So your numbers will be different than mine. But I > think the principles are the same. > > Good seeing you here again, Pat. Hope things are well with you. > > -------- > Mike Perkins > Havana, Illinois > Model I, 532, B gearbox, GSC prop > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=423969#423969 > > > ========== > st" target="_blank">http://www.matronics.com/Navigator?Kitfox-List > ========== > MS - > k">http://forums.matronics.com > ========== > e - > -Matt Dralle, List Admin. > t="_blank">http://www.matronics.com/contribution > ========== > > > -- > Pat Reilly > Mod 3 582 Rebuild > Rockford,IL > * > > > * ________________________________ Message 6 _____________________________________ Time: 02:31:30 PM PST US Subject: Kitfox-List: Re: 582 static rpm From: "mikeperkins" Hi Guy, The symptom you described is very much like the problem I was having when my prop was pitched to coarsely. My guess is that when you put on that extra 1/2 degree, the required prop torque exceeded the engine's available torque. I just posted here to Pat, and you might find that post useful, too. Call anytime. I'm an engineer, and I've stared at the graph in the 3 UL 89-E Rotax bulletin for an hour and still have trouble with it. But the key for me was understanding that when the prop torque is higher than the engine's available torque, the RPM goes screwy. Mike -------- Mike Perkins Havana, Illinois Model I, 532, B gearbox, GSC prop Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423990#423990 ________________________________ Message 7 _____________________________________ Time: 02:51:02 PM PST US Subject: Re: Kitfox-List: Re: 582 static rpm From: Patrick Reilly Mike, Thanks I'll tackle it tomorrow. Pat On Thu, May 29, 2014 at 4:27 PM, mikeperkins wrote: > > Hi Guy, > > The symptom you described is very much like the problem I was having when > my prop was pitched to coarsely. My guess is that when you put on that > extra 1/2 degree, the required prop torque exceeded the engine's available > torque. > > I just posted here to Pat, and you might find that post useful, too. Call > anytime. > > I'm an engineer, and I've stared at the graph in the 3 UL 89-E Rotax > bulletin for an hour and still have trouble with it. But the key for me was > understanding that when the prop torque is higher than the engine's > available torque, the RPM goes screwy. > > Mike > > -------- > Mike Perkins > Havana, Illinois > Model I, 532, B gearbox, GSC prop > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=423990#423990 > > -- Pat Reilly Mod 3 582 Rebuild Rockford,IL ________________________________ Message 8 _____________________________________ Time: 02:57:57 PM PST US Subject: Re: Kitfox-List: Re: 582 static rpm From: Patrick Reilly Guy, Thanks for the info. I'm going to do a compression check. If that is OK, I guess I'll reduce pitch before I tear into anything else. I'm famous for starting with the most complicated thing first. Pitch will be the easiest this time. The engine sure seems to run fine at the lower rpms. Pat Reilly On Thu, May 29, 2014 at 3:59 PM, Guy Buchanan wrote: > I had a weird thing happen on the old 582 a while ago. I thought my peak > RPM was a little high so I added a little pitch, probably 1/2 degree or > so. (Long time past.) My static RPM was about the same, but when I hammered > it on the runway, the initial RPM was high, but then the prop seemed to > "hook-up", the RPM dropped to about 4500 and I couldn't get going. I had to > abort the takeoff. I tried a few times and got the same result. (I'd say > the prop hooked up at 10-20 knots ground speed.) I went back, pulled out > the increased pitch, and everything was fine. My unofficial guess what that > the prop was partially stalled static, then un-stalled when I got rolling. > I thought that spectacularly unlikely, but could think of no other reason. > Oh yes: Warp Drive tapered. > > Guy Buchanan > Ramona, CA > Kitfox IV-1200 / 912-S / Warp 3cs / 500 hrs. and grounded > Now a glider pilot, too. > > On 5/29/2014 1:25 PM, Patrick Reilly wrote: > > Mike, Thanks for the quick reply and info. I took the Kitfox out today > with 12 1/2 decrees of pitch on the Warp Drive prop. Same setting as > yesterday with 5500rpm static (plane tied down). All I could get on a full > throttle take off taxi was 4800rpm. Needless to say I didn't takeoff. I'm > frustrated now with these different results 2 days in a row with identical > prop setting. Plugs look good with rear plugs slightly blacker than front > cyl. Guess I'll do a compression check next. I think it has to be carb > related problem. > > Pat Reilly > Mod 3 582 Rebuilt > Rockford, IL > > > On Thu, May 29, 2014 at 10:13 AM, mikeperkins > wrote: > >> >> Hi Pat, >> >> Jared and I talked the other day offline. I mentioned my 532 static RPM >> was about 5800. But what I was shooting for was a Vx climb of 6600 RPM. >> When I finally got that, my static speed was 5800 RPM. But when I had a new >> crankshaft installed, along with the necessary seals and re-timed, I was >> getting only 4200 or so. The certified rebuilder's recommendation was to >> reduce the pitch because I had a "new" engine. I thought he was crazy >> because I was already convinced he'd screwed something up. But in fact by >> taking some pitch off the prop, I got back to about 6000 static. I'm also >> getting 6800 RPM on a Vx climb instead of 6600. So I probably need to add >> back in about 1/4 degree to get back 6600 again. But my overall performance >> numbers are close to what they were before the rebuild, so I'm not worried >> that I lost horsepower when it was rebuilt. Rather, the torque/RPM curve >> probably just moved somewhat. >> >> The one thing I've used as a rule is to not run my engine at high power >> until the coolant temp stabilizes. I don't exceed 3000 RPM until it does. >> The cylinder bores on the Rotax 2-strokes are round but the pistons are >> cam-ground, eccentric by about .010". That compensates for the cylinders' >> uneven expansion when everything heats up to operating temp. But at lower >> temperatures, the piston/cylinder clearances are not correct, and that >> often leads to scored pistons, which eventually leads to cold seizures. >> Following that rule has been pretty good for my engine; the pistons and >> cylinders are still looking good after 385 hours. I get the feeling that >> the big oil debate comes down to something else - full warm-ups prior to >> full power, getting the prop load matched to the engine, and watching the >> EGTs. (What I mean by matching the prop load to the engine is to get max >> RPM at max throttle in a Vx or Vy climb, your choice.) >> >> It's still possible in my airplane to exceed the 1200 degree EGT limit. I >> find that if I'm in a cruise descent with low power, say 30 percent, my >> EGTs soar. When I see that, I pull up to load the engine again and add a >> little power. Nothing brings the EGTs down quicker than that. It screws up >> my descent profile, but it helps the engine. >> >> The max RPM for a 582 is listed as 6800 (for 5 minutes), whereas my 532 >> is 6600. So your numbers will be different than mine. But I think the >> principles are the same. >> >> Good seeing you here again, Pat. Hope things are well with you. >> >> -------- >> Mike Perkins >> Havana, Illinois >> Model I, 532, B gearbox, GSC prop >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=423969#423969 >> >> >> >> >> >> >> >> ========== >> st" target="_blank">http://www.matronics.com/Navigator?Kitfox-List >> ========== >> MS - >> k">http://forums.matronics.com >> ========== >> e - >> -Matt Dralle, List Admin. >> t="_blank">http://www.matronics.com/contribution >> ========== >> >> >> >> > > > -- > Pat Reilly > Mod 3 582 Rebuild > Rockford,IL > > > * > > > * > > -- Pat Reilly Mod 3 582 Rebuild Rockford,IL ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kitfox-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kitfox-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/kitfox-list Browse Digests http://www.matronics.com/digest/kitfox-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.