---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Thu 12/14/06: 21 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:00 AM - Re: engine replacement time (possums) 2. 07:56 AM - Re: engine replacement time (ElleryWeld@aol.com) 3. 08:24 AM - Any suggestion for a good cleaning of a 912ul? (John Bickham) 4. 08:28 AM - Re: engine replacement time (David Lehman) 5. 09:22 AM - Re: Carb heat (Thom Riddle) 6. 09:45 AM - Re: Overhaulin' (Thom Riddle) 7. 11:03 AM - Re: Overhaulin' (Herb Gayheart) 8. 11:22 AM - Re: engine replacement time (ElleryWeld@AOL.COM) 9. 12:56 PM - Re: Overhaulin' (John Hauck) 10. 01:52 PM - Kolb Trailer Update (Richard & Martha Neilsen) 11. 02:07 PM - Re: Overhaulin' (Jack B. Hart) 12. 03:38 PM - Re: Kolb Trailer Update (N27SB@AOL.COM) 13. 03:58 PM - Re: Kolb Trailer Update (Larry Bourne) 14. 05:02 PM - Ricks trailer/cowl update (Craig Nelson) 15. 05:41 PM - Re: Kolb Trailer Update (Richard & Martha Neilsen) 16. 05:58 PM - Re: Kolb Trailer Update (Dana Hague) 17. 08:23 PM - Re: Kolb Trailer Update (Larry Cottrell) 18. 08:41 PM - Re: Kolb Trailer Update (Richard Girard) 19. 08:47 PM - Re: Any suggestion for a good cleaning of a 912ul? (Richard Girard) 20. 08:51 PM - Re: Overhaulin' (Richard Pike) 21. 10:08 PM - Hirth and Rotax a comparison (Herb Gayheart) ________________________________ Message 1 _____________________________________ Time: 04:00:40 AM PST US From: possums Subject: Re: Kolb-List:engine replacement time >What is the normal engine replacement that others are getting and on >what engines? > >Ellery Original Firestar >do not archive >Since the time has been put on yours fast - (100 hrs per yr.), you >have been able to go that long, >but even engines that get time fast like that are likely to need >at least some attention by 500. >Tom Olenik Olenik Aviation I think the biggest thing that you can do is run your engine every week - if you can. Even if it is only for 15 minutes sitting on the ground - run it up some! I know, if you fold your wings, you can't, but the worst thing you could do is store it without properly preparing it for storage. If it sits there for months or even weeks with the muffler unplugged and the air filter uncovered (they make covers) then the crankshaft is going to get some corrosion/rust on the bearings. 50 hours during the summer & 10 hours during the winter ain't going to do it. Again, not to belabor the point - but I think 706 hrs without a decarb, never had the jugs off - I check the inside with a dental mirror and flashlight thru the plug holes - muffler and carbs off (no carbon to mention) Wallmart oil "or whatever oil you're religion allows you to use". Every 100 hours - check the compression (still 120 - just like it came out of the box) rings aren't stuck etc. I'll probably get 800 hrs outa this thing, maybe 900? That's what they're getting overseas. I do change the plugs every 25 hrs - the expensive plugs - whatever that's worth. Maybe I just got a good engine, who knows? I've had others back in the 90's that we decarboned every 50 hours (447s), and all that did was f--k them up. They never line back up exactly like you took them apart, even with the right tools. The pistons never seat like they did before you "fixed" it. I've been breaking these things since 1983. BTW - I'm not an engine guy - I just barely understand how these things work, but I figure I got about 38,000 miles on the one I got now ,,,not bad for a 7 year old $4,400 UL engine. Around the world 1 1/2 times - right?? Most of my time is local, around at 4,400 to 6,000 RPM. I do some trips now and again (Not like John H) , but I like to fly slow and low. These things are like motorcycles - with wings - not cars. I don't want to climb Mt. Everest, I don't want to drive from Georgia to California - been there done that. http://video.google.com/videoplay?docid=-4742969166825363751&hl=en When It's Time To Decarbon?? http://www.800-airwolf.com/pdffiles/ARTICLES/part47.pdf ________________________________ Message 2 _____________________________________ Time: 07:56:50 AM PST US From: ElleryWeld@aol.com Subject: Re: Kolb-List:engine replacement time Thanks for the info mabe I should just re install my old engine and finish wearing it out Ellery do not archive ________________________________ Message 3 _____________________________________ Time: 08:24:02 AM PST US Subject: Kolb-List: Any suggestion for a good cleaning of a 912ul? From: "John Bickham" Hello List, Getting closer. Finally finished painting Tuesday. Ready to put engine on airframe. Need to give it a good cleaning. Easy to do now while on bench. Appendix D (a) Each person performing an annual or 100-hour inspection shall, before that inspection, remove or open all necessary inspection plates, access doors, fairing, and cowling. He shall thoroughly clean the aircraft and aircraft engine. Any suggestions on what to use (or not to use)? Some of the aluminum is a little weathered and has a slight white crust (alum corrosion). -------- Thanks too much, John Bickham Mark III-C "Using my Repairman Certificate" St. Francisville, LA Do Not Archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=81509#81509 ________________________________ Message 4 _____________________________________ Time: 08:28:47 AM PST US From: "David Lehman" Subject: Re: Kolb-List:engine replacement time Ellery... Did you ever get your floats installed?... Like it's the right time of year, not... If you did, give us some pictures... DVD On 12/14/06, ElleryWeld@aol.com wrote: > > *Thanks for the info mabe I should just re install my old engine and > finish wearing it out > > Ellery > do not archive* ________________________________ Message 5 _____________________________________ Time: 09:22:36 AM PST US From: Thom Riddle Subject: Re: Kolb-List: Carb heat Richard, That is a good treatment of the subject of carb icing and I'm glad you posted it. BUT, the folks who wrote that are temperature math challenged. In their table of temperature changes they have made some serious errors in converting temperature CHANGE from C to F. Temperature CHANGE (is not the same as actual temperature) Their Conversion Correct Conversion 20C 68F 36F 30C 86F 54F 83C 181F 149F 140C 284F 252C Yes, on your dual scale thermometer, 20C = 68F, 30C=86F, 83C=181F, and 140C=284F but the formula for temperature CHANGE, not temperature scale equivalents is a simple linear relationship. A change of 10 degrees C is equal to a change of 18 degrees F. To convert ACTUAL temps from C to F the formula is slightly more complex. degrees C x 1.8 + 32 = degrees F examples 0C (water freezing) x 1.8 + 32 = 32 F (water freezing) 100C (water boiling) x 1.8 + 32 = 212 F (water boiling) To convert temp CHANGE in C to temperature CHANGE in F, the formula is change in C x 1.8 = change in F example temp change of -20C x 1.8 = -36F I can't even remember how many times this simple error has occurred in official documentation from otherwise technically savvy organizations, but it is way too many and something a technical editor should easily find and correct before publication. Thom in Buffalo ________________________________ Message 6 _____________________________________ Time: 09:45:01 AM PST US From: Thom Riddle Subject: Re: Kolb-List: Overhaulin' .....Can someone explain to me why it is Rotax can't make 2-stroke bearings and/or crankshaft components that last longer than 300 hours (notwithstanding those that go well over that time limit)? I mean, is it a matter of cost/materials, or is it a "no material known to man can withstand the stresses involved" kind of thing?..... In addition to what John Hauck said, I would add the following. If my memory serves me correctly, the forces acting on reciprocating machine parts is proportional to the 4th power of the RPM. Jack Hart can probably confirm or correct this number. In other words, if the RPM goes up from 3000 to 6000 (doubling) then the reciprocating forces go up by a factor of 16 (2 to the 4th power). So, if a 2 stroke engine normally runs at 6,000 rpm vs a 912 running at 5,000 rpm, the 2-stroker is running 20% faster in rpm which (if all other variables were held constant) would equate to a bit over twice the forces (1.2 ^ 4 = 2.076). Any wonder why drag racing engines running at redline for a 1/4 mile need rebuilding so frequently? When I was flying an early FIrestar with 377 I normally cruised at around 5200 rpm. No signs of trouble at all with that engine at near 500 hours on it when I sold the airplane. Thom in Buffalo do not archive ________________________________ Message 7 _____________________________________ Time: 11:03:58 AM PST US Subject: Re: Kolb-List: Overhaulin' From: Herb Gayheart The lower rpms of the Hirth engines might account for some of their stated 1000 hour overhaul? Herb On Thu, 14 Dec 2006 12:44:08 -0500 Thom Riddle writes: > > .....Can someone explain to me why it is Rotax can't make 2-stroke > bearings > and/or crankshaft components that last longer than 300 hours > (notwithstanding those that go well over that time limit)? I > > mean, is > it a matter of cost/materials, or is it a "no material known > to > man > can withstand the stresses involved" kind of thing?..... > > In addition to what John Hauck said, I would add the following. If > my > memory serves me correctly, the forces acting on reciprocating > machine > parts is proportional to the 4th power of the RPM. Jack Hart can > probably confirm or correct this number. In other words, if the RPM > > goes up from 3000 to 6000 (doubling) then the reciprocating forces > go > up by a factor of 16 (2 to the 4th power). So, if a 2 stroke engine > > normally runs at 6,000 rpm vs a 912 running at 5,000 rpm, the > 2-stroker > is running 20% faster in rpm which (if all other variables were held > > constant) would equate to a bit over twice the forces (1.2 ^ 4 = > 2.076). Any wonder why drag racing engines running at redline for a > 1/4 > mile need rebuilding so frequently? > > When I was flying an early FIrestar with 377 I normally cruised at > around 5200 rpm. No signs of trouble at all with that engine at near > > 500 hours on it when I sold the airplane. > > Thom in Buffalo > do not archive > > > > > > > ________________________________ Message 8 _____________________________________ Time: 11:22:21 AM PST US From: ElleryWeld@AOL.COM Subject: Re: Kolb-List:engine replacement time No I got busy working on everyone elses Planes and never got the time to install my floats but if the weather gets bad this winter mabe I can find time to do it then I will post it when ever it happens Ellery with 2 sets of floats that haven't seen water do not archive ________________________________ Message 9 _____________________________________ Time: 12:56:37 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Overhaulin' | stated 1000 hour overhaul? Herb Herb: Isn't operational rpm a design factor? Running an engine too slow can be as harmful to it as over speeding. john h mkIII ________________________________ Message 10 ____________________________________ Time: 01:52:20 PM PST US From: "Richard & Martha Neilsen" Subject: Kolb-List: Kolb Trailer Update I just did my first test fitting of my clam shell doors on my Kolb trailer. The trailer weighs about 1000 Lbs. empty and will hopefully be able to be pulled by my Toyota Sienna. The clam shell doors are made of foam board then fiber glassed. The frame was a boat trailer that I added a tube framework to and covered with pole barn steel. I wanted to have it ready to pull it to Florida this year but it just isn't going to happen. Rick Neilsen Redrive VW powered MKIIIc ________________________________ Message 11 ____________________________________ Time: 02:07:40 PM PST US From: "Jack B. Hart" Subject: Re: Kolb-List: Overhaulin' At 12:44 PM 12/14/06 -0500, Thom Riddle wrote: > >.....Can someone explain to me why it is Rotax can't make 2-stroke >bearings > and/or crankshaft components that last longer than 300 hours > (notwithstanding those that go well over that time limit)? I >mean, is > it a matter of cost/materials, or is it a "no material known to >man > can withstand the stresses involved" kind of thing?..... > Kolbers, It has to do with the fact that roller and ball bearings are used in a low oil environment. Ball and roller bearings do not have a large surface area supported by an oil cushion as do slipper bearings. The ball has almost point contact and the roller line contact so that as the load comes on and off of them they are stressed through the center of the ball and roller. Actual surface deformation takes place as the load comes on and off the bearing. If the loads are low enough so that the deformation does not go beyond the elastic limit, the bearing should hold up forever. But due to material and surface imperfections, a bit of the ball, roller or bearing race surface spalls and leaves a little pit. Then over time additional material will fail next to the original pit etc until the bearing fails. Higher loads accelerate this process. >From Timken: * Doubling load reduces life to one tenth. Reducing load by one half increases life by ten, * Doubling speed reduces life by one half. Reducing speed by one half doubles life. Check out: http://www.timken.com/products/bearings/fundamen/calculate.asp The above assumes constant load at constant rpm. But for an internal combustion engine, the dynamic bearing load varies with crank position and rises dramatically as rpm increases in a crank, connecting rod and piston system. This why the engine explodes if it is over rev'ed. I assume what engine manufacturers gamble on is that the bearings will hold up to the selected TBO. In most cases they do and will go much further depending upon how the engine has been treated and if the engine initially received a very good set of bearings. So they pick a TBO time that they believe is attainable for a high percentage of their engines. If there are no failures in the field they may raise the TBO. No one wants the reputation for engines that self destruct. It is better to have a re buildable carcass. Once you purchase your engine, you can make the choice of how you are going to run your engine. I am not saying to never run your engine up to the operating limit. But I am saying yes run it up there for take off, but bring it on back a bit for cruise. It will be much easier on the bearings, and the chances of making to TBO are increased. Jack B. Hart FF004 Winchester, IN ________________________________ Message 12 ____________________________________ Time: 03:38:34 PM PST US From: N27SB@AOL.COM Subject: Re: Kolb-List: Kolb Trailer Update Rick, Looks good. It looks like yu took Homer's and my advice about using simple curves extended off of the top and sides of your trailer. How much do they weigh? steve ________________________________ Message 13 ____________________________________ Time: 03:58:45 PM PST US From: "Larry Bourne" Subject: Re: Kolb-List: Kolb Trailer Update Perty slick, Rick. You put some serious thought and effort into that. Lar. Do not Archive. Larry Bourne Santa Fe, NM www.gogittum.com ----- Original Message ----- From: Richard & Martha Neilsen To: kolb-list@matronics.com Sent: Thursday, December 14, 2006 1:51 PM Subject: Kolb-List: Kolb Trailer Update I just did my first test fitting of my clam shell doors on my Kolb trailer. The trailer weighs about 1000 Lbs. empty and will hopefully be able to be pulled by my Toyota Sienna. The clam shell doors are made of foam board then fiber glassed. The frame was a boat trailer that I added a tube framework to and covered with pole barn steel. I wanted to have it ready to pull it to Florida this year but it just isn't going to happen. Rick Neilsen Redrive VW powered MKIIIc ________________________________ Message 14 ____________________________________ Time: 05:02:21 PM PST US Subject: Kolb-List: Ricks trailer/cowl update From: "Craig Nelson" Rick I like the doors. It looks kike the trailer tapers to the front of the trailer? Right? I started the engine with the cowing on for the first time. The back of the cowling shook quite violently. Removed the cowl and put a reinforcement bulkhead in the back where the air exits made of dense foam and carbon - A week later re installed it and it worked well. The baffle I made to force the air through the radiator also worked. Just sitting at idle on the ground I held some plastic streamers at the opening of the cowling at the front and I was amazed at the amount of air being pulled through the cowling. But had another set back. The engine has just 8 hours on it most came B4 the hard landing over two years ago. As we were running the engine and got it to operating temp oil was leaking all over the place. We shut it down and started inspecting. I assumed it was one of my oil lines, checked all of them and decided it was one of the fittings not quite tight enough, spraying oil everywhere. Even redid one line. Re started the engine and still oil all over the place. On closer inspection the oil was coming from behind the stator behind the black plastic cover in the front of the engine. I removed the cowling, oil lines, and water lines and all the electrical, then removed the engine and took it to the rotax dealer here in phoenix. The front oil seal was bad. The engine is now ready to go I will get it Monday as I am working in California all week. Hope to have the air worthiness inspection early next year. The engine did not run for the two years Every time I thought about it I would turn the engine over by hand. In a previous post "not running the engine is the worst thing you can do to it" I do believe to be true! glad it let go in the drive way rather than over the Grand Canyon. Uncle craig Do not archive ________________________________ Message 15 ____________________________________ Time: 05:41:59 PM PST US From: "Richard & Martha Neilsen" Subject: Re: Kolb-List: Kolb Trailer Update Steve They weigh 10-15lbs each. The heaviest part is a 3/8" X 5" X 6' plywood part that is glued and glassed to the foam where I attach the hinge. I set one down while I was mounting to other and a 10MPH wind was blowing it around. I only glassed the outside of each door. Each door is a bit fragile when open but should be stronger when both are closed and latched. I will also be adding more foam bracing on the inside. The caned foam "tough stuff" makes a real good foam glue. I was right on track to get the trailer ready for Florida but the weather turned cold around here and the resin took for ever to cure. Thanks for you help. Rick Neilsen Redrive VW powered MKIIIc ----- Original Message ----- From: N27SB@aol.com To: kolb-list@matronics.com Sent: Thursday, December 14, 2006 6:37 PM Subject: Re: Kolb-List: Kolb Trailer Update Rick, Looks good. It looks like yu took Homer's and my advice about using simple curves extended off of the top and sides of your trailer. How much do they weigh? steve ________________________________ Message 16 ____________________________________ Time: 05:58:46 PM PST US From: Dana Hague Subject: Re: Kolb-List: Kolb Trailer Update At 04:51 PM 12/14/2006, Richard & Martha Neilsen wrote: >I just did my first test fitting of my clam shell doors on my Kolb trailer... That's pretty cool, Rick. Does the plane extend into the clamshell portion or is it just empty space? It would be interesting to compare gas mileage with and without the doors. Hoping to pick up my Ultrastar this weekend (with a trailer that needs work). Good to get trailer ideas... -Dana -- -- What has four legs and an arm? A happy pit bull. ________________________________ Message 17 ____________________________________ Time: 08:23:22 PM PST US From: "Larry Cottrell" Subject: Re: Kolb-List: Kolb Trailer Update From: "Larry Cottrell" Subject: Re: Kolb-List: Kolb Trailer Update From: "Larry Cottrell" Subject: Re: Kolb-List: Kolb Trailer Update That's pretty cool, Rick. Does the plane extend into the clamshell portion or is it just empty space? It would be interesting to compare gas mileage with and without the doors. Just wondering what would be the effect of slated pieces mounted just at the end of the trailer that directed the wind back in towards the center of the trailer? Would the force of the wind cause the turbulence to move back far enough that it would not cause drag on the trailer? Or perhaps a wing mounted on the top of the trailer? Larry, Oregon do not archive ________________________________ Message 18 ____________________________________ Time: 08:41:26 PM PST US From: "Richard Girard" Subject: Re: Kolb-List: Kolb Trailer Update Rick, if you decide to glass the inside of the doors, or do another large part, try using electric blankets to help cure the epoxy. Rick On 12/14/06, Larry Cottrell < lcottrell@fmtcblue.com> wrote: > > > That's pretty cool, Rick. Does the plane extend into the clamshell > portion or is it just empty space? > > It would be interesting to compare gas mileage with and without the doors .. > > > Just wondering what would be the effect of slated pieces mounted just at > the end of the trailer that directed the wind back in towards the center of > the trailer? Would the force of the wind cause the turbulence to move bac k > far enough that it would not cause drag on the trailer? Or perhaps a wing > mounted on the top of the trailer? > Larry, Oregon > > do not archive > > * > =========== > > www.aeroelectric.com =========== > > http://www.matronics.com/Navigator?Kolb-List =========== > > * > > ------_NextPart_000_00EE_01C71FC5.EC09EBC0X-Priority: 3X-MSMail-Priority: > Produced By Microsoft MimeOLE V6.00.2900.2869This is a multi-part message > in MIME alternative; > boundary----_NextPart_000_00EE_01C71FC5.EC09EBC0X-Priority: > 6.00.2900.2869X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869Thi sis a multi-part message in MIME > format.------_NextPart_000_00EE_01C71FC5.EC09EBC0Content-Type: text/plain ; > charsetiso-8859-1Content-Transfer-Encoding: quoted-printable That's prett y > cool, Rick. Does the plane extend into the clamshell portion or is it jus t > empty space? It would be interesting to compare gas mileage with and with out > the doors. Just wondering what would be the effect of slated pieces mount ed > just at the end of the trailer that directed the wind back in towards the > =CEnter of the trailer? Would the force of the wind cause the turbulence to > move back far enough that it would not cause drag on the trailer? Or perh aps > a wing mounted on the top of the trailer? Larry, Oregon do not > archive------_NextPart_000_ ----_NextPart_000_00EE_01C71FC5.EC09EBC0-- -- Rick Girard "Ya'll drop on in" takes on a whole new meaning when you live at the airport. ________________________________ Message 19 ____________________________________ Time: 08:47:59 PM PST US From: "Richard Girard" Subject: Re: Kolb-List: Any suggestion for a good cleaning of a 912ul? See if any of the industrial tool suppliers can get you a tube of "Knorrostol". Works great on aluminum or steel. Rick On 12/14/06, John Bickham wrote: > > > Hello List, > > Getting closer. Finally finished painting Tuesday. > > Ready to put engine on airframe. Need to give it a good cleaning. Easy to > do now while on bench. > > Appendix D > (a) Each person performing an annual or 100-hour inspection shall, before > that > inspection, remove or open all necessary inspection plates, access doors, > fairing, > and cowling. He shall thoroughly clean the aircraft and aircraft engine. > > Any suggestions on what to use (or not to use)? Some of the aluminum is a > little weathered and has a slight white crust (alum corrosion). > > -------- > Thanks too much, > > John Bickham > Mark III-C > "Using my Repairman Certificate" > St. Francisville, LA > > Do Not Archive > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=81509#81509 > > -- Rick Girard "Ya'll drop on in" takes on a whole new meaning when you live at the airport. ________________________________ Message 20 ____________________________________ Time: 08:51:54 PM PST US From: "Richard Pike" Subject: Re: Kolb-List: Overhaulin' If you are lugging the engine, yes. If the engine is not being lugged, no. Jack Hart in his post on this subject gave an excellent analysis on the situation, as the crank load goes up expotentially as the rpm's increase, & the crank life is greatly extended by cruising at lower rpm's. That is why I am still in pursuit of streamlining & cleaning up the MKIII so that it becomes possible to attain acceptable cruise speeds at minimal 582 cruise rpm's. Right now I am able to cruise at 65-70 mph at around 5300 rpm's, and the bird is currently in the garage awaiting more streamlining so that it will (hopefully) become even more efficient. Don't know if I will accomplish anything or not, but the goal is to cruise at 65-70 at 5200 rpm or less. Not to mention that at this rpm the fuel burn is just slightly above 3 gph. And it is comparitively very quiet. Richard Pike MKIII N420P (420ldPoops) ----- Original Message ----- From: "John Hauck" Sent: Thursday, December 14, 2006 3:55 PM Subject: Re: Kolb-List: Overhaulin' > Isn't operational rpm a design factor? > > Running an engine too slow can be as harmful to it as over speeding. > > john h > mkIII > > > ________________________________ Message 21 ____________________________________ Time: 10:08:46 PM PST US Subject: Kolb-List: Hirth and Rotax a comparison From: Herb Gayheart John I agree and would ask..are Rotax engines designed to run at 75% power to achieve TBO? For instance, that would be abt 5100 RPMs for a DCDI 503. Abt 39 hp.. The roughly equivalent Hirth is the 3702 which develops 55 hp at 5500 rpms.. Its 75 % power is at 4100 rpms.. 41 hp. Herb On Thu, 14 Dec 2006 14:55:53 -0600 "John Hauck" writes: > > | The lower rpms of the Hirth engines might account for some of > their > > Herb: > > Isn't operational rpm a design factor? > > Running an engine too slow can be as harmful to it as over > speeding. > > john h > mkIII > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-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/kolb-list Browse Digests http://www.matronics.com/digest/kolb-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.