---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Fri 01/24/03: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:40 AM - Trim system (Richard Neitzel) 2. 12:13 PM - Airplanes (John Hauck) 3. 12:32 PM - Re: Trim system (Richard Pike) 4. 01:02 PM - Re: Trim system (NealMcCann@aol.com) 5. 01:38 PM - Re: Trim system () 6. 07:31 PM - Preservation of two cycle engines (SGreenpg@aol.com) 7. 10:44 PM - Re: Preservation of two cycle engines (Don Gherardini) ________________________________ Message 1 _____________________________________ Time: 08:40:24 AM PST US From: "Richard Neitzel" Subject: Kolb-List: Trim system --> Kolb-List message posted by: "Richard Neitzel" Top of the morning from sub zero Wisconsin! I have a concern about the trim system on my Mark III Classic. I fished through the parts bin and located the springs that connect the trim lever to the elevator bellcrank. They appear to be extremely strong springs for this application. I can just barely pull one spring back by hand, much less two. I double checked the springs against the plans and what I selected appears to be the correct spring. It appears that the purpose of this spring system is to hold the elevator in a neutral position at rest and apply back pressure to trim in flight. With the springs supplied it would seem difficult to overcome this spring tension. Has anyone else substituted lighter springs? I found a spring that is quite a bit longer that not only eliminates the harness assembly but balances the elevator and can easily be over powered with the application of down elevator. Do these springs really have to be that heavy? I also am wondering what kind of tension is applied to the elevator cables. If mine are adjusted loose so the elevator moves freely the cables slap on the boom tube. When I go tight enough to eliminate the slapping then there is a quite a bit of stiffness in the system. With no cables attached everything moves freely with no binding. Maybe a little slap is ok?? Another problem that I ran into was with the chokes (enricheners) on the 582. With the stock springs above the enrichening valves I could not pull them on from the cockpit. I substituted some weaker springs and WD-40ed the cables and now I can operate the lever freely. Anybody else run into this problem? If so what was your cure? Also someone was concerned about powder coating on bolt shanks and in other areas that it really shouldn't be. I discovered by accident that Acetone dissolves power coating. It doesn't peel it up like a paint remover but after a brief soaking it is softened enough so that gentle scraping will remove the unwanted coating. Worked great on the bolts of the bellcrank and throttle. I took a short length of plastic tubing and pinched one end closed with a pliers, added a small quantity of Acetone then submerged the bolt. That way I could control where solvent went. Thank you all ahead of time. Sure enjoy the flow of information on this site. Wood furnace is finally starting to take the bite out of the air so better get busy. Richard Neitzel Mark III Classic neitzel@newnorth.net ________________________________ Message 2 _____________________________________ Time: 12:13:09 PM PST US From: John Hauck Subject: Kolb-List: Airplanes --> Kolb-List message posted by: John Hauck Hi Gang: Got my new Experimenter Mag this morning. Lo and behold, there was John Williamson and his Kolb Kolbra right there in the middle of the magazine. http://home.sw.rr.com/jhauck/Flying%20Friends/J%20Williamson1.JPG http://home.sw.rr.com/jhauck/Flying%20Friends/J%20Williamson2.JPG Not to be outdone, Big Lar sent me a picture also, standing in front of a little Piper J5 Cruiser. http://home.sw.rr.com/jhauck/Flying%20Friends/Larry%20and%20J-5.JPG john h DO NOT ARCHIVE ________________________________ Message 3 _____________________________________ Time: 12:32:56 PM PST US From: Richard Pike Subject: Re: Kolb-List: Trim system --> Kolb-List message posted by: Richard Pike At 10:44 AM 1/24/03 -0600, you wrote: >--> Kolb-List message posted by: "Richard Neitzel" > >Top of the morning from sub zero Wisconsin! > >I have a concern about the trim system on my Mark III Classic. I fished >through the parts bin and located the springs that connect the trim lever >to the elevator bellcrank. They appear to be extremely strong springs for >this application. I can just barely pull one spring back by hand, much >less two. I double checked the springs against the plans and what I >selected appears to be the correct spring. It appears that the purpose of >this spring system is to hold the elevator in a neutral position at rest >and apply back pressure to trim in flight. With the springs supplied it >would seem difficult to overcome this spring tension. Has anyone else >substituted lighter springs? I found a spring that is quite a bit longer >that not only eliminates the harness assembly but balances the elevator >and can easily be over powered with the application of down elevator. Do >these springs really have to be that heavy? Yep. You'd be amazed how much back pressure it takes when you have a big passenger. Remember that all the useful load of people is ahead of the CG. >I also am wondering what kind of tension is applied to the elevator >cables. If mine are adjusted loose so the elevator moves freely the >cables slap on the boom tube. When I go tight enough to eliminate the >slapping then there is a quite a bit of stiffness in the system. With no >cables attached everything moves freely with no binding. Maybe a little >slap is ok?? Clang, bang - it's a MKIII all right... >Another problem that I ran into was with the chokes (enricheners) on the >582. With the stock springs above the enrichening valves I could not pull >them on from the cockpit. I substituted some weaker springs and WD-40ed >the cables and now I can operate the lever freely. Anybody else run into >this problem? If so what was your cure? Didn't notice a problem. If there is any leakage where the enrichners press into their place, you will get extra fuel. >Also someone was concerned about powder coating on bolt shanks and in >other areas that it really shouldn't be. I discovered by accident that >Acetone dissolves power coating. It doesn't peel it up like a paint >remover but after a brief soaking it is softened enough so that gentle >scraping will remove the unwanted coating. Worked great on the bolts of >the bellcrank and throttle. I took a short length of plastic tubing and >pinched one end closed with a pliers, added a small quantity of Acetone >then submerged the bolt. That way I could control where solvent went. > >Thank you all ahead of time. Sure enjoy the flow of information on this site. > >Wood furnace is finally starting to take the bite out of the air so better >get busy. > >Richard Neitzel Mark III Classic neitzel@newnorth.net > > Help Stop Spam! Delete all address information (especially mine) off everything you forward, and make Blind Carbon Copy a way of life. Thanks! And have a blessed day. rp ________________________________ Message 4 _____________________________________ Time: 01:02:05 PM PST US From: NealMcCann@aol.com Subject: Re: Kolb-List: Trim system --> Kolb-List message posted by: NealMcCann@aol.com Hi guys, On the issue of choke cables, etc....during some safety issue talks in our UL flying club, some members advised us to use graphite or other means of lubrication other than using WD 40. I think WD 40 is more of a water based substance which could introduce freezing cables up in cold weather operation and possibly rust in the future. I never used WD 40 but I flew on a cold Sept. morning a few days after my FS II was out in the rain, and I had the throttle stick wide open. I had to dead stick land since I had to kill the ignition. I believe the moisture seeped into my cables (dual card 503) from the previous rainfall and froze up during the flight. Anything like this happen to anyone else. Neal McCann FSII 503 ________________________________ Message 5 _____________________________________ Time: 01:38:03 PM PST US From: Subject: Re: Kolb-List: Trim system --> Kolb-List message posted by: Richard, I had the same problem with my enrichers on my 690, except I have three carbs instead of two, I think a lot of the stiffness is due to the 180 degree turn in the cables between the carbs and the splitters. I also installed lighter springs, but as Richard said, we will both have to watch our EGTs for signs of leakage. The springs I used seem to be plenty heavy, but time will tell the story. On the trim problem, I have not flown mine yet but I also have double springs, mine are 5.5 inches long between centers of bolt hole loops, .5 inches in coil diameter, and the wire cross section is a good 1/16 of an inch thick. These are 1992 vintage Kolb springs. I do not seem to have the drag in my elevator linkage that you have, my turnbuckles are cranked pretty snug. I do not have the left side tail wires on right now (stabilizer and elevator are setting on a stool) so I can't shake it to check for slapping, I imagine it will with that small of clearance over the length of the boom. Wow building a Mark-3 classic in sub zero temps and wood heat, you would be right at home at the Rowe house. :-) Good luck, Denny Rowe Mk-3 N616DR Leechburg, PA ----- Original Message ----- From: Richard Neitzel Subject: Kolb-List: Trim system > --> Kolb-List message posted by: "Richard Neitzel" > Richard Neitzel Mark III Classic neitzel@newnorth.net > > ________________________________ Message 6 _____________________________________ Time: 07:31:31 PM PST US From: SGreenpg@aol.com Subject: Kolb-List: Preservation of two cycle engines --> Kolb-List message posted by: SGreenpg@aol.com Kolbers, While looking for the root cause of the rod bearing failure on my, 210 hour since new, Rotax 582 I would always get asked the same questions by the service shops that I talked to. Did the engine set for long periods of time without running it? Did you follow the preservation procedures? Probably the longest the engine set without running was about a month. I accumulated 210 hours in 18 months. And no I didn't follow the preservation procedures. The procedures in the operators manual say to inject approx. 3 cc of oil into each carb. and then run at high idle for 10-15 seconds with the engine warm. This is if not running for 1-4 weeks. My solution, on the new engine, was to install a primer pump and connect the discharge to the carbs where you would normally connect the primer and "teed" into the oil line from the oil injection tank for the supply. The primer pump displaces 2.5 cc per stroke so 2 full strokes and part of another just before shutting down and that part of the preservation is done without removing the air filters. Steven Green Mk III 211 hours N58SG ________________________________ Message 7 _____________________________________ Time: 10:44:43 PM PST US From: "Don Gherardini" Subject: Re: Kolb-List: Preservation of two cycle engines --> Kolb-List message posted by: "Don Gherardini" hmmm....Well Steve, that suprises me...I mean when you said what all the rotax service shops asked you. If a fella has an engine and a rod bearing fails on a Honda GP engine, and calls us, ( I work for Honda GP and industrial engine division).....The first question we would ask is whas the possibility of an intermittant load on the output side of the crank? Was it hookd up to a gearbox?..If so how much lash was in the gears and if we found out it was on a ventalation fan of some kind, (closest thing to an airplane Honda would approve) Then are the blades turning in free air, with no obstacles to cause a pressure pulse to be transmitted thru the crank. This particularly if the bearing looked "hammered" apart...and not just simply overheated. This happens alot, and if it came into question about warranty, then we would send some engineer out (probably me if its in the midwest) and qheck the installation. If I saw the same kind of config as we have on a Pusher aircraft installation, then I would quickly examine the gearbox if there was one used...(Like we use on an airplane) and If it was not tight as hell, with almost no lash, I would blame the rocking motion on the load as the pressure pulses in the air caused by the intake airflow disturbance as some air flows around the obstacles and some air is "clean"....,, for the failure. I would say.."I'm sorry sir, but warranty will not apply in this case". Then if he asked me for some advice on how to keep it from happening again, ( this is assuming he would speak to me at all after the warranty denial)...I would suggest a number of things that Might help. 1st....get a new gearbox,or overhaul the one you have and get it as tight as possible before heat develops, and if there are none that are any better than just about every gear reduction unit that I have EVER seen on a Rotax, or a Hirth or a 2Si, or any like we must use in the Small plane biz, ...... then try a different drive...I always suggest a gates poly chain setup..( I should get commission for gates as much as that comes up) for it is the best economical "high Shock" power transfer I know of . Unless you can get away with a v-belt. 2nd...try and clean up the "obstacles" and get as much of the airflow entering the blades to do so at the same speed and the same direction. 3rd..run as long an extension on the shaft as you can to get the blades as far away from the pressure differential as you can. This scenario has been run many times in my biz. I may be wrong, but as I look at our aircraft installations, I wonder if this is why we see so much crankshaft and bearing failures, this coupled with running our engines at over 100% duty cycle so much of the time by governing the rpms with the load while maintaning wide open throttle is awful tuff on em! Don Gherardini FireFly 098