| Author | Message | ||
     Larry Hoppe |
I understand that the 2000 series main gear are being tilted forward to relieve some of the load on the nosewheel when using a six cylinder engine. What is the degree of tilt - 4 deg.? Does anyone have the measurements of the distance between the existing holes in the outer gear bracket and the holes in which the gear attachment is placed? I have the old brackets and would like to modify them versus starting over with new brackets. | ||
| Bill C |
Larry: You may be trying to do something that is not really worth the effort. This "fix" has been discussed over and over through the past 8-10 years and few have attempted it. By 6 cylinder engine I assume you have in mind an IO-540 Lyc or larger. If that is true then look around at the many, many examples flying with the original design with out any problems. Ours is one example. We are using an IO-540 Lyc and have balanced it by placing the batteries for our dual electrical system behind Blkhd 162. We are using EDI produced steel gear legs. At our empty weight our nose gear carries 394 lbs. which is generally considered light for the type. If you can project the weight on your nose gear to be less than 400 lbs., and your nose gear strut is properly constructed, you should have no problem. One other thing about placing the main gear legs, install them as far toward the upper skin as possible w/o enlarging the hole in the rib. We ended up with a 1/2 inch spacer between the leg and bracket to keep the tail from "dragging". The nose gear strut can be adjusted to accommodate the added height. | ||
| Bob Gisburne (Gisburne) |
Larry: I concur with Bill C. I had 310+ hours on my S-90 conversion with steel legs prior to the failure of the inboard gear attach weldment. My W&B showed 425 lbs. on the nose with never any adverse effect. For some other reasons, mainly heat releated, I moved the battery from on the firewall to aft of the 162 bulkhead with a new weight on the nose of 365 lbs. I now have the 'glass legs... see the thread above... they are fine, but the rib R brackets do not bolt in as I thought they would. I understand that Larry can/may fab a new bracket for you using the exiting bolt pattern. Check with Larry... I also found the steel gear much easier to work with in terms of setting camber and toe. In summary I would have no qualms about using the steel gear, except be sure to inspect/install the beefed up inboard gear attach fittings! Happy New Year! Bob Gisburne N4382A | ||
| rob jordan |
With the battery(s) being put behind blk 162 what size battery cables are you guys using and does it turn the engine over well ? | ||
| Bill Copeland |
Rob: We are using No. 0 size cable for our main battery leads and recommend that you consider using standard No.0 size, rubber insulated welding cable. Much cheaper and much more flexible. We use No. 8 leads for the aux batt system. We recommend AGAINST using aluminum - but you knew that!! So far we have not experienced any problems starting the engine - in fact our airplane sat at the factory for nearly two months while additional instrumentation was being installed and it fired right up last Friday. Bill C. | ||
| Bob Gisburne (Gisburne) |
Rob: I have about 200+ hours with the battery aft. Never a starting problem. One dead battery due to operator error, (I left the cabin light on...) I attribute some of my good fortune to the electronic ignition I use in place of one of the mags. I used No. 0 cable as well. My battery is a lightweight version from B&C... next time I have the bulkhead cover off, I'll record the size. Bob G. N4382A | ||
| Reinhard Metz |
Some comments on several items in this column: Fuel flow sensor position: I have mine on top of the engine, and it has been working fine for 300+ hours. I have seen many, if not most of the factory-built (Beech, Cesna, etc.) applications using the same flow sensor on certified fuel computers mounted in the same place. As far as heat is concerned, it is at near-outside air temp there in flight, much better than stewing in the area between baffles and firewall. Which brings me to the next topic: Engine driven fuel pump pressure drop (at altitude): I have seen this several times on my I/O-360 installation, with a brand-new pump, and after discussions with several people have come to the following conclusions: The pumps are all somewhat anemic, but the root cause is vapor lock cavitation in the fuel line between the electric boost pump and the engine driven pump, which occurs due to heat in the area and the fact the pump "sucks" on the fuel at this point, rather than "pushing". I have significantly improved the situation with insulation on the line, but in very hot weather, pressure drops sometimes still occur, and after landing and a long taxi, the boost pump may be required to keep the engine from quiting. Left wing heavy / trim tab: Mine also is left wing heavy when I am alone, but is fine when with a right seat passenger. I would not recommend a trim tab. When alone, I burn some of the left tank first, and let the autopilot take care of the rest. Metal gear and gear position: Boy, this topic has staying power! I have over 300 hours on my steel gear and it is fine. I have the upgraded inner brackets, which get a close inspection every few months, and look perfect so far. I did make one modification: The inboard brackets have a slot, a bushing in the slot, and a bolt through the center. This arangement starts out with a little bit of clearance, which hammers the bracket and bushing at each landing, causing it to hog out the slot and smash the relatively soft bushing (which transfers all it's force on a line), and creating an impulse which probably has contributed to failures where they have occurred on other folk's planes. I machined out the bracket slot slightly to make it smooth again, and made a new bushing, machined out of grade 8 bolt stock, and with flats on the top and bottom. Now there is no clearance, and the force transfer is through a flat surface, rather than on a line (defined by the round bushing against the slot). Landings now produce absolutely no gear-related noise, a much more confidence inspiring situation. The gear also doesn't clatter up and down in heavy turbulence anymore either. Concerning the gear forward angle and reducing nose gear weight, I have some forward angle, as the brackets allowed, but nothing extraordinary. Some time ago I generated a spread sheet analysis that shows the gear position impact is not nearly as significant as folks thought. The average sensitivity of the nose gear weight with respect to main gear position is about 18 pounds per inch. That is if you tilt your main gear forward two inches at the wheel (what you get with 4 degrees), all you get is a reduction of 36 pounds. Mine is fine, if not a bit light on landing with rear seat passengers, at 365 pounds on the nose gear. Needle bearing upgrades: I've looked into this some, especially since the factory now uses them, and have mixed feelings. I think the main benefit may be a small amount of play reduction. But after investigating the fiber originals, they are not half bad. The intuitive reaction is that they appear inferior to metal, will wear, bind, etc. But the actual data (check it out in the McMaster Carr catalog!) is that they are incredibly load-capable - but restricted to low RPM applications, which this is. And they are easy to install with perfect alignment by mill fibering with the applicable tubes in place. More care is required to get the needle bearing flange mounts aligned properly. Reinhard Metz, N49EX | ||
| Rob Jordan |
Thanks for the helpful info guys. This is a great forum. one of the best I've seen Thanks for providing us such a wonderful site for exchanging Info and Ideas. | ||
| Brian McKinney (Bmckinney) |
Does anyone recognize the nose gear shown below? It came with my kit (Wheeler/Auriga), but I don't know if it is the Wheeler, EDI, or Auriga version.  | ||
| Bill Copeland |
Brian: I believe what you have is an Auriga example. I will check out some photos I have of an Auriga currently located in Virginia. Will let you know. Bill C |