Hi Net Page 2. The past couple of days have been busy opening two engines. First of all I had a type 2 in the shed that I want to use for the case. The reason for this is that the type 2 case has the fuel pump. A down stream plan of mine may require the use of an engine driven pump. Now back to the engine from N110LR. I removed the cylinders and pistons while the engine was mounted to the aircraft. From that distance the cam and crank looked real good. As the engine got lighter and I could lift it, I removed it from the aircraft. After finding the correct metric 12 point star bit to remove the flywheel bolts, I proceeded to split the case and extract the crank and cam, for better inspection. On close inspection I could see ware patterns in the cam. The wear was slight and if I was not going to go for a different lift, I would have reused the cam and lifters, which show no visible signs of wear at all. The crank looks real good also. My current plan is to replace my 66mm crank, 96mm pistons and current cam with a 71mm crank, 103mm pistons, Force One bearing and a 490/275 cam. At this point I must express concern for any one flying an engine that they did not assemble, unless they are certain it was put together by a reputable person. After I removed the flywheel, I found that the case bolt that was supposed to be hidden behind the thing was in fact never installed. That somewhat explains the oil on the bottom of the case. Another strange thing about the assembly of this engine was that the nuts for the primary case bolts, the one's with the seals, were installed upside down. The neat thing about opening two engines at the same time is the side by side comparison that you can do. The type 2 case had an oil splash or windage tray in the bottom of the case. My type 4 did not. The other odd thing about my engine (type4) is that the front bearing (Number 4 main bearing, pulley end) was omitted completely. In place of the front bearing the prop hub lay in it's place. The hub is approximately the same diameter is the bearing shell. One must remember that this engine was assembled around the same time as the advent of the Force one bearing. For me the question comes to mind, what kind of wear is transmitted from the rotating bearing to the case. Did the builder intend for loads to be transmitted directly to the case?? It almost looks like it, except that there is not much indication of rotation on the prop hub. If I had the time I would use some plastic gauge to measure the space. If that is true, then the prop was completely unsupported through to the first journal. (any one with knowledge can jump in here) All and all this has been a day of discovery.
Orma L. Robbins Southfield MI 19 Years flying KR-2 N110LR http://www.aviation-mechanics.com
