I have told this basic story before a few years ago, but here goes anyway, pay attention it concerns one KR2. A friend of mine was doing touch and goes in his newly acquired KR2. On one of the touch and goes as he was climbing out, the engine quit, we all later assumed vapor lock because there was no fuel pump, just gravity feed plus the gascolator was exposed in the engine compartment with no shielding or insulation. We thought that since he was just going around the pattern doing touch and goes that heat built up in the tightly cowled engine compartment and caused the vaporlock. The engine was a Revmaster and was a great looking engine. He thought the plane was going to stall because he was climbing out and it decelerated quickly when the engine quit, but he managed to get the nose down pointed straight at the ground trying to get some flying speed, he said he thought he was a dead man, not sure exactly how or what happened but the engine restarted right before he hit the ground and he managed to get the nose up just enough to pancake into the runway. It sheared both sides of the propeller off in the thick part near the hub, not on the outer parts like Marks. I may still have that part of the prop still around here if someone is interested in a photo of it. The plane was brought to my hangar home for repairs. I called Joe at Revmaster, told him what happened and asked his advice as to what he thought. He said that the engine was probably OK after I told him that I had checked the runout on it and found it to be perfect. He did tell me that his job was to tell me to take the crank out and have it checked but that if it was his own, he wouldn't be worried about it. Later the plane was sold and the story was passed on to the new buyer. He elected to remove the engine, tear it down and sent the crank to Revmaster for them to check. It came back perfect, no cracks, no nothing it was OK. The serial numbers on this particular Revmaster engine showed it to be one of the engines that was sold to Quickie Aircraft Company that had been sent out with a Quickie Q2 kit. A lot of the Revmaster engines that have been for sale from time to time are Quickie kit engines. They were about 60 or 65 hp engines I believe. A lot of guys either decided to use an O200 when Quickie changed over to selling Q200s, sell their kits or whatever but there were quite a few of these engines floating around there at one time.These engines must have one heck of a crank in them is all I can say. The statements in the posts below about damaged VW cranks is certainly something to think about, especially if you have a normal VW crank in your engine. I do not consider a Revmaster crank a normal VW crank. I do not know if Revmaster nitrides their cranks but I am a believer in how tough and strong their cranks are. Something to keep in mind on a regular aircraft engine is there is a big difference between a wooden propeller hitting the ground and a metal prop hitting the ground. There is a big difference between a prop hitting the ground and the engine still running as compared to a prop hitting the ground and causing a sudden engine stoppage.
My second point is for everyone that has or is thinking about the inboard stub wing fuel tanks. This plane was a tail dragger, it had the in front of spar Diehl landing gear brackets and fiberglass landing gear like most of you have. When this plane hit the ground one of the fiberglass landing gears broke in half and the wheel and half the landing gear went backwards and came through the wing walk area where the inboard wing tanks are. The other landing gear broke outwards and went through the bottom of the wing where an outer wing tank would be on some KRs. The point here is that this plane only had a header tank. In this mishap, no fuel spilled anywhere, the header tank was fine, no damage, if it had stub wing tanks the scenario may have been very different, gasoline definitely would have spilled out and it may have started on fire or blown up. I am writing this just so you with stub wing tanks can be aware of this. Fly Safe Larry H. > I heard a rumor that one of the previous owners of a KR I bought had a prop > strike. The prop looked like it was new, but the guy denied the prop > strike. I checked the hub for runout and it was fine. I pulled the crank > anyway and had it magnafluxed and the shop told me that they found the > biggest crack through the keyway that they had ever seen. Glad they found > it and not me. > > Brian Kraut > Engineering Alternatives, Inc. > Subject: KR> prop strike > > > I had a nose over that broke the > prop. I called Revmaster about the need for a rebuild. Joe said try > to start it first. > > Sorry gang, but I am on a soap box this morning. Larry I normally agree > with most of what you say, but read what you said again.. > To me that is totally irresponsible to post to a bunch of builder would be > pilots who might not know any better. Standard procedure in certified > engines is a complete teardown after ANY prop strike. All the testing on > the ground you want to make will not show you the cracks, nor will it prove > it is not cracked. I knwo of three netters on this list alone that have had > crankshafts crack after they were told no, but later found out in fact their > planes sufferred a prop strike. Do what you want to but PLEASE don't tell > people that it is acceptable or correct to fly an engine after a prop > strike, without having the crank removed and magnafluxed. The only possible > exception would be to ferry it to a location to get it torn down... > > > Colin Rainey > First National Mortgage Sources > Lending Solutions in All 50 States > 386-673-6814 office > 407-739-0834 cell
