Anyone who has one installed, has bought, or is considering buying a new manufacture crankshaft from Continental needs to know there is a VERY SERIOUS SAFETY ISSUE with the new cranks.
These new cranks, p/n 653382 are also used in the IO-360 Continental which has a constant speed prop requiring a pressurized supply of oil for prop operation.
The crank is hollow from the prop flange to the crank throw on #6 cylinder. There are oil supply holes drilled thru the crank wall adjacent to the front main bearing to supply oil to the constant speed prop. There is a press-fit bushing inserted into the prop end of the crank and located adjacent to the oil supply holes in the crank. The bushing has oil holes drilled to supply oil to the prop on the front side and a solid back side to seal off the hollow shaft. The IO-520 crank has the same part in it.
Crankshaft bushing front side
Crankshaft bushing back side
There is a straight thread plug fitted with a crush washer screwed into the straight thread hole in the bushing from the front side thru the prop hub. This plug was not safety wired, Locktite'd, tab washered, or secured in any manner other than specified torque. These type plugs are used in other places on Continental engines. In ALL other cases they are safety wired.
I bought a factory-in-the-box-new crankshaft from Continental when the engine was rebuilt in the summer of 2006. In December, 2006 I had 9 hours total time on the new rebuild.
On the last flight everything was normal at pre-flight and take-off. No oil leaks anywhere and no oil on the windshield. Within 10 minutes of take-off oil started accumulating on the windshield so I returned to the airport. By the time I landed with a total flight time of 20 minutes, the windshield was covered with oil coming out of the spinner.
As-found condition after removing spinner
The engine rebuilder was called to inspect the situation and screwed the plug in three turns before it bottomed out and another 1/2 turn before it torqued up. The plug has four threads. It was less than one thread away from falling completely out! Had that happened, the engine oil would have been pumped overboard out of the 3/8" hole at 45psi. It probably would have taken only a few seconds to empty the sump.
I have talked to two tech reps at Continental in the past week hoping to get some guidance from them before writing this post. Neither one has bothered to call back. The first guy offered no suggestions what-so-ever. The second guy said and I quote,"Just put a new crush washer on it and screw it back in. We have a lot of these out there and usually don't have a problem with them". USUALLY???? How many oil starvation accidents does it take to impress these people? This guy couldn't even give me the proper torque to use much less suggest a fix that might actually work for the life of the engine! The first failure occurred 9 hours from NEW!!!
I asked the second guy what were the chances Contintntal could send me a bushing without the oil holes drilled. He said,"Zero, they only come one way and that's what you have." These people are unbelievable. They sell you a new part that is defective and refuse to offer a credible solution.
UPDATE:
1/29/2007- I called TCM for the third time because no one had returned my first two calls. I talked to the first guy again and he apologized for not calling back. He had done nothing in regard to the problem since my first call. I told him what I was looking for was an actual solution for the problem such as a bushing with no oil holes or some means or method to positively lock the plug in place. He consulted with his supervisor and they decided "without a certification process for a new bushing, we recommend putting the plug back in with a new crush washer at the correct torque", just like it was shipped from the factory. I told him I was very disappointed with the answer and was hoping TCM would have come up with an actual fix. I told him ±20 minutes to engine failure was not acceptable and he agreed. The problem needs to be fixed before I am comfortable flying the plane. I need to fly it from Alaska to Texas and there is no way I would risk it with their recommendation. I then told him the engine installer had given me an FAA "Malfunction or Defect Report" and had recommended we submit it since there are many other crankshafts out in the field with the same problem. I had hoped TCM would have come up with a fix so I wouldn't have to send it in. But if TCM sticks by its recommendation to reinstall the plug with a new crush washer, then that is unacceptable and I'll be compelled to submit it. He then said he would take another look at it and get back with me. I gave him two phone numbers and told him I would be waiting.
) that the only difference in the C-145/O-300 engines with controllable props was the valve in the case to control the oil pressure to the front of the crank. I guess the cranks are different too?
