epopper
Well-Known Member
- Joined
- Nov 3, 2015
- Messages
- 703
- Reaction score
- 285
Last November, I discovered a sheared stud on the number 2 cylinder on the engine of my Arrow. My mechanic removed the cylinder and we discovered cracks in the crankcase through another cylinder stud. The engine only had 350 hours since overhaul. The overhaul was done at a maintenance shop and we believe that the cylinder studs were not torqued properly, which lead to the issues. Also, upon disassembly, we discovered pitted lifters and fretting of the crankcase halves. The overhaul was poor at best and has opened my eyes to so called "spray paint" overhauls. BTW, the engine log reflected what appeared to be a thorough overhaul, using appropriate vendors for the case and crankshaft and noting applicable AD's. The problem was likely due to a lack of precision and attention to detail during the reassembly.
I had a custom engine shop in the Chicago area do the overhaul and man it turned out nice. In the end, I either replaced or overhauled everything forward of the firewall including the engine mount, baffles, mags, and all hoses.
As I showed in another thread, I used a company called Lycon to CNC a groove in the crankcase flange and use a rubber gasket for a seal versus silk thread.
I also took the opportunity to strip some awful flat black paint of of the firewall. This took about 12 hours with a toothbrush and acetone and MEK.
The engine mount was original and likely had never been removed from the aircraft. The mount needed 18 of 22 tubes replaced.
Of course, the only thing left untouched was the propeller governor. It leaked oil prior to the overhaul and I thought it was from the case gasket. It still leaks and it appears to be from one of the other seals on the governor. It comes off soon for a reseal...
Eric
Photos:
I had a custom engine shop in the Chicago area do the overhaul and man it turned out nice. In the end, I either replaced or overhauled everything forward of the firewall including the engine mount, baffles, mags, and all hoses.
As I showed in another thread, I used a company called Lycon to CNC a groove in the crankcase flange and use a rubber gasket for a seal versus silk thread.
I also took the opportunity to strip some awful flat black paint of of the firewall. This took about 12 hours with a toothbrush and acetone and MEK.
The engine mount was original and likely had never been removed from the aircraft. The mount needed 18 of 22 tubes replaced.
Of course, the only thing left untouched was the propeller governor. It leaked oil prior to the overhaul and I thought it was from the case gasket. It still leaks and it appears to be from one of the other seals on the governor. It comes off soon for a reseal...
Eric
Photos:
