I've read quite a bit online from Mike Busch and my instructor swears by him. I like his statistical analysis a lot. However, he's never actually worked on airplanes for a living.
When my airplane was losing compression in two cylinders, losing power and using oil, and developing a little bit of a knock, a local 30 year AP/IA engine guy was recommended to me. Now keep in mind we are starting out with one channel chrome cylinder, one standard chrome, one steel, and one oversize steel, two of which had been replaced 300 and 600 hours ago. We pulled a cylinder and found that I had two cylinders (2 and 4) with bad rings. These same cylinders had bad skirt wear, some pitting in the lower end of the bore on one, and the piston pins were frozen, we had to beat them out. He inspected the cam, lifters, and we pulled the rods. Cam and lifters have no corrosion. Rod journals measured right in the center of new limits. Even with 2000+ hours on the engine, the 30 year AP/IA and engine specialist said that the bottom end looks to be in good condition and it would be worth doing O/H cylinders if the goal was simply to get a couple more years and renewed confidence for a couple hundred hours out of the engine. This is a guy who has an engineering degree and has traveled the world maintaining everything from 757s to J-3s to Bell Jet Rangers in Alaska to Cobra gunships in Vietnam and spent the last 30 years doing mainly GA engine rebuilding and maintenance. He seems to do good work. He insisted on checking the rod bearing journals, NDT ing the rods, new bushings, new big end bearings. I personally observed him torquing the through bolts and cylinder nuts to spec in stages, and double checking them. In all his years of fixing airplanes, he has had one airplane that he worked on crash, and the cause was not related to what he worked on.
So I recently find some articles that Mr. Busch has written and he pretty much makes it sound like if you take more than one cylinder off, or (gasp!!!!) take ALL of them off AT THE SAME TIME, you are DOOMED!
My question is this: is it true that airplanes are falling out of the sky left and right because people made bad decisions and replaced all the cylinders at once on their otherwise serviceable airplane engine?????? With bottom ends on flight school airplanes with my same engine (O320) going to 3500-4000 hours on a regular basis, and his inspection of my engine being OK, I think I made the right choice at a total cost of $4000 vs. $14000 for a major overhaul. The guy who did my work hasn't lost an engine yet in 30 years.
When my airplane was losing compression in two cylinders, losing power and using oil, and developing a little bit of a knock, a local 30 year AP/IA engine guy was recommended to me. Now keep in mind we are starting out with one channel chrome cylinder, one standard chrome, one steel, and one oversize steel, two of which had been replaced 300 and 600 hours ago. We pulled a cylinder and found that I had two cylinders (2 and 4) with bad rings. These same cylinders had bad skirt wear, some pitting in the lower end of the bore on one, and the piston pins were frozen, we had to beat them out. He inspected the cam, lifters, and we pulled the rods. Cam and lifters have no corrosion. Rod journals measured right in the center of new limits. Even with 2000+ hours on the engine, the 30 year AP/IA and engine specialist said that the bottom end looks to be in good condition and it would be worth doing O/H cylinders if the goal was simply to get a couple more years and renewed confidence for a couple hundred hours out of the engine. This is a guy who has an engineering degree and has traveled the world maintaining everything from 757s to J-3s to Bell Jet Rangers in Alaska to Cobra gunships in Vietnam and spent the last 30 years doing mainly GA engine rebuilding and maintenance. He seems to do good work. He insisted on checking the rod bearing journals, NDT ing the rods, new bushings, new big end bearings. I personally observed him torquing the through bolts and cylinder nuts to spec in stages, and double checking them. In all his years of fixing airplanes, he has had one airplane that he worked on crash, and the cause was not related to what he worked on.
So I recently find some articles that Mr. Busch has written and he pretty much makes it sound like if you take more than one cylinder off, or (gasp!!!!) take ALL of them off AT THE SAME TIME, you are DOOMED!
My question is this: is it true that airplanes are falling out of the sky left and right because people made bad decisions and replaced all the cylinders at once on their otherwise serviceable airplane engine?????? With bottom ends on flight school airplanes with my same engine (O320) going to 3500-4000 hours on a regular basis, and his inspection of my engine being OK, I think I made the right choice at a total cost of $4000 vs. $14000 for a major overhaul. The guy who did my work hasn't lost an engine yet in 30 years.
