Making the sauage
Nerd alert. Way more information about a PT6A-67B engine than most sane people would want to know.
Another update on my engine overhaul for anyone that is interested. I am documenting this partly for my own learning and as a reference for others looking at a PT6 overhaul in their future. Probably about 1000% more than most people want or need to know!.
Some photos of components about ready for reassembly after inspection and repair (when needed).
Some photos of components about ready for reassembly after inspection and repair (when needed).
Combustion liner...
Exhaust housing...
Compressor turbine (CT) vane...
Gas generator (GG) case with freshly applied protective coating. This coating is Aeroguard which is blue versus the original Sermatel coating which was silver. Might take me a while to get used to seeing the big expanse of blue every pre-flight. The accessory gear box will attach to the aft end...
Inside the gas generator case...
The re-assembled power section with the reduction gearbox attached. This section contains the two power turbines (PTs), the reduction gearbox, ITT bus assembly (temperature sensing...thermocouples, bus and harness), power turbine vanes, and the exhaust housing...
Top view of the power section...
My brand new fuel control unit (FCU). I opted to get a new and improved FCU (including improved bellows with no life limit) rather than overhauling the original...
Compressor bleed valve...
The gas generator section with the accessory pad installed (including the new FCU)...
And...drum roll...the fully assembled engine on a test jig ready to go into the testing cell for test runs...
Right now I am running about 3% over the original overhaul quote. There is a relatively small amount of cost to be determined based on the runs in the test stand. For example, during a test stand run they will compare the actual ITT to the indicated ITT and see if any thermocouples need to be replaced. They also do vibration testing which almost always passes (they tell me), but that is about the last thing that could cause a delay if the vibration tests fail.
Assuming the test stand runs go OK, the plan is to truck the engine tomorrow to the Pilatus service center (SC) in Thunder Bay and they will re-install and test again (lots of ground runs and a test flight). The overhaul shop is sending one of their technicians to the SC to assist with the rigging and to help gain some time on the schedule (we are slightly behind). An SC pilot will deliver it to me in Austin on Sunday (two days behind the original schedule). Sort of glad he will be putting the first 4-5 hours on the plane with the fresh overhaul!
So, within a few percent we are on-time and on-budget. Can't complain about that too much.
More to follow.