Getting started

Here is the update on my PT6A-67B overhaul.

Engine arrived at the overhaul facility on May 18 and disassembly began.

As of June 13, this is my engine in bits-and-pieces!

Some of the pieces after being cleaned, inspected and repaired as needed...

After the full tear down and analysis, I received a 10 page "engine condition report" detailing the condition of every major part of the engine and recommended repairs or replacements. Here is a sample of the report to give a sense of the information provided.

Basically, they provide photos of anything needing replacement rather than repair. They said the engine was very clean and showed no evidence of operational mishandling. I was sure I had handled it properly, but I bought it with 1,200 hours so I could not be certain about the prior owner. The only somewhat unusual item needing replacement were 10 compressor turbine ("CT") blades (out of a total of about 45) that showed some evidence of cracking (the smaller line in the photo below is what they say is the defect).

Overall, a pretty clean overhaul with the CT blades above being the only surprise. They say replacement of CT blades is common on a second run overhaul, but not so common on a first run.  Guess that is why you do overhauls. 

The final cost of the overhaul looks like it will be about 5% more than the original estimate which is better than horror stories I have heard of overhaul costs ballooning 50% or more over the estimate.  That includes a brand-new upgraded fuel control unit (FCU) and a brand new second stage power turbine (PT2). The PT2 could have gone another 1,500 hours until its 5,000 hour life limit, but PWC provides a financial incentive to replace it at overhaul. The FCU could have been overhauled at less cost than replacing it with new, but I wanted the improved FCU. For one thing, the bellows in the new FCU have no life limit unlike the 4,000 hour life limit for the bellows in my current FCU.

All that (including the new PT2 and FCU) adds up about $109/hour or $118/hour including the overhaul related items performed by the service center and not the overhaul shop (engine removal and replacement, new engine mounts, etc.). Including my hot section at mid-life, the total is about $125/hour.  I had been budgeting $130/hour, so I am OK with the results.  If I had done a minimalist overhaul (reinstalled the old PT2 and overhauled the FCU instead of replacing it) the cost would have been reduced by about $15-$20/hour.

They promised a 40 day turn on the overhaul and say there is no reason they can't hit it. Should have my bird back by July 7.