stringfellow
Active Member
I'm overhauling my IO-540-C4B5 currently under the guidance of my IA. Everything (bottom end, rocker arms, various accessory drives, etc) is at the machine shop being inspected and overhauled. It is a well known engine shop in the Portland area.
However, I've taken on the compliance stuff myself, and I was studying up on SBs and SIs this evening and ran across Service Instruction 1454A. I'm of the opinion that while I'm not necessary beholden to the manufacturer bulletins and instructions, they exist for a reason so I might as well try.
My engine was built new in 1976 and is a first run with ~2400 hours, so I'm pretty sure it has the rocker arms superseded in this instruction.
What i am trying to figure out is if this is a mandatory part replacement at overhaul, or just a "if you are replacing rocker arms, using this new part number" kind of S.I.
Mine appeared fine and the shop stated they would rebush them. They would tell me if they were a suggested replacement item at overhaul, right?
Thanks
However, I've taken on the compliance stuff myself, and I was studying up on SBs and SIs this evening and ran across Service Instruction 1454A. I'm of the opinion that while I'm not necessary beholden to the manufacturer bulletins and instructions, they exist for a reason so I might as well try.
My engine was built new in 1976 and is a first run with ~2400 hours, so I'm pretty sure it has the rocker arms superseded in this instruction.
What i am trying to figure out is if this is a mandatory part replacement at overhaul, or just a "if you are replacing rocker arms, using this new part number" kind of S.I.
Mine appeared fine and the shop stated they would rebush them. They would tell me if they were a suggested replacement item at overhaul, right?
Thanks
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