You really do not hear about many chain failures on the 615, 616, 617 series engine, at least not on this board. I suspect that chain failures are predominately caused by infrequent oil changes and generally poor/bad/non-existent maintenance practices. Something that, if you admitted to doing around here, would merit an immediate whack on the hand.

Lilly's chain had 267,000 on it with about 9° of elongation when I replaced it 'on principle', and just to be able to say I'd done it too. FWIW, the banana rail is a gold-plated PITA to get out. After inspecting it, I decided that it wasn't worn enough to warrant changing. IMHO, that particular part must be made from ailen materials found at the Roswell site to withstand 250,000+ miles of operation and exhibit not one whit of appreciable wear.

FWIW, wholesale for the chain is somewhere between $80-$110, the master link is about of bucks and the tensioner and thermostat housing gaskets are another $2-$3.

It's not a hard job (motor mounts are tougher) but is tedious and time consuming. Also, it is imperative that you remove the rail tensioner before rolling in the new chain. Once the chain is in, replace the tensioner and 'reset' according to the FSM's instructions.

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Never a dull moment at Berry Hill Farm.