If it's something I'm going to keep for a long time, or a competition engine, these are my minimum mandatory requirements:
Reusing bearings? Never.
Reusing nuts/bolts/studs? Depends which ones. On a redblock, flywheel bolts, head bolts, and any bolts placed under significant stress or load are replaced. Nyloc nuts are replaced. Fasteners not subject to significant loads aren't (e.g. sump pan bolts, etc). Exhaust manifold nuts replaced with VW copper nuts.
Reusing pistons? Depends if a rebore is required, or if there is damage, or the design is crap, then yes. Rings are always replaced. If a rebore is required, new CP pistons and matching rods sourced from JVAB are used, with the nice thick gudgeon pins.
Reusing rods? 9mm rods are never reused. If the bore is okay meaning the pistons are being reused, the replacement 13mm rods are crack tested and shot peened by a shop that is certified for doing aircraft work, not a hot rod shop. Even new rods are crack tested, and shot peened if okay.
Reusing oil pumps? Depends on the age and mileage. If it's a young, high volume Penta / turbo version, measure it according to the book, and give it a new ball and relief spring if the gears are in spec. If it's old or a little one, it gets a brand new Melling M181. In all cases, it gets the iPD drive collar and Penta-spec oil pipe seals when being replaced.
Reusing piston rings? Never.
Reusing other things that you have forgotten? Sorry, my psychic powers don't work. :) But let's guess and talk about other components.
Reuse crankshaft? Generally. It is sent for shot peening though if it passes crack testing. If it shows signs of problems, it's replaced by a Penta crank which is also tested and treated the same way. Then it's linished, and finally balanced with the whole reciprocating assembly including the flywheel.
Camshaft on OHC engines? The cam is checked for wear and replaced only if it's worn, or if it's already planned to be replaced by a better profile.
Camshaft on OHV engines? The cam is generally replaced because it's likely to be worn, and in old-timer engines because there are better profiles available. New lifters are always used with a new cam. Cam bearings are replaced.
Pushrods / rockers on OHV engines? Pushrods are reused if they're straight. Rockers are shot peened. The rocker shaft is examined for wear and straightness. If rules / budget allow for competition engine, go roller rockers.
DOHC tappets? Replaced with new ones. Old ones are disposed of; I do not take risks with interference engines.
Cylinder block? It is decked, line bored, hot tanked, and flushed at absolute minimum.
Welsh plugs / freeze plugs? Replaced with brand new ones.
Felt seals on OHV engines? Replaced with neoprene seals. Prayers and gentlemen's agreements work better at retaining oil in an engine than felt seals.
Cylinder head and valves? The head is crack tested, tested for flatness, bigger valves are installed if required along with the 5 angle valve seat machining and lapping. Old valve springs are replaced. Old or not are tested regardless for equal pressures. Valve stems and guides are checked for wear and the stem seals are replaced of course. Retainers are checked for wear. Chambers are cc'ed, and ports are matched to manifolds and equally to each other.
Timing belt? Replaced with best quality available.
Timing belt tensioners? Replaced with new ones; No exceptions. Old ones are put in the emergency spares pile if SOHC, or disposed of if DOHC.
Water pump? Replaced with brand new Hepu pump. No exceptions. If a Hepu is on the engine, it goes into emergency spares; if anything else, it is disposed of.
Engine sensors? Replaced if old or if the sensor is known for failure; retained if new and age is known.
Crank pulley / harmonic balancer as applicable? Replaced if old and if the type is subject to fatigue; otherwise clean an re-use.
Expensive? Yeah. Overkill? Maybe, but a redblock engine done this way will go, keep going, and survive almost anything, as long as it's maintained, kept oiled and coolant-ed and otherwise maintained, and not abused too crazily.
'Do it once and do it properly' is a mantra which pleases me. That way, since I'm in my twilight years, it will never need to be done again in my lifetime.
jlfents;122119 wroteHowever, I want to go deeper and know why things wear - specifically to a block.
Sure.
How much does one thermal cycle affect a block? Not as much as many heat cycles. See answer below.
How much does numerous thermal cycles affect a block? Old engine blocks tend to better and stronger than new ones, because of the heat cycle process. It was said that years ago, BMW used to used old road car engine blocks for their 1200BHP F1 turbo engines, because the number of heat cycles had settled the metal and so the blocks were less likely to crack.
At what point does a block deform and warp? Usually when a conrod goes through it. :D Seriously though, Volvo cast iron redblocks are not prone to warping as such; however, the blocks do deform at very high RPM, causing them to spit out welsh plugs. It's the alloy heads, rather than the blocks, that tend to warp after they've overheated or when a head gasket has blown.
What causes a block to go out of tolerance? With a redblock? Damage, basically, caused by abuse and lack of basic maintenance.
From what I gather, not always do the journals in the block need to be corrected in terms of alignment? If so, then providing good maintenance and no overheating has taken place then shouldn't the alignment and straighness never go out of whack? The journal alignment doesn't tend to go off, it tends to be a product of the quality of the original manufacture, and what kind of tolerances the maker was prepared let slip through to the showroom. If the alignment is found to be off, it means it wasn't ever that good. Volvo blocks tend to be okay in this respect, but a line boring by a competent machine shop never does any harm. Doing that simply removes the manufacturing tolerances and puts it back to the blueprint spec.
And similiarly, how does the deck flatness change? It doesn't change, either, unless the block is damaged. However, the deck heights of Volvo redblocks hasn't ever been that brilliant out of the box. Sure, they've flat, but the deck heights aren't consistent with the blueprints. This is one area where the competent machine shop can make serious improvements.
Happy to be professionally corrected on any of the above; I am just an enthusiast with big ears and gray hair.
