VW bus owner: I have my engine case, crankshaft, and flywheel assembled. No camshaft, no distributor drive, no connecting rods. The case halves are clamped with the six large bolts (only), torqued to spec.
The crank endplay is set to 0.003". The bearings and journals are coated with assembly lube and motor oil.
The crank turns easily and smoothly, yet there is one spot in the rotation with just a little more resistance than the rest. The crank won't "coast" through this spot at a very slow speed.
Is this expected / normal?
Intelligent Tinkering: It's possibly a bit of work debris, a thread of cleaning rag or or something like that on a bearing surface, but it could be a pinched or off-round bearing too, or an off-round journal that has been "hammered" and that wants a line bore. The engine turns. That's something. You could take a flying chance that it is actually debris AND softer material than the bearing and so will get better once started and run. You'll know if you turn the crank pulley later, once it's installed and run. You'll feel it, and you know what it feels like already. VWs are renowned for being able to run and give service for long periods with internal damage that would fry a less tolerant engine in minutes. Or, and this is the "right" answer, you can take everything back apart and look for someplace on one or more bearing surfaces with discoloration or other signs. Pinched bearings can be ground on the ends (with fine wet-and-dry Emory cloth) to make them fit better. Biting the bullet like this is wearying and isn't easy, but it will pay off. I find that I get more at skilled and dismantling and mantling complex assemblies if I have to repeat steps, and it always goes faster than you would think. Engineer's blue can be used to find binding and pinched bearings that don't show obvious signs of damage. If you don't find obvious damage, rebuild to this stage again with blue, then dismantle again and you'll find it.
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