mk3 crank knife edging, cast tidy up (2017)

Since the main bearings do not have a direct oil feed and they are essentially nested in a blank end recess, it is critical that there is some misting of oil for lubrication.

Besides windage trays, crankcase evacuation (air pump) is the cats pajamas! You see it on NASCAR. With little to no air there is little to no wind..age. Works great for plain bearing engines but could spell trouble if you were very efficient at it with a Commando due to the roller main bearings mentioned above. At one time, Jim Comstock ran an air pump to draw down crankcase pressure on his race bike; I vaguely recall it being a vane type pump driven off the back of the timing chest beneath the carbs. The other benefit of a depressed crankcase pressure is improved piston ring seating and sealing.

Dances with Shrapnel said:

Good looking rebuild! Regarding the polished crankshaft, it's not the goal but the journey. Enjoy!

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I tell myself this everyday. Today I’m talking about the sleeve bearing that is stuck on the sleeve gear. Three days ago it was the bung that dropped into the tank. Thanks for the reminder

Joe Schlaberdowski said:

Is the windage tray just a barrier and how does it come to be properly designed? Is it by cut and try? Mopar had a way to measure the amount of oil in the 'cloud' in a running engine, but not sure how that is done either. Or is that no big deal with a dry sump (thought race engines might be dry sump though). At any rate 20 - 30 hp even a large engine is not insignificant.

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The first windage trays were just that; a tray. But, as they soon found out, all that did was hold a puddle of oil up close to the crank where it could be picked up again. The next iteration was to include angled cutouts that would use the whirlwind from the crank to help direct oil back out to the pan.

The next step up is the scraper, but they have to be custom-fitted if anything deviates from stock (stroke, aftermarket rods and/or bolts, profiled crank cheeks). Here's how one appears on an inline 4-banger:

The scraper is sandwiched between two oil pan gaskets as the oil pan is being installed.

Typically, a dry-sump system will still incorporate a scraper with the return pickup situated next to the scraper, as that's where the bulk of the oil will be ejected to.

Nathan

Mopar used an oil level sensor in the crankcase and internal cameras to observe the phenomena. I used to race Mopars and attended a bunch of their "Direct Connection" seminars. Their tech showed a video tape of the whole thing. It was a real epiphany for me re oiling.

Holy OP thread bump Batman.
Don't overthink it with stock parts, its a basic dry sump engine with little in common with a car crankshaft.

Check everything, set a sensible RPM limit, put the time and shine on the inside.



Don't go near the rods with a motorised polishing mob.