Maybe I am too protective or fussy with things, but when I go to start the direct start 17a  I always release the compression and roll it over till I get oil pressure heat it roll it over again then start it. That’s part of the reason they lasted so long they did not have dry starts like we have with modern engines today.  17afarmer

Hi, 17AFarmer.
Then you'd HATE the D9T we have here on the ranch. You turn the key on and to the "Start" position and nothing happens except for a humming sound for maybe as much as 10 seconds and suddenly the starter begins turning the diesel and it fires right up - - - - - complete with operating oil pressure - which is what the humming sound is all about, priming the engine oil pump before starting.

Bleeding the fuel system after changing fuel filters is a real PITA too - hold down a switch in the little cabinet where the fuel filters reside for a few seconds until the resultant buzzing stops - - - - and then turn the key to "Start". Itza terrible life but somebody's GOTTA doowitt' LOL.

Just my 0.02.

Those Videos posted earlier are something to watch -- I would not be able to sit down if I treated those machines that way! Certainly would have been looking for a place with more cushion that a burlap sack on those horsehair seats with springs poking through!
Start the Starting Engine (electric starter - what is that device? Only a bent piece of steel or a rope was used) - don't let it get hot but do warm it up - engage the pinion to ring gear, compression released on the main diesel, get main turning, check fuel pressure and oil pressure, give it a chance to make sure it is ciruculating oil and disengage compression release. Warm those cylinders, open fuel (throttle) if it does not fire right up, shut fuel off and continue warming, try again. A very light "shot" of starting fluid was a big help but certainly nothing like spraying the air filter till it ran all over the place. That will lock the diesel and does tend to wash all lube away from the cylinders. (Starting Fluid was a luxury item, most did not have it in the tool box)
The starting engine was always allowed to run out of fuel after shutting the supply off. Saved a lot of trouble.

Deas - RE: D9T starting and bleeding procedures --- do you suppose when the battery is low or the computer has a hic-cup, a poor ol dum buldozer operator could get going?
Caterpillar just using some of the technology that was prevalent in WWII (in-line) engines --- Packard, Rolls Royce Merlin for example.
This new stuff has made so many advances - yet I seriously doubt it will be running when it is as old as these machines we cut our teeth on.

I think you can still buy aftermarket priming pumps that will pressurize the oil system, my dad saw a AC. HD 21 a guy put an army surplus pump on to prime the engine. they ought to put them on at the factory.

try priming the oil for a mirrlees k series 6cy marine engine. keep stroking that hand pump till you see oil flow in the sight glasses about 40 to 50 strokes or so. or a napier deltic 60 strokes you have to change hands part way.