Workshop Listers! We have discussed operations slightly out of order, as the military static method calls for crank assembly before Balancing, but many of you may choose other methods. 

Crank assembly procedures differ slightly with different kinds of wheels. Cast wheels are reputed to fragment, so you are on your own with those, also. At least magnaflux them.  If you choose nodular iron wheels such as of Truit and Osborn origin, you probably couldn't get the mainshafts crooked if you tried: It was my experience with them that both (H-D) shafts installed deadnuts at first torque. S&S flywheels are forged and springy: Mallet taps tend to send components back to the natural 'set' of the tapers. Still, the machined accuracy of their products is impeccable. Indian "Z" wheels, unless n.o.s., should have scrupulous inspection and preparation of the tapers, keyways, etc, before attempting shaft assembly. A light lapp for 'reading' for chattermarks or a raised edge at the keyway is an Inspection step; Using your lathe tailstock to press your wheel against a gulleted shaft full of 'Thixogenous Greasemix" spinning in the headstock until it stops wobbling is probably a Machining step I bet! 

If everything is hygienic, the mainshafts should set into their tapers snugly, and the nut acts as the assembly aid to pull it into the taper with a squeeze like a nail into an oak timber. I merely put the wheel in my press to hold it as I bring the nut up snug. The wheel sits upright directly on the parallel members of the press table truss, with the ram gently pressing upon the outer circumference. Then it's off to the centers to read the wheels' wobble. Marking the high/low sides, I then remove it from centers and place it shaft down into an anvil made of a drill bushing of the appropriate size welded to a plate for a stand. This protects the shaft and its centers as I 'discipline' it in the marked direction with a light lead mallet. Back to the centers for a read, and back to the press for retorque. I repeat this as necessary until true and up to full torque. I believe the military manual presents this as 100 ft/lbs (for the crankpin), which really isn't much (I like 120-125). 

Use the nut locks if you wish (there's always Loctite, but remember deleting the locks raises your balance factor ever so slightly), then it's time to assemble the rods for truing the whole crank. The same attention to detail must be given to the crankpin tapers as the mainshafts'. 

At this point one must select the flywashers for appropriate rod endplay. I prefer more to less, as torquing the pin draws this parameter tighter, and can bind the rods, particularly if the races have been replaced. It is common to find that the miniscule pins have been sheared, or new 
washers must be notched to match where they have been replaced. 

Final flywheel truing: Again I use my press to hold the loosely assembled wheels, this time placing the ram simultaneously on both wheels, perpendicular to the crankpin. With the parallel truss members beneath for a jig, I find that after a snug-up, I rarely have the shafts more than .007" runout on a side, usually only .002" to .004", and the misalignment is usually in plane with the pin: wide at 6 o'clock and tight at 12. This is easily within massagable range. Indeed, it is adviseable to refrain from any malleting at all beyond the mainshaft step. Here a large C-clamp and a pair of small crowbars can be used to close or open the gap between wheels opposite the pin. You may have to go back and forth, or maybe tap sideways (always out of the inspection centers) at a high spot to achieve true. Again the assembly goes back to the press for more nut torque. The wheels skew slightly each time the nuts are tightened, but the press seems to keep the mis-alignment in the 12 o'clock to 6 o'clock plane. A few re-trues and re-torques and a final massage at full torque should hopefully leave you at less than .001" runout on each mainshaft. 

Compared to modern milwaukie wheels with huge tapers, Chief Z wheels are quite manageable, and no one should be afraid to give this a try. 

P.S. Some ancient Greek probably said something like: An authority unquestioned is probably wrong. Don't let me get away with this so easily. 
 

From: Guy <guyiii@home.com> 
You could also lighten the new pistons (carefully) to maintain equivalence of wts.... 

From: Tim Pickering <Pickering_T@usp.ac.fj> 
Just one query that you may want to expand upon, and that is:  
What happens if the shaft centres are unreliable?  Do you have any alternative methods as a backup?  For example, can one use a truing stand that has sleeves which fit over the mainshaft O.D. to find the centres, rather than use the dimple in the end of the shafts (if these have been knackered by past butchery)?  Is it a common occurrence for shaft centres to be unreliable, in your experience? 
  
From: "Cotten" <Liberty@npoint.net> 
Usually if the end centres are bad, the rest of the shafts are worse. Replacement, if possible, is usually the only option. 

From: indianjohn <johnmarg@pilot.infi.net> 
As nearly all habitual tinkerers have a drill press available, I will describe the way my friend trued flywheels in one. It seems a bit awkward to me but worked well for him and is certainly usable for the one or two uses the average owner would have for a truing stand. 

It uses a center mounted in a plate that was secured to the press table so that the center stood with the point up. Another center was chucked in the spindle and the two alined to the same axis.The flywheel was mounted in the vertical plane with one shaft standing in the lower center and the other shaft secured by the center in the spindle. The wheel was then hand rotated between the centers while measuring runout with indicators mounted in universal magnetic mounts. After the high spots were located and marked, the wheels were removed and carried out of sight of the customer where they were proffessionally bashed with a heavy lead maul and then the process was repeated until satisfactory results were achieved. Crude but effective. My friend died about ten years ago but some of the engines he built using this method are still in daily use. Good luck with whatever method you attempt. 

 
Although this inspection stand is massive and has a spring loaded tailstock, it is no more effective than a common lathe. Two indicators are a luxury.