I was hoping someone could help me with the timing of the engine balancer on my D47U.  I removed the balancer and rebuild the engine but did not disassemble the balancer.  When I went to reinstall in the instruction in the Cat book are not clear.  I have the timing mark aligned for the gear under the front cover.  I also have the W's aligned on the weights per the instructions.  However where the gear on the shaft connects to the weight there is supposed to be a timing mark on the weight but there is not.  There is only a mark on the gear.  Has anyone ran into this? 

did you bring the engine to top dead centre. it doesnt matter which cylinder. but for simplicity use cyl 1.

okay is there 2 gears on that drive shaft?
if i understand it right one gear meshes with the balance weights the other meshes with idler gear at the front and its mark only matters when doing the cam and fuel pump timing.
the marks that matter are the ones on the balance weights they have to be aligned so they are mating correctly at tdc for any cylinder. you hold their position with the cap screw.

you need to read the section on the timing gears for more info.

This issue is sort of hard to explain. I guess the problem that I am having is in the second picture the "C" does not mate with any other timing mark. The balancer shaft is not 1:1 so even if the A marks line up on the idler gear that doesnt mean that the weights are in the correct position.

The two gears on the drive shaft are fixed/pinned. If the timing marks for the drive gear and idler are matched up and the weight index marks (W) are lined up and piston is at TDC your good to go.

OM, I was thinking if his #3 gears taper pin broke and woodruff key came out (long shot), the balance gears would be off. The 315 I just installed in one of our D4s had a broken tapered pin.