51 JD B Crankshaft timing mark

Ok, i am working on bring this 51 John Deere B back
to life. I have gone over the crankshaft gear with a
fine tooth comb and am not able to locate the timing
mark. Would anyone have a picture of a crank gear
timing mark that I could reference? Even a
description of the location, something like.."On the
main bearing side of the gear, count three teeth
counter clockwise from the tooth that lines up with
the keyway slot" Thanks a lot!

Well, I thought someone would have a by the book answer by now, but I can tell you what I've done in the same situation.

Put #1 cylinder at TDC and establish a mark somewhere on the crank or flywheel so you can find TDC again.

Put the cam in with the #1 set of lobes in the overlap position, just guess at it for now.

Temporary the gear on, or the chain, or engage the timing gears where you think the cam is in overlap.

Rotate the crank back and forth watching the lifters. When both lifters are equal height, one going up, the other going down, note the TDC mark. If it's lined up, or as close as it will get going one gear tooth either way, you're in time.

If the flywheel cover is removed, if I'm not mistaken as I'm more familiar with open flywheel unstyled tractors, there are still a couple marks on the flywheel. One is Left Hand Impulse (LHI) and the other is Left Hand Exhaust (LHE).

Now if the flywheel is on the correct crankshaft spline:

When the LHI mark is in the 3 o clock position (mark on side of tractor) the Left Piston is at TDC.

When the LHE is at 3 o clock, the left cylinders exhaust valve should just be taking up slack and getting ready to open and would as soon as the flywheel is turned a bit more. IE LHE at 3 o clock means the left cylinders exhaust valve is just ready to begin to open.

To set the camshaft gear correct to the crank gear, have the flywheel at LHE at 3 o clock and then set the cam gear so the left side exhaust valves is tightening up ready to open.

NO WARRANTY ON THIS I'm not as familiar with covered flywheel tractors but I think this is still correct........

Also the governor shaft gear is set to the cam gear so at LHI, left piston at TDC, the open female slot in governor shaft end (where mag or distributor mates) is flat horizontal fore n aft.

John T That's the best I got on this lol