Seven-foot sickle bar mower for Super C

We are using an I-H seven-foot, PTO sickle bar mower, attached to the two axles. My problem: What is the way to properly adjust the knife sections to the ledger plates? Altho' the mower is cutting reasonably well (very little bunching or binding of grass), the clearance between the knife sections and the ledger plates seems to be far too much to cut as cleanly as they should.

How can the knife blade be adjusted to tilt downward at the front so as to make the knife sections more nearly lay just on top of the ledger plates?

I know there are shims that can be added or removed from under the bar retainers, but neither operation seems to change the tilt of the blade.

Is there a manual for maintenance or adjustment of this mower? Help, please?

After a careful examination of ALL the sickle bar knife blade parts: Hold downs, bearing plates, shims, knife, sections and guards, I was able to reassemble them all, including all the new parts I purchased, correctly. I don't believe that this sickle bar had been correctly assembled in many, many years.

The mower works beautifully! As we my grandson and I) proceeded with assembly, from the outermost holddown in toward the head plate, we continually tested the clearance by operating the pittman by hand. When we finished,although there was some minor resistance, the knife (and bar) operated freely without binding. There was very little or no "free" or play in any direction; up/down or sideways.

But, of most importance, the knife sections were seated very close to the ledger plates. They also had proper registry with the guards. Any section would cut a single blade of grass, held between the knife section and ledger plates!

When I made the first cut with the mower and tractor, I couln't believe how cleanly the mower cut! I first tried it on a patch of grass that had just been cut by a JD Garden Tractor with a mower deck, adjusted for a height of about 3-1/4 to 3-1/2 inches high. The sickle bar was cutting lawn grass as least equal, if not better, than the JD with its mower deck did!

I feel I now qualify as an "expert" in this field and will be willing to help any others that have had a problem with their C-21-M 7-ft sickle bar mowers!

Bob B.