720 forage chopper question

I just picked up a 720 chopper from a family acquaintance, and have a question on it. It's been sitting for quite a few years, so grease is kind of hardened and chains are rusty and stuff like that. But it's in like next to new condition, because it hasn't seen 100 acres of cutting. I did the general servicing and stuff before I kicked the PTO on, and first time everything ran. Second time I tried it the cylinder wouldn't turn. Knew it was in the over running clutch, so I took that apart, and the dogs were stuck down due to old grease. A good cleaning with solvent, and scraping out the cogs inside of the hub should do the trick. But what is baffling me a little, is that there are no springs to engage the dogs (push them outward) Is that normal, and they just rely on centrifugal force, or are there some springs missing?
I am about positive that no one prior to me ever had it apart. It was a one owner machine, bought at an allis dealer in Terry Montana in 1973. The original book that I got with it said a price of something like 4300 and some odd dollars, but the guy I got it from said he paid 3800 for it. Came with a windrow pickup head and a two row 30 inch corn head. The knife sharpener has never been used, and knives aren't bad. Also, if anyone has some NOS parts for it, let me know. As of right now, don't think that we need anything, but planning ahead (unless there are some over running clutch dog springs that I am missing, lol)A parts book/service manual would probably be beneficial, if someone would happen to have either or for sale. I am thinking that since it was bought in 73, and my 200 is a 73, they might go together well. Hopefully by the weekend or next week, we'll put her to work picking up some oats/barly/rye mix that was planted close to the place, and is well over waist high on me. Also, if anyone has run one of these much, and has some good advice for me, that would be great. Thanks, Darrel

You should get a hold of mikez. He has some nod forage harvester parts

dr p wrote: You should get a hold of mikez. He has some nod forage harvester parts

I have PM'ed MikeZ. I need to find part numbers in order for him to check out if he has a part or not
After getting everything cleaned up and inspected, I have come to the conclusion that springs were never in there, and are not required.
I still am hoping to verify that with a parts diagram, but that's my best guess as of now. Thanks, Darrel

They are full on harvesters. It should be able to cut it into 3/8” bits