F22D mystery knob under seat

[NickBlade]

I've had my F22D for a couple of months and am figuring out what most of the knobs, levers, and lights are for - thanks to much help from you guys. One mystery is the round knob below the seat (not under as I said in the title). It looks like a hydraulic valve that has four English words among all the Japanese - Open Close Fast Slow. I don't even know which of those four it is set on (where you do read it?).

What's this guy for?

 

[284 International]

It is probably the valve that controls the flow out of the lift cylinder. Screwing the valve in (clockwise facing the knob) should slow the descent rate of the lift arms. Screwing it in fully seals the cylinder. Be Darryl, because one can damage components trying to operate the lift if the valve is closed, so be sure to only operate the lift with it partially open.

This feature is useful for slowing heavy heavy implements' fall, or speeding up those lighter attachments.

As you likely have inferred, it is not an on/off system, but a continuum. If your heavy disk or mower keeps crashing into the ground when you lower it, screw the knob in half a turn or so, and try again. If a light auger will hardly drop, unscrew it the same amount.

 

[winston1]

Not for sure, but I believe that is to control the speed your 3 point descends or if you close it all the way clockwise it will lock the 3 point at whatever height you have it at. Older Yanmars valve like this was only used to lock the 3 point but I'm pretty sure your f series the valve is also used for slowing descent.

 

[California]

The older Yanmars had a large knob under your crotch that should be full open or full closed. The manual says it is used to lock a back implement in the full-up position to work on it. It chokes off the return line from the lift cylinder. I've been told that driving around with an implement raised with the valve locked, will overstress and break something because the fluid has no relief valve available to that closed system. Then there was a second, small valve in the side of the transmission to control rate of descent. It sounds like your F22D's valve combines these separate functions.

 

[NickBlade]

International, Winston, California, I think that you all got it. I have been running with the valve fully open. I closed it today and the 3-pt was locked. I opened it slightly and the hitch came down reallllly slowly. All the way open and it came down faster. The confusing thing for me is that to the right of the seat next to the 3-pt control lever is a another lever with the numbers 1 - 10. This controls the decent rate for the 3-pt. Plus the control lever has a manual lockout that would also keep the 3-pt raised. So I'm not sure what more the knob does, except provide the ability to lock the 3-pt at any given height, rather than all the way up.

What am I missing ... ?

 

[284 International]

It is possible that the F22 has a draft control lever. I'm not sure if that machine has it or not. It may need a special, matched tiller from Yanmar for a cable actuation, or it may be a draft control as conventional US market machines have.

Draft control manages the amount of force on the tractor by lifting and lowering the implement in response to the force applied to the sensors. Yanmar has special cable attachments to accomplish this somehow; I'm basically unfamiliar with their configuration. If you are able, sharing some photographs may be helpful and interesting.

 

[NickBlade]

Thanks,

According to this recent post, http://www.tractorbynet.com/forums/yanmar/246266-warning-light.html#post2868671, it might be draft control for an implement.

I will shoot some pics tomorrow when it is light.

 

[California]

I think that knob under the front of the seat is intended to be foolproof safe holding the implement up (although I wouldn't count on it for my personal safety!). Alternately your lift-and-hold lever and descent-rate lever are just for operating the tractor, and could move the implement unexpectedly if you bumped the linkage during maintenance work on the tractor. Sort of like the difference between shifting your car to Park (provides some safety) vs putting your foot on the brake (ordinary operation). That's a poor example but I think it is roughly comparable to what you described. Now if your additional levers are instead for draft control (physical linkage) or are related to the proprietary electrical draft system, then my simile is irrelevant.

 

[winston1]

The lever to the right is the draft control lever. I have a post in the thread attached my NickBlade and there is a thread attached in that post showing Mickey_Fx's draft control. He is the only one I know of that has the draft control and tilt controls working as the Japanese intended. My old YM2002D has the draft control lever but I do not have the necessary cables, etc to hook it up. Mine doesn't have the numbers as the newer F series but works the same. http://www.tractorbynet.com/forums/yanmar/105695-auto-tiller-controls.html

The upper end of the lever where lever the spring is attached is the cable hook up point on my YM2002D. Your F22 will have something similiar.

 

[NickBlade]

Well, I'm a thinking that this isn't draft control on the F22D, but something more like a descent-rate lever, like what California was talking about. It is physically next to the lift-and-hold lever. But if so, why have two controls for the same thing? The hydraulic knob provides a much larger range of descent rates (like course control) but is harder to reach and harder to "dial in" the right setting. The lever provides a much more narrow range of descent rates, based on what the knob is set on, but is easier to get to and very precise when dialing in the rate (fine control?).

The hydraulic valve has a complete shutoff to lock the hitch, but so does the lever, which has a mechanical lock, although you can only lock the lever in the fully raised position.

What do you think?

Both levers,lift and hold unlocked
Both levers, lift and hold locked

Knob below seat