Ford 640 problems shifting and engaging PTO

TomIn

Member
I've owned a 1955 Ford 640 for a little over 20 years. I use it almost exclusively with a finish mower (and no overrunning PTO clutch). In the past couple of years, it has become harder to shift gears and/or engage or disengage the PTO while I am stopped on some occasions. I seem to notice this much more when I am on a slope. What is the likely cause of this issue? How can it be corrected?
 
It could be any of several things and there might be different causes for the shifting issue and the PTO issue. When you try to shift the gears or engage/disengage the PTO, does it grind or does it just not let you move the shifter or PTO handle where you want to move it? It might be that the clutch isn't fully disengaging when you press the pedal down. Have you tried adjusting the clutch pedal linkage according to the manual? It could also be worn internal parts that you would need to take things apart to see. I recommend adding an ORC to the PTO just for safety's sake, but it will also put less stress on the internal PTO drive line in the long run as well.
 
It could be any of several things and there might be different causes for the shifting issue and the PTO issue. When you try to shift the gears or engage/disengage the PTO, does it grind or does it just not let you move the shifter or PTO handle where you want to move it? It might be that the clutch isn't fully disengaging when you press the pedal down. Have you tried adjusting the clutch pedal linkage according to the manual? It could also be worn internal parts that you would need to take things apart to see. I recommend adding an ORC to the PTO just for safety's sake, but it will also put less stress on the internal PTO drive line in the long run as well.
When the PTO and/or shifter are "locked up", neither handle will move more than a tiny amount. I was guessing that something was not disengaging. I haven't tried to adjust the clutch in the 20+ years I've owned it and suspect prior owners weren't any more religious about adjusting things.

I appreciate the safety aspects of using an ORC. However, my ground is a bit rough, and I rarely use anything but first gear. The inertia of a five foot finish mower hasn't created any noticeable issues.
 
I've owned a 1955 Ford 640 for a little over 20 years. I use it almost exclusively with a finish mower (and no overrunning PTO clutch). In the past couple of years, it has become harder to shift gears and/or engage or disengage the PTO while I am stopped on some occasions. I seem to notice this much more when I am on a slope. What is the likely cause of this issue? How can it be corrected?
Non live pto means that the pto is directly connected to the rear end and the spinning or non spinning of the pto is in direct conflict with what the rear end is doing,, ie one is turning and one is still or the mower is spinning making hard to put into gear.
 
I've owned a 1955 Ford 640 for a little over 20 years. I use it almost exclusively with a finish mower (and no overrunning PTO clutch). In the past couple of years, it has become harder to shift gears and/or engage or disengage the PTO while I am stopped on some occasions. I seem to notice this much more when I am on a slope. What is the likely cause of this issue? How can it be corrected?
I would recommend you get a pto over-running clutch. I even use them on the tractors that have a pto clutch brake. I think it saves the pto clutch disks.
 
It could be any of several things and there need to take things apart to see. I recommend adding an ORC to the PTO just for safety's sake, but it will also put less stress on the internal PTO drive line in the long run as well.
I disagree about him needing an ORC Sean.
On a rotary mower/ bush hog with their huge amount of inertia yes.
Even back when I was still running Ford Ns I didnt need an ORC with a finish mower - or post hole digger or cordwood saw.
 
Thanks to all for the advice. I will try adjusting the clutch when the time seems appropriate. Today doesn't seem appropriate since I have a summer cold, the temperatures are forecast for the 90's. the tractor is about 100 miles away, and my ambition seems to dwindle as I approach my 79th birthday.
 
Non live pto means that the pto is directly connected to the rear end and the spinning or non spinning of the pto is in direct conflict with what the rear end is doing,, ie one is turning and one is still or the mower is spinning making hard to put into gear.
Non Live Pto Technically is Transmission Pto and Pto are not connected to the rear end . All Pto wether live or non live are transmission driven . The conflict is the spinning of one side of the pto shaft and not the other . The output side of the pto shaft turning from an attached implement spinning and the transmission side not turning because it is disengaged , OR the output side of the pto shaft NOT turning and the transmission side TURNING because of a incorrectly adjusted Clutch not fully Disengaging and causing the transmission gears to continue turning but not enough to move the tractor . As is the problem in this case . Unless of course the clutch is just plain worn out and there is no longer any adjustment to begin with .
 
I disagree about him needing an ORC Sean.
On a rotary mower/ bush hog with their huge amount of inertia yes.
Even back when I was still running Ford Ns I didnt need an ORC with a finish mower - or post hole digger or cordwood saw.
I completely agree with you Jerry . I have never used an ORC on anything I have ever owned regardless of tractor or implement . I am not saying that there is not a need or an application for one but this isn’t one of them in my opinion either .
 
Non Live Pto Technically is Transmission Pto and Pto are not connected to the rear end . All Pto wether live or non live are transmission driven . The conflict is the spinning of one side of the pto shaft and not the other . The output side of the pto shaft turning from an attached implement spinning and the transmission side not turning because it is disengaged , OR the output side of the pto shaft NOT turning and the transmission side TURNING because of a incorrectly adjusted Clutch not fully Disengaging and causing the transmission gears to continue turning but not enough to move the tractor . As is the problem in this case . Unless of course the clutch is just plain worn out and there is no longer any adjustment to begin with .
i'm still old, sick, 100 miles away from my tractor, and suffering the effects of old age. I'm not an engineer and have never torn down a 70+ year old tractor. What Tony says sounds good to my uneducated mind, but the constant mention of "turning" and/or "spinning" has me a little confused.

I've always thought that the clutch connected (or disconnected) the engine from the transmission. I've also assumed that the transmission "drove" the rear end if the transmission was engaged in one of the gears. If the transmission was not in any of the gears, only gravity would make the rear end turn. (The operating principal of an ORC suggests that inertia from a brush hog could also make the rear end turn when an ORC is not used.)

If I would turn off the engine, there should not be any "turning" or "spinning" caused by the clutch not fully disengaging? My problem seem to be that I can't move the shift handle out of gear until I disengage the PTO, and I can't disengage the PTO while the transmission in gear. Slightly "rocking" the tractor seem to provide enough slack to either disengage the PTO or get the transmission out of gear. When I am sitting on the tractor on a level concrete floor in the pole barn, I can shift my weight back and forward enough to gently rock the tractor. It is more of a challenge when the tractor is on a slope in mud and/or high weeds and I have one foot on the clutch and the other foot on the brakes.

What am I missing?
 
Yesterday's Tractor Forums

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top