Ford 640 problems shifting and engaging PTO

[TomIn]

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?

 

[Sean in PA]

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.

 

[TomIn]

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.

 

[sotxbill]

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.

 

[KCTractors]

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.

 

[Ultradog MN]

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.

 

[Eman85]

Is the clutch adjusted properly?

 

[Sean in PA]

Is the clutch adjusted properly?

I asked that earlier and he replied that it hasn't been adjusted in the 20+ years that he's owned it.

 

[Jim.ME]

I asked that earlier and he replied that it hasn't been adjusted in the 20+ years that he's owned it.

Which would seem like the first thing to check/do at this time.

 

[Sean in PA]

Which would seem like the first thing to check/do at this time.

Some people just can't take advice.

 

[TomIn]

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.

 

[Tony Jacobs]

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 .

 

[Tony Jacobs]

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 .

 

[TomIn]

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?

 

[Tony Jacobs]

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?

Well for one you still not have mentioned whether you have a grinding sound with either the transmission or the pto when trying to shift either of them into gear . Which would indicate the clutch being out of adjustment or just plain worn out and there is no adjustment left . That would also give you hard shifting when you try to disengage the pto or when shifting the transmission out of gear because the clutch is NOT fully disengaging . Your assumption of how the clutch works is correct but the spinning or turning of the shafts is part of it also . When the clutch is Properly Adjusted and released (pedal down) All gears and shafts should be completely stopped . When the clutch is released (pedal up and the transmission in neutral) the clutch assembly being attached to the flywheel / engine rotates , because the input shaft of the transmission is splined to the clutch disc it rotates the gear attached to the input shaft which rotates the countershaft which is where the pto gear is driven from on most all transmission type 540rpm PTO’s . So even with the transmission in neutral there is shafts and gears turning / rotating when the engine is running but the tractor is not moving . The rocking of the tractor back and forth to shift either indicates pressure on the transmission shafts created by the clutch not fully disengaging even when the pedal is down , indicating clutch adjustment or wear so there is no adjustment left . The only other possibility if you have NO Grinding of the gears whatsoever at anytime would be RUST . If the tractor is used only say once or twice a year the shifter on both could be getting rusted up from lack of use and slowly be getting harder to use . I do not however think that is your problem but I have seen it before especially on the pto shifter from lack of use .

 

[TomIn]

Well for one you still not have mentioned whether you have a grinding sound with either the transmission or the pto when trying to shift either of them into gear . Which would indicate the clutch being out of adjustment or just plain worn out and there is no adjustment left . That would also give you hard shifting when you try to disengage the pto or when shifting the transmission out of gear because the clutch is NOT fully disengaging . Your assumption of how the clutch works is correct but the spinning or turning of the shafts is part of it also . When the clutch is Properly Adjusted and released (pedal down) All gears and shafts should be completely stopped . When the clutch is released (pedal up and the transmission in neutral) the clutch assembly being attached to the flywheel / engine rotates , because the input shaft of the transmission is splined to the clutch disc it rotates the gear attached to the input shaft which rotates the countershaft which is where the pto gear is driven from on most all transmission type 540rpm PTO’s . So even with the transmission in neutral there is shafts and gears turning / rotating when the engine is running but the tractor is not moving . The rocking of the tractor back and forth to shift either indicates pressure on the transmission shafts created by the clutch not fully disengaging even when the pedal is down , indicating clutch adjustment or wear so there is no adjustment left . The only other possibility if you have NO Grinding of the gears whatsoever at anytime would be RUST . If the tractor is used only say once or twice a year the shifter on both could be getting rusted up from lack of use and slowly be getting harder to use . I do not however think that is your problem but I have seen it before especially on the pto shifter from lack of use .

Sorry for the delay in reporting back. I was down at my country place (where the tractor is located) for the last 2 1/2 weeks. I don't have any grinding sounds when shifting gears or engaging the PTO as long as the tractor is stopped. I checked the clutch adjustment per the manual and it seemed that the free petal movement was about as close to 3/4" as I could measure. The manual seemed to say that both the petal height and free petal movement could be adjusted but my 1955 640 seems to have the same set up as earlier models. My 1955 960 looks the same as the manual's picture. Looking at parts diagrams, the adjusting eye bolt seems to have been used through 1957. Is my reprint manual wrong, or do I have a peculiar or mutt clutch arrangement?

As for the possibility or rust, I use the tractor at least once a week in mowing weather. It sits idle for several months in the winter while I live in the city.

 

[Tony Jacobs]

Sorry for the delay in reporting back. I was down at my country place (where the tractor is located) for the last 2 1/2 weeks. I don't have any grinding sounds when shifting gears or engaging the PTO as long as the tractor is stopped. I checked the clutch adjustment per the manual and it seemed that the free petal movement was about as close to 3/4" as I could measure. The manual seemed to say that both the petal height and free petal movement could be adjusted but my 1955 640 seems to have the same set up as earlier models. My 1955 960 looks the same as the manual's picture. Looking at parts diagrams, the adjusting eye bolt seems to have been used through 1957. Is my reprint manual wrong, or do I have a peculiar or mutt clutch arrangement?

As for the possibility or rust, I use the tractor at least once a week in mowing weather. It sits idle for several months in the winter while I live in the city.

Well provided you are reading the serial numbers correctly , since you didn’t show pictures of them or say what they are I would say your manual may be a later printing but since you didn’t say manual you are referring to I can’t answer that either . The early 4 speed tractors 600/700/800/900 only began in 1954 and have both the clutch shaft and the brake shaft running through the transmission case up until early 1958 601/70/801/901 series tractors . After that the 4 speed clutch linkage became the same as the 5 speed clutch linkage . So your manual is correct for the 5 speed adjustment because those only had one design unlike the 4 speed with the early and later designs . So no there is nothing wrong with your 640 tractor .

 

[Eman85]

. I don't have any grinding sounds when shifting gears or engaging the PTO as long as the tractor is stopped.

That means it's all working correctly, are you trying to shift gears like a vehicle while moving?

 

[TomIn]

That means it's all working correctly, are you trying to shift gears like a vehicle while moving?

In "normal" operation of the tractor I do not attempt to shift gears until the tractor is completely stopped, and there is no grinding of gears. On rare occasions, the tractor gets "hung up" in wet ground and I attempt to rock it back and forth until it is no longer stuck. The tractor is not moving when I shift between forward and reverse, but the rear wheels may not have come to a complete stop.