How does a Trans PTO work?

[HåkanTh]

From Operators manual:

Transmission PTO
The transmission type of PTO (available on Ford 2000, 3000 and 4000 tractors) is operated by engaging the clutch, and will stop turning when the clutch pedal is depressed.
The drive to the PTO is engaged by depressing the clutch pedal and moving the PTO lever situated on the left-hand side of the rear transmission, fully rearwards. To disengage the PTO depress the clutch and move the lever to the forward position.
The table below shows the recommended engine speeds to obtain the PTO speed of 540±10 rpm.

Trans--------Model------Engine rpm
6/7 speed...Ford 2/3000....1800
8 speed......Ford 2/3000....1600
8 speed......Ford 4000.......1800


Live PTO
Live PTO (available on Ford 2000 and 3000 tractors) operates in a similar manner to 'Transmission' PTO except that an intermediate clutch pedal position stops the tractor without stopping the PTO shaft.
To operate the PTO shaft, depress the clutch pedal completely and move the PTO shift lever fully rearwards. Engage the PTO by slowly releasing the clutch pedal until the shaft begins to turn. Allow the PTO shaft to reach the desired speed then slowly engage power to the rear wheels by releasing the clutch for the remainder of its travel. Control the PTO speed and tractor forward travel by use of the throttle and by selecting the right gear.
The clutch operating rod clevis pin can be used in two positions. Select the rear position in the clevis to operate and control the drive to the PTO and the tractor.
When the PTO is not in use put the pin in the forward position.
To obtain a PTO speed of 540±10 rpm an engine speed setting of 1800 rpm is required.


Independent PTO
(Available only on Ford 4000 and 5000)

[krazymatt]

Thanks for all the info. It looks as if I'll be needing to adjust my clutch or separate the tractor to investigate further.

[krazymatt]

If adjustment doesn't work, will I have to replace the pressure plate too or just the clutch disc?

It's weird because my transmission works great and my clutch engages pretty normal, doesn't engage high on the pedal travel, nor does it slip under heavy load. I'm crossing my fingers it's just mal-adjusted or a worn linkage or something. So I want to adjust so my pedal is at the highest point?--or how do I make sure I adjust it properly?

Thanks.

[jdemaris]

Originally Posted by krazymatt

If adjustment doesn't work, will I have to replace the pressure plate too or just the clutch disc?

It's weird because my transmission works great and my clutch engages pretty normal, doesn't engage high on the pedal travel, nor does it slip under heavy load. I'm crossing my fingers it's just mal-adjusted or a worn linkage or something. So I want to adjust so my pedal is at the highest point?--or how do I make sure I adjust it properly?

Thanks.

Need more info on what setup your tractor has. If your engine clutch works fine, and you can shift gears with no bad clash when the clutch pedal is in - it sounds like you've got a dual-clutch tractor with live PTO and a stuck PTO clutch disk.

That is a fairly common problem with dual clutch setups. Engine clutch works OK but PTO clutch is stuck in "engaged" position. Sometimes it's just and adjustment, but often it's just plain stuck.

Like I said, if your wheel-drive works well and you can shift fine when the clutch is down - that same clutch cannot be your PTO problem. So, it sounds like you've got two clutches.

Now if you had a wheel-drive PTO, it is supposed to clash IF you try to shift while the tractor is rollling. But, I'm not even sure it was available on your tractor. It's a common feature on many other British tractors though, as well on many USA Deere and Henry (AKA Harry) Ferguson tractors.

Is your tractor a hi-low range trans model?

By the way, I find non-live PTOs to be near useless in Ford tractors. They often come with the four-speed trans setup which is also useless for certain tasks. Way too fast in 1st and reverse. Four speed was dropped mid-70s, and a 3 speed with a hi-low range took its place. Similar to what the Ferguson TO-35s had.

2000s and 3000s before July of 1968 came with four speeds or eight speeds.
2000s and 3000s mid 1968 up to 1975 came with four, six, and eight speeds along with 10 speed hydraulic-clutch transmissions.

After 1975, I'm not sure.

My 1964 4000 Ford does have a wheel-drive PTO. Ford called it a "ground speed" PTO.

[krazymatt]

Originally Posted by jdemaris

Need more info on what setup your tractor has. If your engine clutch works fine, and you can shift gears with no bad clash when the clutch pedal is in - it sounds like you've got a dual-clutch tractor with live PTO and a stuck PTO clutch disk.

That is a fairly common problem with dual clutch setups. Engine clutch works OK but PTO clutch is stuck in "engaged" position. Sometimes it's just and adjustment, but often it's just plain stuck.

Like I said, if your wheel-drive works well and you can shift fine when the clutch is down - that same clutch cannot be your PTO problem. So, it sounds like you've got two clutches.

Now if you had a wheel-drive PTO, it is supposed to clash IF you try to shift while the tractor is rollling. But, I'm not even sure it was available on your tractor. It's a common feature on many other British tractors though, as well on many USA Deere and Henry (AKA Harry) Ferguson tractors.

Is your tractor a hi-low range trans model?

By the way, I find non-live PTOs to be near useless in Ford tractors. They often come with the four-speed trans setup which is also useless for certain tasks. Way too fast in 1st and reverse. Four speed was dropped mid-70s, and a 3 speed with a hi-low range took its place. Similar to what the Ferguson TO-35s had.

2000s and 3000s before July of 1968 came with four speeds or eight speeds.
2000s and 3000s mid 1968 up to 1975 came with four, six, and eight speeds along with 10 speed hydraulic-clutch transmissions.

After 1975, I'm not sure.

My 1964 4000 Ford does have a wheel-drive PTO. Ford called it a "ground speed" PTO.

According to my tractor serial numbers, my tractor is a 1974 Ford 3000 British model. Agricultural, 8X2 (High-Low) Transmission and it is a "Trans PTO".

[jdemaris]

Originally Posted by krazymatt

According to my tractor serial numbers, my tractor is a 1974 Ford 3000 British model. Agricultural, 8X2 (High-Low) Transmission and it is a "Trans PTO".

Trans has to be a 4, a 3 X 2, or a 4 X 2.

I assume you've got the 4 X 2, i.e. four speed box against a two speed box that yields 8 speeds forward and 2 speeds in reverse.

If you have a single-clutch "tranmssion driven" PTO, that PTO is disconnected from the engine - just as the wheel drive is when the clutch pedal is down.

So, if I understand your description of events properly, something here does not make sense.

If the trans gears shift fine and don't drag or clash when the pedal is down, the PTO can't clash. Now, if the PTO is generally hard to engage or disaengage anytime - clutch in or out, that's a different story.

If the PTO DOES clash, and the trans does NOT, then the PTO is getting rotational power even when that trans-input is not moving. That cannot happen unless you've got a dual-clutch, twin-input shaft tractor.

Does the clutch pedal feel smooth all the way when you push it in? If a live PTO setup with a dual clutch, the pedal should feel the same for only about half-way down, and then you feel increased resistance as the pedal starts to disengage the second clutch.

[krazymatt]

Originally Posted by jdemaris

Trans has to be a 4, a 3 X 2, or a 4 X 2.

I assume you've got the 4 X 2, i.e. four speed box against a two speed box that yields 8 speeds forward and 2 speeds in reverse.

If you have a single-clutch "tranmssion driven" PTO, that PTO is disconnected from the engine - just as the wheel drive is when the clutch pedal is down.

So, if I understand your description of events properly, something here does not make sense.

If the trans gears shift fine and don't drag or clash when the pedal is down, the PTO can't clash. Now, if the PTO is generally hard to engage or disaengage anytime - clutch in or out, that's a different story.

If the PTO DOES clash, and the trans does NOT, then the PTO is getting rotational power even when that trans-input is not moving. That cannot happen unless you've got a dual-clutch, twin-input shaft tractor.

Does the clutch pedal feel smooth all the way when you push it in? If a live PTO setup with a dual clutch, the pedal should feel the same for only about half-way down, and then you feel increased resistance as the pedal starts to disengage the second clutch.

I get what you're saying, that it's acting like a dual clutch with a bad pto clutch or bad adjustment. When I bought the tractor and went to look at it I could shift the pto in and out with the clutch in and the pto would stop when the clutch was depressed. It's with the Brush Hog attached that I was having to grind the PTO shifter last week. I had never hooked up a drive shaft to it yet. Is there a method to ID the back half of the tractor? I suppose someone could've swapped in a rear half off a dual clutch? I'll double check the tractor serial number again.

[Jerry/MT]

Originally Posted by krazymatt

Yeah, It doesn't bother me much as long as it works. The only thing I'll use the PTO for is bush hogging. A ORC will take care of any safety issues. Does the ORC usually stay with the bush hog or implement when it's off or on the tractor? Come to think of it I need to check and see if there' s not one on the bush hog that came with the tractor. I haven't used it yet and I noticed it had a very different drive shaft hookup. It didn't have the spring with pin; it had a round colar looking mechanism. I've never seen a driveshaft hookup like it. Maybe if I'm lucky there's one on that bush hog drive shaft.

You only need an ORC on a transmission driven PTO system when you have a high inertia implement being driven by the pto shaft. That means like a rotary cuttter, a rototiller, etc. (for example pumps for sprayers or auxilliary hydraulic pumps don't need an orc.)

What happens is that the inertia of the implement begins providing torque from the inertia of the rotating parts to the drive wheels by the pto shaft through the driveline. Stepping on the clutch does not stop the process but the orc will. It only allows torque to be transmitted from the pto to the implement and not vice versa. It's kind of a torque diode.

[krazymatt]

Originally Posted by Jerry/MT

You only need an ORC on a transmission driven PTO system when you have a high inertia implement being driven by the pto shaft. That means like a rotary cuttter, a rototiller, etc. (for example pumps for sprayers or auxilliary hydraulic pumps don't need an orc.)

What happens is that the inertia of the implement begins providing torque from the inertia of the rotating parts to the drive wheels by the pto shaft through the driveline. Stepping on the clutch does not stop the process but the orc will. It only allows torque to be transmitted from the pto to the implement and not vice versa. It's kind of a torque diode.

But if my clutch was working properly it should stop the pto from pushing the tractor forward if the clutch was depressed right?

[krazymatt]

I tried adjusting the clutch today by making the linkage shorter. I'm not sure if this is correct but it didn't help anything. I am starting to think I need a clutch. The tractor does NOT have two seperate holes for adjustment. I was reading on a seperate post that it's better to have someone re line and rebuild my clutch disc and pressure plate instead of buying an aftermarket? Any tips on splitting the tractor? Thanks...

[Nouveau Redneck]

According to your model number you do not have live PTO. If you can shift the PTO lever without grinding when the PTO has nothing connected to it, but it grinds when you have the brush hog connected, I suspect something is loose in the PTO drive line allowing the weight of the brush hog to cause the engagement gears to go out of alignment. With the engine off, try to move the PTO shaft in and out, up and down and left to right by hand. If it has any play in it then you may need to go inside to correct whatever is allowing the free play.

[JohnW]

Originally Posted by krazymatt

But if my clutch was working properly it should stop the pto from pushing the tractor forward if the clutch was depressed right?

NO, it will NOT stop the PTo from pushing your tractor that is why you need the ORC.

[krazymatt]

I checked the pto shaft yesterday for play. It has no side to side play, and in and out play it has like an 1/16 of an inch if that. When I engage the pto and it is turning, shouldn't depressing the clutch stop the pto when no implements are on the pto?

[Jerry/MT]

Originally Posted by krazymatt

But if my clutch was working properly it should stop the pto from pushing the tractor forward if the clutch was depressed right?

It is working properly! There is nothing you can do to "adjust it out"!

The early Fords(9N, 2N, 8N) and the early Ferguson's (TO-20, TE-20 and TO-30) all had transmission driven pto's. I believe the non DeLuxe models of the TO-35 also had them. So this is a common issue for them. Ther were probably other. I'm surprised your 3000 has that. I thought the "newer" 1000 Series Fords had live pto.

The Pto is driven through the transmission not through a second shaft from the engine like a live or independent pto. It "hard linked" to the drive line that drives the rear wheels so disconnecting the engine from the transmission via the clutch doesn't do any thing to that part of the drive line. Only an ORC will keep the inertia of a pto implement from driving the machine forward. it's just a sprag clutch that transmits torque one way to the implment and ratchets when torque from the implement tries to drive the rear wheels.

[Nouveau Redneck]

I thought the "newer" 1000 Series Fords had live pto.

The "newer" ('65-'75) "1000" series Fords had multiple options on what PTO you could get. You could get them with no PTO, transmission PTO (single clutch), live PTO (double clutch) and independent PTO (separate hydraulic clutch not related to the clutch pedal at all).

shouldn't depressing the clutch stop the pto when no implements are on the pto?

Not with transmission PTO. Stopping the tractor's forward (or rearward if in reverse) motion by pressing in the clutch and pressing the brakes until the tractor comes to a complete stop is the only thing that will stop the PTO completely. Have you been trying to engage the PTO lever while the tractor is still moving with the clutch in? If so, that is why it is grinding. You have to come to a complete stop to engage or disengage the PTO with a transmission driven PTO to guarantee that it's not going to grind.