Ford 3600 new double clutch, PTO doesnt work

rwspear

New User
1980 Ford 3600 with Q Cab, 6700 hrs runs great

Had a new double clutch put in my machine 3 weeks ago at the dealer, clutch was stuck and inop and way worn out ($3000 for all that work). Dealer mechanic said no problems inside, went back together perfectly but noticed PTO shaft does not spin when engaged but absolutely sure nothing is causing that in the clutch. Guy says he has worked on 3600s for about 30 years and nothing abnormal about this one. I went to the dealer mid-job and saw it myself while split and he showed me things and that all looked good, other than the clutch. Now that I have it back, the tractor goes into gear and drives fine through all gears/ranges, however, I try to engage the PTO and handle moves and feels to engage/move the collars inside but no action on the PTO shaft when let the clutch out.

I have replaced the PTO shaft, shift collar, input shaft collar, shift fork, shift cover, shift handle, detent spring and ball, rear PTO seal, pto shaft bearing and PTO shaft sleeve on his recommendation as he thought the problem was the either the fork or collars. When I took the old shaft out, noticed that PTO shaft collar looked worn and the shaft had two areas on the splines that looked damaged or possibly welded? Input shaft looked just fine. No noises at all when moving the tractor, drives like new.

Put all that back together, with no luck getting the PTO to function at any position of the clutch. Later, I noticed that the clutch linkage is adjusted all the way down (rod is as short as possibly can get). Im confused as to how the PTO clutch would not work while the trans/drive clutch would (should disengage trans first as pedal is depressed, then the PTO clutch). Also noticed the clutch arm is not vertical with the clutch pedal out (like other tractors I have seen in pictures) but sits about 15 degrees off vertical pointed towards the back of the tractor with the clutch pedal out. The arm looks like it has had some welding on it around the area where it sits on the clutch shaft, perhaps it slipped some and that was a fix for it by the previous owner.

Question: is this an adjustment issue of the linkage or likely more serious internal problems? I really cant explain how it can have trans drive but not PTO action with the double clutch when the clutch pedal is released. Seems to me that you would expect the PTO clutch to work but not the trans if the clutch was far out of adjustment or something was wrong with the clutch?

Really, really not looking to split this tractor again at the clutch just to find the issue is not there (I believe the mechanic, he had the tractor for 2 months working on it). The linkage adjustment and arm position, just looking at it, seem a little odd, like the clutch is partly depressed, but not sure how that would work as I explained. With all the internal shafts (that I could access at least) looking good, no broken pieces found, no metal shavings, etc and replacing all the parts that potentially could break or cause probs in the PTO, Im at a loss as what to do next. I don't think breaking an input shaft or countershaft inside the trans would be the problem as I don't hear any noises or grinding at all.

Any help or things I can do to potentially diagnose this machine's issues are much appreciated, Im stuck now on this and really need to get this PTO turning as Im in Texas and grass down here starts growing again in a month or so! Thanks!
 
Is it possible that the fork that moves the shift collar from engage to disengage does not have a grip on the collar itself? I'm not much help but if I paid $3,000 to have my tractor repaired and it was returned to me with the PTO not working, I would make the machine a suppository for that mechanic.
 
There is a fixture made for building the 2 stage clutch on.
While building the clutch there are settings made in the
process to make it work properly, if these settings are not done
properly the clutch will not work properly. I'm not saying it
wasn't done right, just something to look into if all else fails
 
The adjustment on the clutch rod is for setting the clutch pedal free play. Do you have 1" of free play and can you feel both stages of the clutch when you depress the clutch?

Mark
 
I do have about 1" of free play on the pedal. I disconnected the rod this afternoon and tried to turn the lever back and forth to see what sounds, etc. it made. I can definitely feel the trans stage and then a second, smaller, 'click' in the handle and I assume that's the PTO clutch when I move the lever as far as it goes (clutch in).

Im still at a loss, drove the tractor this afternoon with no problems whatsoever, except no pto.....
 
With the engine off engage the pto and see if you can turn the shaft with a pliers. If you can turn it something is not connected, for it should have to turn the engine over and that will not turn easy. If that happens pull the side cover and make sure the coupling is meshed if not move it by hand to see if it will mesh. If not that is where your problem is. If that all turns it is in your clutch area and it could be a spline problem into the clutch.
 
I think you have a problem with the dealer that repaired the tractor. No way in hell would we send a tractor out that just had a clutch installed that the pto was not working, and you have been charged about $1500 too much if the clutch was all that was installed!!!
Boss
 
I did try and engage the PTO and then, with engine off, turn the PTO shaft. It has good resistance, but I can still turn it by hand. I disengaged and turned it and, as expected, it turned very easily. I was also expecting that with it engaged you could not turn it as you were then turning against the motor.

The collars do engage, but last night I was looking at the I&T manual and saw that there is a little snap ring that goes on the input shaft collar. I noticed that this ring seems to be missing on mine as the collars engage, but when engaged the two can slide up and down as there is nothing holding the input shaft collar in one place. Is that snap ring causing all of this? The snap ring was not present when I replaced the collars a couple of days ago.

I would think that because the input and output shafts are very close to one another, end to end, that it would not really matter as neither can move enough to fall off their respective shafts? It didn't seem to me that either collar could move enough to disengage. I did take off the cover and made sure the collars were firmly engaged and locked into each other and tried again, but no progress. Once I did this, then I found the PTO was harder to spin, but still could do it by hand.

Also, the input shaft splines seem to be in good shape as well. The PTO shaft collar that came out had some scoring on the groove where the shift fork sits. Wonder if something got bound up and broke that little ring?
 

Pressure plate not adjusted correctly. The fact the main disc is working shows the throwout bearing is working. either pressure plate is screwed up or the pto disc is broken.

Take it back...
 
Another question: I just noticed (looking at the new Holland exploded diagram of the clutch and thinking about all this) that the 1980 Ford 3600 I have shows a triangular 11" 10-spline trans clutch disc with a round 8 1/2" 29 spline PTO disc. What was put on the tractor, which was also shows as fitting a 1980 Ford 3600 tractor (supposedly), was a round 11" 10 spline transmission clutch disc and a round 8 1/2" 29 spline PTO disc. Is the round transmission disc only for a transmission PTO and really not for a dual stage clutch?? Im wondering if this is my problem, that the triangular clutch for transmission somehow affects the PTO clutch disc and since mine is round and not triangular, is this preventing the proper operation of the PTO clutch?? Any input would be very helpful on this!
 
I don't see how the Trans clutch being round would have anything to do with the PTO. Based on what you have done to this point I agree with sotxbill something is wrong in the clutch, disc in backwards if that's even possible, broke hub ??? Take it back.
 
As an update, I talked to both the clutch dealer and also the mechanic from the dealer I had the work done. The clutch came already built and adjusted, on a jig, and was done properly. I talked for a long time with the mechanic, who was very kind and honest in attempt to help me understand what could be going wrong and he seemed to think the clutch was not the problem as nothing abnormal about the install and the throwout bearing, etc was functioning. He suggested opening the shift lever cover again and having someone bump the starter several times while I watched to see if the input shaft turned at all. He said that even if the clutch were completely out of adjustment, without any load on the shaft (implement) it should turn as it would make just a little contact since it is new and would turn the shaft or at least try to. He thought that even if it was just only slightly engaged, something should at least try and move. I did try this today and no movement what-so-ever in the input shaft after several turns of the starter. He also said check the pedal and lever travel of the clutch levers, etc which I all checked out OK. So we then discussed that there is a very high probability that something is broken internal with the pto shaft itself, since in a live pto it is hollow with the transmission input shaft inside. He said if the PTO shaft was torqued he had worked on several of these tractors with the gears on the countershaft stripped completely off or the gears themselves fractured to pieces. He also has seen examples of the input shaft off the clutch breaking where the outer pto input shaft is torqued and split while the transmission shaft is unscathed.

Either way, the fix is a lot more than splitting and the clutch. This tractor has cab, etc. and would essentially have to be fully dismantled to get to this shaft or try and fix it. Given the age of this thing, I don't think it is worth it. Guess Ill just have to live with a non-PTO tractor and go to self powered or ground (wheel) powered implements (mowers, etc.).

Has anyone else had something like this happen? Would like to see just how common or uncommon this might be and what the result might have been if a fix was attempted.....
 

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