# 1963 ford 4000 Select o speed, pto will not disengage



## fordtruckguy123 (Aug 31, 2011)

I have a 1963 ford 4000 with the select o speed transmission and approx 2600 hours on it. When I bought this tractor it had been sitting for quite a while and I got it running and have made a few repairs. Since then I have had a flail mower attached to it and ran it a few times, at that time the Pto would engage and disengage with the pull out knob next to the sos control. Now the pto will not disengage with that knob or when the clutch is depressed. I am unsure of what the problem is, any Ideas?


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## sixbales (May 18, 2011)

I know nothing about SOS transmissions, so I posed your question on a forum where I know that some of the guys are experts. Here is what they said (so far):

Sean in PA: 
The pedal that looks like a clutch pedal on an S-O-S tractor is called the inching pedal, and it has nothing to do with the PTO. The PTO on the S-O-S models is called "independent" for a reason, it operates completely independent of the rest of the transmission. The only thing that controls it is the PTO handle next to the gear selector lever on the dash board.

The PTO is driven from a separate clutch inside the transmission that does not have a brake, so it relies on lack of any impetus to continue moving as the means to "stop" it when you push the handle in to stop it. If there's no implement attached to the PTO, most of them will continue to turn, but without any real power behind the movement, and if you have a brush hog or other heavy implement attached, it will stop. If you don't have an implement attached, you can test it by pressing a 2x4 or 2x6 against the side of the PTO shaft to see if that stops it. If it stops with an implement or from the 2x, then it's fine. If it still runs with power behind it such that the implement won't stop running or the 2x won't stop it, the first thing that you should do is get a service manual and follow the instructions in there to adjust the PTO control handle cable, and if that doesn't fix it then splitting the tractor and seeing what that clutch needs is the only thing that can be done. Keep in mind that some parts are no longer available. Mine has turned with power since I got the tractor and since I only use it for brush hog work, I haven't bothered to tear into it. I just disconnect the PTO shaft when I'm not using the brush hog, and connect it when I want to use it. 

Dean:
Does it "disengage" when the knob is fully inward and the PTO has a load on it?

sixbales:
He had a flail mower attached to it, and ran it a few times, and the PTO would engage and disengage with knob. 
Now the PTO will no longer disengage with the knob. 

nw_bearcat:
May have just loosened up the mower. Mine rarely stops spinning when lifted, but stops when hits grass


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## sixbales (May 18, 2011)

Further comment below from Sean in PA. He adjusted his PTO handle and I asked him how he did it.. You need to get a shop manual for your tractor. Ebay usually has them for sale:

According to the book (it might be different for your tractor based on model & year), you undo the nut holding the cable housing to the back of the handle housing, then undo the big nut holding the handle housing to the dashboard. Then you turn the whole handle housing so the cable rotates inside the cable housing, on mine it's a reverse thread on the cable so that counter clock wise tightens it in and clock wise loosens it up. Adjust it so that when everything is tightened down again, the handle moves a total of between 1 3/8" and 1 7/16" from all the way in to fully pulled out. I had originally set mine to about 3/4", so pushing it all of the way in from all of the way out wasn't moving the control valve inside the transmission far enough. Again, depending on your friend's model and year, the exact measurement he needs may be different, but that measurement I gave is for all 1965 to 1975 2000, 3000, & 4000 series Select-O-Speed transmissions.


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## Bedford24 (Sep 28, 2011)

Here is a website dedicated to these transmissions Ford Tractor Select-O-Speed Troubleshooting


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