# 8N PTO won't engage



## OTR

Howdy all. I have a 1948 or '49 8N that I've been using for brush clearing. I took a break from clearing last weekend, and when I came back, the PTO lever would not move far enough for the PTO to engage. I tried rocking the tractor, barely engaging the clutch, etc. in the hopes that it was just a temporary gear alignment issue.

From everything I've read online, a twisted PTO shaft appears to be a common cause of this. I removed the PTO shaft and inspected it, it looks perfectly fine. Furthermore, while it was removed, I tried moving the PTO lever, and it was *still only moving about half as far as it should* - so I'm pretty sure whatever is going on has nothing to do with the shaft itself.

The lever is in the right spot in relation to the rod that it is supposed to move. I am able to take the lever off and move the rod by hand as well.

At this point, I'm thinking there must be something blocking the movement of the rod that the PTO lever moves. I can't see anything causing a blockage. I assume the blockage must be in the housing pictured below (picture is recycled from another user)?

Any suggestions would be appreciated. I'm handy with a wrench but completely new to tractors.










Could it maybe relate to parts 19 and 20 in the below diagram?


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## HarveyW

Hello OTR, welcome to the tractor forum.

Excellent presentation of your problem. There is a possibility that the detent ball has worn down, allowing the detent spring to become lodged in the detent groove, limiting movement.

Please post back your findings...


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## OTR

So I took the cover under the seat off and was able to see what is shown below. Ultra-high res is available under each picture.

Looking down from where the seat would be, right of picture is front of tractor, with the PTO lever disengaged (looks like I would expect):









Click here for super-sized resolution

Same camera location, but with the PTO lever engaged as far as it will go (I assume the... synchro?... should be about 1/2 inch further forward (to the right of the image):









Click here for super-sized resolution

Now, with the camera peeking in the right side inspection plate, I notice that I can see the hole for the detent ball, but I don't actually see the detent ball itself. I would have expected it to be poking halfway out the top of the hole that I've circled - is that expectation correct?









Click here for super-sized resolution

So, I assume at this point, I need to take out that housing - the one pictured in my first post above. I can't really find any instructions online about how to do that. I assume removing the bottom plate is part of it, but that appears to be connected to the... pump? Any help here would be greatly appreciated. Thanks all!


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## OTR

Okay, as best I can tell, I take out the PTO shaft, then drop the bottom plate, which the pump will be attached to. I assume I can then access the four bolts that appear to hold the synchro housing on and take that off, after which I should be able to figure out what is going on inside it. If I am missing anything important here, someone please let me know.

Unfortunately, I am out of time for this weekend, so to be continued in a week...


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## sixbales

OTR,

Have a look at current post in the Ford/New Holland section of this forum entitled "*PTO issues on 1964 Ford 2000*" written by Nash10032 for another issue that prevents shifting of the PTO lever. 

See also attached parts diagram.


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## sixbales

Attached is a "cut-away" picture of an N series tractor, illustrating the PTO drive train, compliments of Smith's old ford tractors site.


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## OTR

Well guys, I found the problem. The bolt that connects to the transmission spline snapped, and the bolt head, washer, and lock washer were preventing the PTO shifter from moving all the way forward. Aside from the bolt, washer, and lock washer, everything else appears to be unharmed. 

Bolt - part 3 in below diagram
Lock washer - part 4
Washer - part 5










I'm a little curious as to what would cause that bolt to snap, considering that it's not really under any load - it's just to hold the spline-to-synchro adapter in place. The washer is also bent out like a cone, from what I can tell it's supposed to be flat. Very odd. 

Naturally, I don't own a drill that can fit in there to drill out the broken bolt, so I'm off to the store. Thanks, all, for the help and suggestions.


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## sixbales

Outstanding report. Thanks for sharing. That's the kind of repair that makes you feel good!


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## OTR

Not much of an update, but just checking back in to report that the tractor was put back together and is running great. The PTO engages better than it did when I bought the tractor earlier this summer.


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