Ford 7710 won't move but has good DP pressure

I have a Ford 7710 series 2. It was well maintained but was left set for a couple years. One day I started it only to discover that the clutch was stuck to the flywheel. With the clutch pedal pushed down, I started slipping it in and out of gear and holding the brake to try and get it to pop loose, but had no luck. My buddy got in the tractor and got a little more radical with shifter, two hands on the gearshift and was really ripping it , and might not have had the clutch pushed in......well, something broke. The clutch broke free, but the tractor would barely move, kinda like the clutch was slipping. And within a couple minutes the tractor would not move at all.

Well I got the tractor in the garage now, and checked the DP pressure with all possible combinations of fwd, pto, and DP possible.... pressure is constant 180 psi. So I'm kinda stumped. Also I noticed if I have transfercase gearshift in low range or reverse and shift transmission back and forth between 1st and 3rd without actually putting it into gear the tractor kinda tried to move a couple inches.

Also, if I press the gearshift into 1st or 3rd gear I can feel the teeth on the gears clicking by, if I push a little harder it will stop the gears. Also pushing the clutch pedal stops the gears in about 2 to 3 seconds.

Does anyone have any ideas what might have broken? I immediately thought DP, but with 180 psi, that seems unlikely. Could it be something with shifter linkage? Or Maybe twisted center out of clutch or something? I hate to split it if I don't have to.

Thanks for your help
Dusty

The fact that the gears slow to a stop after the clutch pedal is depressed makes me think the clutch is
doing what it should. DP breakage is almost unheard of, so I'm going to say that something let loose inside
the tranny. At first I was thinking a broken shift fork, but if that were the case, it should still move in
at least some of the gears. Possibly it has broken a shift collar inside the trans. Either way, I'm thinking
you're gonna need to pull the top cover off of the trans and take a peek inside.

If you're not convinced that the clutch is working, you could always pull the starter out and take a peek
inside the bellhousing with a mirror and a flashlight. If indeed the clutch disc center is broken out, you
should be able to see that.

Clutch plate broke? maybe friction disc came loose from the plate, or stripped out splines would be my guess.

I have a 7710 II synchromesh trans and had trouble with the plastic bushings in the external shift linkage slipping out of place If the shifter does not shift right look there first I replaced them with brass ones

Thanks for the help, I'll start with removing the starter to see if I can see any damage, and then go from there. Thanks again for the input everybody!

I would suspect the output from the dual power going into the transmission. External spline on dual power shaft and internal spline on transmission main shaft. Fixed
one last summer that was acting just as you described.

I pulled the starter off and tried to inspect the clutch for damage....but I couldn't see very well through the hole with flashlight and inspection mirror. So I split the tractor and rolled it apart, as you predicted, the clutch is fine.

I had an idea to check the DP. I took the line off the valve on right side of the tractor and pressurized it with my air compressor. I think if I pressurize the DP valve, you shouldn't be able to turn the input shaft of the transmission...I could hear the clutchs working when I pressurized it, but the input shaft still turned freely.

So, knowing that, do you still think u should take the top off the transmission to look for problems with shift collar, shift fork, etc. Or do you think I should concentrate on the DP.

Also, I guess the only way to get top off the transmission is to raise the cab....is that correct?

I pulled the starter off and tried to inspect the clutch for damage....but I couldn't see very well through the hole with flashlight and inspection mirror. So I split the tractor and rolled it apart, as you predicted, the clutch is fine.
I had an idea to check the DP. I took the line off the valve on right side of the tractor and pressurized it with my air compressor. I think if I pressurize the DP valve, you shouldn't be able to turn the input shaft of the transmission...I could hear the clutchs working when I pressurized it, but the input shaft still turned freely.

So, knowing that, do you still think u should take the top off the transmission to look for problems with shift collar, shift fork, etc. Or do you think I should concentrate on the DP.

Also, I guess the only way to get top off the transmission is to raise the cab....is that correct?

(quoted from post at 02:45:55 03/05/19) I pulled the starter off and tried to inspect the clutch for damage....but I couldn't see very well through the hole with flashlight and inspection mirror. So I split the tractor and rolled it apart, as you predicted, the clutch is fine.
I had an idea to check the DP. I took the line off the valve on right side of the tractor and pressurized it with my air compressor. I think if I pressurize the DP valve, you shouldn't be able to turn the input shaft of the transmission...I could hear the clutchs working when I pressurized it, but the input shaft still turned freely.

So, knowing that, do you still think u should take the top off the transmission to look for problems with shift collar, shift fork, etc. Or do you think I should concentrate on the DP.

Also, I guess the only way to get top off the transmission is to raise the cab....is that correct?

Click to expand...

I would take Sunbeams advice before pulling the cab.

I also agree with sunbeams advice.
I have a 6610 with same trans and also have a cab.
The plastic shift bushings have gone bad in both shifters, also that trans has a clutch interlock that will not allow you to shift gears without having the clutch pedal pushed down.
If he tried to shift gears without using the clutch it's messed up something in the shift linkage, the plastic bushings would be the first thing to check.

Hey Bern, turns out you were right. The problem was in the transmission. The main shaft shift fork has 2 brass pins the move the shift collar back and forth. Both of those brass pins were completely tore up. So the shift fork moved, but nothing moved with it. I got the shift rails slid back and replaced those brass pins today. Slid transmission and differential back together. Going to lower cab and try to finish reassembley tomorrow. Thank you for your help.

Should have left the gorilla out of the cab.

When our 9000 didn t move it was the dual power clutch housing that blew the back out of.