4630 hydraulic/ transmission issues

[Jdtank122]

Not a JD man, but I would straighten the shaft as best I could, then smooth the edges of the "worn" spot (though it looks to have been stripped not worn), and see if i could turn the pump from outside. Are there any nicks or dents in the bent part showing impact? I would not use the existing shaft except as a picket pin. Jim

The bent part is smooth as can be. When it was in the tractor I could turn the shaft with a pair of pliars very easily

 

[used red MN]

I don’t know exactly how far that hex engages in the flywheel drive end. It doesn’t look like it is bent enough to pull it out and disengage it. It does look like there is a rounded off section of the hex, so that may have been what made the pump stop. I personally would want to verify the differential pin is still in its proper position, something bent that shaft. Look at this video at 8:30. 4430 trans video It’s a 4430 but for this purpose it is close enough. Although the differential is not exactly in its final position if you look at the hollow shaft in front of it you get a pretty good idea of how close the diff pin runs to where the hex shaft runs. I would suggest you get an endoscope for your phone to look in there and check it over. Here is a link to an example you can get a decent one for $25 - $35. Example endoscope That one has a 7.9 mm diameter which is a little under 3/8” should go in that hole easily. You may have to tape it to a 9 wire to help guide it to what you want to see.

 

[rockcreek4630]

Bend doesn't appear as severe when completely removed from tractor. I don't understand why there's more than one worn spot where shaft fits in trans pump gear hex . If it was under my care due to wear spots I'd replace that hex shaft.
.View attachment 68495

I have seen this before the shaft was not removed when split and got bent when it was rolled back together pushing the shaft back making to ware marks.

 

[wore out]

I don’t understand that either, I’m going to order a new shaft, I’ll will post here when I try it, thank you so much for the help. It’s greatly appreciated

There's no reason the shaft would have bent in that area unless the differential pin smacked it. (Unless someone put it together with a bent shaft the last time.)

Originally you wrote "sounded like I ran over some metal", that seems to indicate more has happened than just the hex shaft stripping inside the transmission pump gear.

Time to take the rear cover or lift mechanism off and have a look.

Even if all else is OK, likely the hex bore inside the transmission pump gear is stripped out, or almost so.

 

[wore out]

I have seen this before the shaft was not removed when split and got bent when it was rolled back together pushing the shaft back making to ware marks.

That's a very good point, RC!

To the O.P., do you have any idea when the tractor may have been "split" last, and how many hours on it since that was done?

 

[Tx Jim]

wore out
Please explain what you're referring to when you stated remove "left mechanism"?? I understand one needs to remove rockshaft housing to view trans pump. But I don't know what left mechanism you referred to. Maybe you meant "lift mechanism" & Spellcheck thought otherwise!

 

[tim s]

There's no reason the shaft would have bent in that area unless the differential pin smacked it. (Unless someone put it together with a bent shaft the last time.)

Originally you wrote "sounded like I ran over some metal", that seems to indicate more has happened than just the hex shaft stripping inside the transmission pump gear.

Time to take the rear cover or left mechanism off and have a look.

Even if all else is OK, likely the hex bore inside the transmission pump gear is stripped out, or almost so.

My vote is with you worn out,,sounds like the diff failed and knocked the back of the transmission pump off..

 

[wore out]

wore out
Please explain what you're referring to when you stated remove "left mechanism"?? I understand one needs to remove rockshaft housing to view trans pump. But I don't know what left mechanism you referred to. Maybe you meant "lift mechanism" & Spellcheck thought otherwise!

"Maybe you meant "lift mechanism"

Yep, I'll fix it, thanks!

 

[Jdtank122]

I don’t know exactly how far that hex engages in the flywheel drive end. It doesn’t look like it is bent enough to pull it out and disengage it. It does look like there is a rounded off section of the hex, so that may have been what made the pump stop. I personally would want to verify the differential pin is still in its proper position, something bent that shaft. Look at this video at 8:30. 4430 trans video It’s a 4430 but for this purpose it is close enough. Although the differential is not exactly in its final position if you look at the hollow shaft in front of it you get a pretty good idea of how close the diff pin runs to where the hex shaft runs. I would suggest you get an endoscope for your phone to look in there and check it over. Here is a link to an example you can get a decent one for $25 - $35. Example endoscope That one has a 7.9 mm diameter which is a little under 3/8” should go in that hole easily. You may have to tape it to a 9 wire to help guide it to what you want to see.

 

[Jdtank122]

Thank you so much for attaching that video, gives me a better idea of what I’m looking at. Thank you for the advice about the endoscope! That’s very affordable. I’ll buy one while I’m waiting on new shaft to get here. Thanks!!

 

[Jdtank122]

I have seen this before the shaft was not removed when split and got bent when it was rolled back together pushing the shaft back making to ware marks.

The tractor was split about 7 years ago, flywheel bolts broke

 

[Jdtank122]

There's no reason the shaft would have bent in that area unless the differential pin smacked it. (Unless someone put it together with a bent shaft the last time.)

Originally you wrote "sounded like I ran over some metal", that seems to indicate more has happened than just the hex shaft stripping inside the transmission pump gear.

Time to take the rear cover or lift mechanism off and have a look.

Even if all else is OK, likely the hex bore inside the transmission pump gear is stripped out, or almost so.

Yes I agree the noise I heard had to be something more. Thank you for those pictures! Gives me a idea of what I’m looking at

 

[Jdtank122]

That's a very good point, RC!

To the O.P., do you have any idea when the tractor may have been "split" last, and how many hours on it since that was done?

The tractor was split about 7 years ago. Flywheel bolts came out. I would say I’ve put a little over 2,000 hrs on it since then

 

[used red MN]

Thank you so much for attaching that video, gives me a better idea of what I’m looking at. Thank you for the advice about the endoscope! That’s very affordable. I’ll buy one while I’m waiting on new shaft to get here. Thanks!!

Probably want the tractor in a spot it can be rolled easily. I suppose you could pull it a bit with another tractor or pickup. Since a couple have said a differential failure can get into the pump itself that is probably what you will find. Not sure how long you intend to keep this tractor but you will want to look into upgrading the differential from the 2 pinion style. See discussion in this link. JD diff update info
Not sure where you are but I would suggest you call Don’s Tractor Salvage in KS. Don’s They are also on Facebook.

 

[tim s]

My money is still on a failed differential...