Lost all hydraulics on my 4630 John Deere tractor

[Needhelp]

Changed all filter and screen
Added new oil still nothing screen was dirty but no metal shavings

 

[Doc]

Maybe the pump.

 

[Needhelp]

that’s what I am hoping not wrong if anyone knows anything else I can try before I look at pump

 

[Doc]

Other than a leak in the line the only thing I can think of it could be is the pump. Sorry, hope it's something simpler.

 

[bczoom]

I don't know the particulars but I believe there's a stroke control valve on the bottom of the pump. If it got stuck, that may be a cause. Keep track of how many turns you do on it but try running it all the way in then back out to see if that does something for you. I "think" it's an Allen head bolt.

 

[bczoom]

Might want to do an internet search for the valve on the pump. Looks like it's spring loaded so if you decide to pull that all the way out, watch for parts that are spring loaded.

 

[bczoom]

Being as your tractor is nearly 50 years old, go to yesterdaystractors.com and do a search for your issue. There's some good people and posts over there that may help.