Tractor Hydraulics help/advice

[Ag 89]

When I bought my property, I made sure I got the tractor in the deal. Its a 1999 John Deere 4600. The hydraulics on the loader now move very slow and are weak. They will not pick up the front end of the tractor. I know the curl cylinders are leaking internally because they drift quickly. Steering does fine except will catch at low engine speeds if tractor is not rolling. 3 point hesitates but then lifts the box blade fine and does not drift. I had a guy out to look at it and he said control valve and would order and come back. That was 5 weeks ago and he doesn't return my calls. I have lost patience with him and will move on to greener pastures.
I am not 100% convinced he is correct and am concerned about the pump. I don't want to just tackle ordering the control valve and put it in and find out that now I need a pump. Control valve is dealer only part and about 600 bucks, pump is about 1500. My choices are, do that or load the tractor and take it to the dealer in Kerrville. I am leaning toward biting the bullet and taking to dealer, but thought I would ask the green screen about opinions on best option. Thanks in advance.

[Walker]

I'd change the hydraulic filter first.

[Ag 89]

I'd change the hydraulic filter first.

Already changed filter/cleaned screen and changed oil.

[Radar]

You would need to check the pressure coming out of pump, there should be a port on it to put a pressure gauge. If the pump is making correct pressure the control valve is likely bad.

[60 Deluxe]

Get on tractorbynet.com or tractorforum.com and ask that question. There are some lifetime mechanics on those forums that can pinpoint the problem from what you have described, or they will ask you more questions. It may be that some o-ring has broken internally that is allowing a massive oil flow by-pass. I've been pretty amazed at some of internet diagnosing that I've read on those two sites.

[Quackerbox]

Probably the valve. They can be tested and rebuilt. Find a repair shop in your area or haul it to tomball. My womans shop can fix it and are actually slow at the moment.

[Ag 89]

Thanks for the input! The tractor guy actually called me back and is coming Tuesday to reseal the curl cylinders and put in a control valve. I will keep the tractorbynet.com and tractorfourm.com on my list of future references. I will update afterward.

[wytex]

Have you added any trans hydraulic fluid lately ? Everything moves slower when it gets low.
Also this is supposed to work great on leaks: https://www.lucasoil.com/product/hyd...ter-stop-leak/

[Ag 89]

Update: Boss man came out and found the actual problem. Kinked pressure line (Lines are metal). I must have hit it on something, but do not remember when or how. My guess is a rock got thrown up into it. Will be back Friday with new line. He took the cylinders to the shop to reseal.

[Big_gun]

sometimes hoses are cheaper... good deal bet its back and running like before soon