Cockshutt 1650 Hydraulics, location relief valve?

I have a new to me 1650, I believe it's a 1967.
I cannot lift a 1500 bale of hay, it feels like the hydraulics to lift are restricted in some way.
The tilt for the loader has enough power to lift a bales weight, but the loader lift cannot.
I have read for hours posts relating to this, and now am at wits end.
I have adjusted the restrictor valve out, and played with it to no avail.
I have cleaned the filter or element.
Filled with ATF fluid, the hydraulic fluid was low initially.
I spray washed the tractor and cannot find any leaks in the hydraulics.
I have tried to locate the hydraulic relief valve, but am not able to find it, googling it or otherwise.
I am thinking according to my research so far that I will try and locate, clean screen etcetera for the relief valve if someone can point me in the right direction.
Maybe it is sticking??
I'm sure there is information I am missing please keep in mind I am not mechanically inclined, but I do my best.
So idiot proof directions would be needed..
Any help certainly would be appreciated, bought tractor to put 1500lb hay bales out for horses.
Hopefully someone can help, tired and frustrated.

I wouldn't put ATF/ use ATF for the hydraulic system. Use something like a Hy-Tran oil. ATF is to thin maybe your problem. I assume you have a loader on this tractor. Do you have the hoses hooked up in the remotes. If you have a 3000psi gauge put it in one of remotes and dead head it and see what you get for pressure.

Thanks for the reply, unfortunately I don't have a pressure gauge.
I added fluid according to the owners manual.
Now I'm wondering if you are right, and I should drain the fluid.
I still need to locate the relief valve, just for my own relief..

The hoses are hooked up to the remotes.
It has a loader, and PTO.

maybe try new ends and couplers on the loader lift hoses, they do go bad

Which system do you have? Hydralectric? Depth stop?

Well first of all is the hydraulic system the style with a 3 point hitch or is it the style used on wheat land tractors (no 3- point)? Also remember a worn pump and a leaking relief valve will act the same. Do take a coupler and place a pressure gauge in there and tell us what pressure you have. I would use universal hydraulic fluid and remember the 1650 models were introduced 50 year ago and hydraulic oil have changed. Do the pressure check first.

(quoted from post at 05:06:26 09/28/14) Well first of all is the hydraulic system the style with a 3 point hitch or is it the style used on wheat land tractors (no 3- point)? Also remember a worn pump and a leaking relief valve will act the same. Do take a coupler and place a pressure gauge in there and tell us what pressure you have. I would use universal hydraulic fluid and remember the 1650 models were introduced 50 year ago and hydraulic oil have changed. Do the pressure check first.

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There is not a 3 point hitch, I believe it is hydra-electric, I will try and get a pressure gauge.
I am working the next 5 days, so won't be able to get to it til next weekend.
I will pick up some universal hydraulic fluid and try that as well.
Thanks for the advice, I'll post any solutions as i try them.

Do the pressure test before you change the fluid. Do you have a telephone. I am still trying to determine which hydraulic system you have. J.

(quoted from post at 14:54:12 09/28/14) Do the pressure test before you change the fluid. Do you have a telephone. I am still trying to determine which hydraulic system you have. J.

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I am including some pics which may help identify the hydraulic system, as I'm not sure of the answer.

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