Sorry.....Another Hydraulic question.

(quoted from post at 13:43:54 08/08/14) My hydraulics work great until I'm out on the tractor for a bit in the hot Texas heat. Then when I try to lift my brush hog it comes up fairly slow. I can rev the engine and it goes up "almost" all the way and when I want it, it goes down just fine. Again when just starting out the 3 point hitch works just fine until about 15-20 minutes of brush hogging. Had the pump cleaned out and they added new fluid and they told me if it does this again I could try a heavier hydraulic oil because the age of the tractor.
Does this sound right?
Thanks for any help you can give

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(quoted from post at 14:27:09 08/08/14) Thanks OldHokie for the quick answer, Yes, the bush hog will leak down after I shut off the tractor. You can watch it very slowly leak down.
Does this mean that it needs a whole new pump and how much would one pay to have it rebuilt?
Would the heavier oil hold me over till after the growing season? That way I'd have the time to have it torn down and do any other maintaince it might need then.

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(quoted from post at 16:08:27 08/08/14) It leaks down when you turn the tractor off or clutch or pto off. How long does that take? If it comes down in just a few seconds your pump might not be too bad. You may just have a leak. Also, what kind of hyd oil did they put in?

I'm no expert, but I had the same problems just a few months ago. Mine would be slow to lift, sometimes not coming up at all until I gave it some more rpms. I replaced the oil and fixed the leaks and now my lift works great.

Take the inspection cover off where your dipstick is and look in there with a flashlight. Do this with your mower on (pto disconnected) and see if you can see any oil leaks.

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(quoted from post at 16:55:05 08/09/14)

(quoted from post at 16:08:27 08/08/14) It leaks down when you turn the tractor off or clutch or pto off. How long does that take? If it comes down in just a few seconds your pump might not be too bad. You may just have a leak. Also, what kind of hyd oil did they put in?

I'm no expert, but I had the same problems just a few months ago. Mine would be slow to lift, sometimes not coming up at all until I gave it some more rpms. I replaced the oil and fixed the leaks and now my lift works great.

Take the inspection cover off where your dipstick is and look in there with a flashlight. Do this with your mower on (pto disconnected) and see if you can see any oil leaks.

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Thanks Tim for the reply. when I turn the tractor off it takes about ten minutes for the brush hog to leak down.
Now as for what kind of fluid? I'm not sure as I had a tractor mechanic do it for me that works on 8 and 9N's exclusively. He was the one that told me it's normal for these 60-65 year old tractor to leak down a bit. He also he told me if it continues to leak down or lift slow (when hot) to try to use a heaver oil such as heavy duty 90 weight oil.
I'm not sure about all this and that's why I'm asking here. Most of the stuff on this lil' 8N I'm getting good at and she treats me very well but these hydraulic's I know nothing about.
Thanks again for all the help.
PS yes I know too that the pump too probably needs a complete rebuild but I'm just trying to get through growing season for now. Then she goes in for a complete pump overhaul. I'm guessing that to cost about 400 bones?

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