Tractor Repair: case/david brown 995 lift, david brown 995, head screws

Question
QUESTION: The lift will not work when the tractor is warm we replaced the seal's in the lift pump last year and it worked ok for a while but now back to not lifting when warm any ideas what the problem could be?

ANSWER: what seal did you replace as the hydraulic pump is in the back end you would have to split the tractor to do anything with the pump.if i had ripped it that far id put a new pump in.or do you mean you put seals in the lift piston

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QUESTION: it was a pump at the back end i dont know an awful lot about it i also should have said when you rise the lift leaver nothing happens until the leaver is nearly fully up then the lift goes up nearly fully and when you put the leaver down a bit the lift goes slowely down all the way you cant hold it in one place unless you lock it

Answer
well if you put a seal in there is a good chance it is gone again but something must be causeing it to go so inspect the shaft its on for wear and tightness
the lift probably needs to be adjusted and there could be some parts worn too you can make some adjustments just insided the plate underneat the hand brake lever held on by big philips head screws take this off and work the lift lever and you will see what you need to adjust