Another Mitsu D3250 question - hydraulics this time

[Bartender]

Me again.
Same guy who knows the guy with the Mitsubishi D3250.

His 3-point system goes on vacation after running for about an hour. When the tractor's cold, the 3-point is very powerful and responsive. It doesn't think about it for a few seconds like my old Ford 600; it pulls those arms up right now.
However, after running for a while (the warmer the summer day the faster this occurs) the 3-point system will only drop, not raise. Let it sit for an hour and it works again.

He's running the standard weight oil for the tractor as recommended by Cowlitz Tractor, the Western Washington dealer who sold the machine. I assume trying heavier oil would be one trick, but seems to me we shouldn't have to.

Any thoughts on what usually causes this? I'm no hydraulics expert - only thing I can think of is tired relief valve.

 

[lens12]

Have you cleaned the pickup screen? Do that first. If it is clean we'll go on to the next possibilty.

 

[kennyd]

I would guess the hydraulic pump is putting out less pressure as it warms up.

But I am not famiiar with that machine at all...
Does it have a FEL?
Does it have power steering?
How old is this tractor?

 

[mit]

this is not expert advise here.from what u reported it is suggesting a component is failing when the tractor is hot(warm).it could be the control valve,the pump,the pressure relief valve.when it stop working (warm) you have to isolate to find the trouble.good luck