Increase 3pt lift capacity

[JaceCrane]

I have only owned compact tractors and have never had a reason to lift much with the 3pt system.
I might be getting into a business where a much bigger tractor is needed for 3pt weight capacity.
In my initial comparisons of brands and models I have noticed that a certain horsepower tractor category has a wide range of 3 point lift capacity’s. So here comes my question.

Can a larger gpm hydraulic pump be installed on a smaller tractor to give a large increase in lift capacity? Proposing putting a 40ish gpm pump on a 50-75 hp tractor.

Either way I believe I am headed into a new tractor, just trying to look at all my options. Thanks for your assistance and expertise.

 

[Agvg]

It's the pressure that creates lift, not volum.

 

[RNeumann]

As stated it’s pressure, not volume. In general the pumps can’t be changed for bigger ones. The spec differences probably has almost everything to do with where the manufacturers are lifting from on the arms.

If you are going into business that has a repeated task you don’t want a machine that will barely do that task. Unfortunately, for your wallet, it sounds like you are looking at a class of machine that is too small.

 

[jeff9366]

Hydraulic pump VOLUME determines potential work. Circuit RESTRICTIONS determine pressure.

 

[Tx Jim]

It's possible to raise 3 pt lift capacity by increasing relief valve opening pressure BUT IMHO manufactures set relief pressure for a reason

 

[ruffdog]

The size of the cylinder on the 3pt, available pressure from the pump, relief valve setting, geometry of 3pt linkage, and restrictions/leaks in the system play a role in how much it can lift.

 

[mikester]

I have only owned compact tractors and have never had a reason to lift much with the 3pt system.
I might be getting into a business where a much bigger tractor is needed for 3pt weight capacity.
In my initial comparisons of brands and models I have noticed that a certain horsepower tractor category has a wide range of 3 point lift capacity’s. So here comes my question.

Can a larger gpm hydraulic pump be installed on a smaller tractor to give a large increase in lift capacity? Proposing putting a 40ish gpm pump on a 50-75 hp tractor.

Either way I believe I am headed into a new tractor, just trying to look at all my options. Thanks for your assistance and expertise.

Not worth the effort, time or cost of trying to retrofit your tractor. Get a bigger tractor designed to handle your loads. Less aggravation and time lost repairing broken stuff.

 

[fried1765]

It's the pressure that creates lift, not volum.

I don't think so!
A 3" dia. cyl at 3000 psi can theoretically lift 21,000 lbs.
A 2" dia. cyl.at the same 3000 psi. can only lift 9,400 lbs.
The 3" cylinder with the same stroke length has 2.2 times the volume, at the SAME 3000 psi pressure.
Bigger diameter cylinders (more volume) lift heavier stuff,...... at the same pressure!

 

[ruffdog]

I don't think so!
A 3" dia. cyl at 3000 psi can theoretically lift 21,000 lbs.
A 2" dia. cyl.at the same 3000 psi. can only lift 9,400 lbs.
The 3" cylinder with the same stroke length has 2.2 times the volume, at the SAME 3000 psi pressure.
Bigger diameter cylinders (more volume) lift heavier stuff,...... at the same pressure!

The OP was talking about raising the pump volume (GPM) which would not in itself lift more weight. It is system (pump) pressure PSI x cylinder bore.

 

[ovrszd]

Hydraulic pump VOLUME determines potential work. Circuit RESTRICTIONS determine pressure.

Well stated Jeff. And often misunderstood.