Why do CUT manufacturers not install larger hydraulic pumps?

[PILOON]

My MT180D was pathetically slow with the FEL so I added a crankshaft driven 2nd pump just 4 the FEL.
Lift is about 2x faster and I have plenty of power. The odd time with full load I do feel the slightest hesitation but nothing troublesome.
As a result I have 2 hydraulic reservoirs with the FEL 'post' serving as its own tank as it was designed to do.
The install was easy and straightforward, a bit of bracketry and a suitable U-joint with careful alignment.

 

[PILOON]

My MT180D was pathetically slow with the FEL so I added a crankshaft driven 2nd pump just 4 the FEL.
Lift is about 2x faster and I have plenty of power. The odd time with full load I do feel the slightest hesitation but nothing troublesome.
As a result I have 2 hydraulic reservoirs with the FEL 'post' serving as its own tank as it was designed to do.
The install was easy and straightforward, a bit of bracketry and a suitable U-joint with careful alignment.

 

[tlm720]

All this discussion has given me an idea. On the 4024T engine in my 4120 the serpentine belt runs over an idler pulley in a position that looks like it is meant for an accessory, probably the AC compressor on a cab tractor. Replace the idler with a clutch pump and plumb it in parallel with the tractor implement pump. One big enough to get 12 to 15 gpm total combined with the implement pump at 1800 engine rpm. Mount up a rocker switch in one of the currently unused spots in the right side operator panel and voilà, epump.

 

[IceStationZebra]

Using a belt drive isn't as simple as putting one on the PTO. You need to consider how much HP the belt can transfer. What size and number of ribs? Also need to consider the ratio of the crank pulley to the one on the pump. I've done HP calcs for V-belts before, would have to dig up serpentine belt info. ISZ

 

[TomSeller]

Using a belt drive isn't as simple as putting one on the PTO. You need to consider how much HP the belt can transfer. What size and number of ribs? Also need to consider the ratio of the crank pulley to the one on the pump. I've done HP calcs for V-belts before, would have to dig up serpentine belt info. ISZ

Also would have to worry about lining up the output pressures

 

[tlm720]

The pressure comes from the resistance, either the load or the relief valve. As long as the pump is capable of the max system pressure there is no problem. It would require a check valve on the clutch pump output to prevent the tractor pump from backflowing through the clutch pump when the clutch is disengaged. As far as Hp and ratios that is no problem either. I am an engineer and can figure all of that as needed. Probably the hardest part would be getting a decent size suction line plumbed to it as it would be on the opposite side of the engine as the current pump. Assuming it is feasible. I'm only talking about maybe 4 or 5 gpm at 2500 psi at 1800 engine rpms. That's about 8 hp with pump efficiency figured in. Probably only a little more than an AC compressor.

 

[art]

Having the options of playing with the trade-in units as well as the many makes of the new I've often found that tractors vary a lot on the hydraulic abilities. I've found smaller pump systems that can lift more then larger systems!!! Some even move faster then the larger pump units do to the size of cylinders and plumbing used.
I've found that some are faster, although capacity is sometimes lower, some the same, some that are smooth to the touch and some that are jerky. I've listened to customers talk of the differences of performance of the old vs the new tractors and what they enjoyed of either or disliked.
There are things that people often ask about the tractors capacity to do and some I don't recommend just do to overall economics!

 

[J_J]

You have to believe that the engineers kind of knew what they were doing in trying to put a tractor together.

You should also know that GPM's determine the speed of operation.

You should know that pressure determines the force applied or developed.

Then you have the mechanical aspect of the apparatus be it a loader , BH, or 3pt, or whatever.

Something large does not have to be the best you can do.

Something small and made better, may outwork the larger item.

When looking for a machine, you need some common sense as what do you want it to do.

Then test it out and see if it will do the job.

If you do your research well, you should come out with exactly what you want.

Buying something you don't know about is not smart at all.

You should use your knowledge as a bargaining chip.

A lot of times the salesman do not even know about the technical aspect of the machine and may give bad advise.

 

[jenkinsph]

After reading the entire thread I suggest you not be too concerned about the extra fuel burn at the higher rpms when using your log splitter. The additional fuel used to run the tractor at full speed vs. 1500 rpms is minor if the load is the same.

A better fix imo is a gas driven log splitter with a two stage pump if you have a lot of wood to split. For someone with a need for it the low pressure high flow first stage moves the ram quickly until it meets the resistance of the wood and then shifts to a smaller gear on the pump that produces a higher pressure with lower flow rating. The first stage may only develop about 600 psi before it hits the relief and the second stage can be much higher depending on the pump and cylinder ratings.

 

[the old grind]

A better fix imo is a gas driven log splitter with a two stage pump if you have a lot of wood to split.

I've always felt that way about PTO generators too, esp if demand is < say 10kw or so. Tornado goes by and spares house & barn. Fallen trees block driveway and tractor is tied up keeping refrig & central air going 24hrs/day.

I think of a tractor as a way to haul wood to the splitter vs the opposite. Got two tractors? Only a prob if one needs the higher-flow-hydraulics of the 'bigger' one to process promptly. btw: Can't imagine a splitter without a 2-stage pump and the word 'efficiency' being mentioned in the same sentence, having seen what they'll do.